Search Results

Search found 18523 results on 741 pages for 'multipart form'.

Page 447/741 | < Previous Page | 443 444 445 446 447 448 449 450 451 452 453 454  | Next Page >

  • SQL Azure Reporting Limited CTP Arrived

    - by Shaun
    It’s about 3 months later when I registered the SQL Azure Reporting CTP on the Microsoft Connect after TechED 2010 China. Today when I checked my mailbox I found that the SQL Azure team had just accepted my request and sent the activation code over to me. So let’s have a look on the new SQL Azure Reporting.   Concept The SQL Azure Reporting provides cloud-based reporting as a service, built on SQL Server Reporting Services and SQL Azure technologies. Cloud-based reporting solutions such as SQL Azure Reporting provide many benefits, including rapid provisioning, cost-effective scalability, high availability, and reduced management overhead for report servers; and secure access, viewing, and management of reports. By using the SQL Azure Reporting service, we can do: Embed the Visual Studio Report Viewer ADO.NET Ajax control or Windows Form control to view the reports deployed on SQL Azure Reporting Service in our web or desktop application. Leverage the SQL Azure Reporting SOAP API to manage and retrieve the report content from any kinds of application. Use the SQL Azure Reporting Service Portal to navigate and view the reports deployed on the cloud. Since the SQL Azure Reporting was built based on the SQL Server 2008 R2 Reporting Service, we can use any tools we are familiar with, such as the SQL Server Integration Studio, Visual Studio Report Viewer. The SQL Azure Reporting Service runs as a remote SQL Server Reporting Service just on the cloud rather than on a server besides us.   Establish a New SQL Azure Reporting Let’s move to the windows azure deveploer portal and click the Reporting item from the left side navigation bar. If you don’t have the activation code you can click the Sign Up button to send a requirement to the Microsoft Connect. Since I already recieved the received code mail I clicked the Provision button. Then after agree the terms of the service I will select the subscription for where my SQL Azure Reporting CTP should be provisioned. In this case I selected my free Windows Azure Pass subscription. Then the final step, paste the activation code and enter the password of our SQL Azure Reporting Service. The user name of the SQL Azure Reporting will be generated by SQL Azure automatically. After a while the new SQL Azure Reporting Server will be shown on our developer portal. The Reporting Service URL and the user name will be shown as well. We can reset the password from the toolbar button.   Deploy Report to SQL Azure Reporting If you are familiar with SQL Server Reporting Service you will find this part will be very similar with what you know and what you did before. Firstly we open the SQL Server Business Intelligence Development Studio and create a new Report Server Project. Then we will create a shared data source where the report data will be retrieved from. This data source can be SQL Azure but we can use local SQL Server or other database if it opens the port up. In this case we use a SQL Azure database located in the same data center of our reporting service. In the Credentials tab page we entered the user name and password to this SQL Azure database. The SQL Azure Reporting CTP only available at the North US Data Center now so that the related SQL Server and hosted service might be better to select the same data center to avoid the external data transfer fee. Then we create a very simple report, just retrieve all records from a table named Members and have a table in the report to list them. In the data source selection step we choose the shared data source we created before, then enter the T-SQL to select all records from the Member table, then put all fields into the table columns. The report will be like this as following In order to deploy the report onto the SQL Azure Reporting Service we need to update the project property. Right click the project node from the solution explorer and select the property item. In the Target Server URL item we will specify the reporting server URL of our SQL Azure Reporting. We can go back to the developer portal and select the reporting node from the left side, then copy the Web Service URL and paste here. But notice that we need to append “/reportserver” after pasted. Then just click the Deploy menu item in the context menu of the project, the Visual Studio will compile the report and then upload to the reporting service accordingly. In this step we will be prompted to input the user name and password of our SQL Azure Reporting Service. We can get the user name from the developer portal, just next to the Web Service URL in the SQL Azure Reporting page. And the password is the one we specified when created the reporting service. After about one minute the report will be deployed succeed.   View the Report in Browser SQL Azure Reporting allows us to view the reports which deployed on the cloud from a standard browser. We copied the Web Service URL from the reporting service main page and appended “/reportserver” in HTTPS protocol then we will have the SQL Azure Reporting Service login page. After entered the user name and password of the SQL Azure Reporting Service we can see the directories and reports listed. Click the report will launch the Report Viewer to render the report.   View Report in a Web Role with the Report Viewer The ASP.NET and Windows Form Report Viewer works well with the SQL Azure Reporting Service as well. We can create a ASP.NET Web Role and added the Report Viewer control in the default page. What we need to change to the report viewer are Change the Processing Mode to Remote. Specify the Report Server URL under the Server Remote category to the URL of the SQL Azure Reporting Web Service URL with “/reportserver” appended. Specify the Report Path to the report which we want to display. The report name should NOT include the extension name. For example my report was in the SqlAzureReportingTest project and named MemberList.rdl then the report path should be /SqlAzureReportingTest/MemberList. And the next one is to specify the SQL Azure Reporting Credentials. We can use the following class to wrap the report server credential. 1: private class ReportServerCredentials : IReportServerCredentials 2: { 3: private string _userName; 4: private string _password; 5: private string _domain; 6:  7: public ReportServerCredentials(string userName, string password, string domain) 8: { 9: _userName = userName; 10: _password = password; 11: _domain = domain; 12: } 13:  14: public WindowsIdentity ImpersonationUser 15: { 16: get 17: { 18: return null; 19: } 20: } 21:  22: public ICredentials NetworkCredentials 23: { 24: get 25: { 26: return null; 27: } 28: } 29:  30: public bool GetFormsCredentials(out Cookie authCookie, out string user, out string password, out string authority) 31: { 32: authCookie = null; 33: user = _userName; 34: password = _password; 35: authority = _domain; 36: return true; 37: } 38: } And then in the Page_Load method, pass it to the report viewer. 1: protected void Page_Load(object sender, EventArgs e) 2: { 3: ReportViewer1.ServerReport.ReportServerCredentials = new ReportServerCredentials( 4: "<user name>", 5: "<password>", 6: "<sql azure reporting web service url>"); 7: } Finally deploy it to Windows Azure and enjoy the report.   Summary In this post I introduced the SQL Azure Reporting CTP which had just available. Likes other features in Windows Azure, the SQL Azure Reporting is very similar with the SQL Server Reporting. As you can see in this post we can use the existing and familiar tools to build and deploy the reports and display them on a website. But the SQL Azure Reporting is just in the CTP stage which means It is free. There’s no support for it. Only available at the North US Data Center. You can get more information about the SQL Azure Reporting CTP from the links following SQL Azure Reporting Limited CTP at MSDN SQL Azure Reporting Samples at TechNet Wiki You can download the solutions and the projects used in this post here.   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

    Read the article

  • Who IS Brian Solis?

    - by Michael Snow
    Q: Brian, Welcome to the WebCenter Blog. Can you tell our readers your current role and what career path brought you here? A: I’m proudly serving as a principal analyst at Altimeter Group, a research based advisory firm in Silicon Valley. My career path, well, let’s just say it’s a long and winding road. As a kid, I was fascinated with technology. I learned programming at an early age and found myself naturally drawn to all things tech. I started my career as a database programmer at a technology marketing agency in Southern California. When I saw the chance to work with tech companies and help them better market their capabilities to businesses and consumers, I switched focus from programming to marketing and advertising. As technologist, my approach to marketing was different. I didn’t believe in hype, fluff or buzz words. I believed in translating features into benefits and specifications and capabilities into solutions for real world problems and opportunities. In the mid 90’s I experimented with direct to consumer/customer engagement in dedicated technology forums and boards. I quickly realized that the entire approach to do so would need to change. Therefore, I learned and developed new methods for a more social and informed way of engaging people in ways that helped them, marketed the company, and also tied to tangible benefits for the company. This work would lead me to start an agency in 1999 dedicated to interactive marketing. As I continued to experiment with interactive platforms, I developed interesting methods for converting one-to-many forms of media into one-to-one-to-many programs. I ran that company until joining Altimeter Group. Along the way, in the early 2000s, I realized that everything was changing and that there were others like me finding success in what would become a more social form of media. I dedicated a significant amount of my time to sharing everything that I learned in the form of articles, blogs, and eventually books. My mission became to share my experience with anyone who’d listen. It would later become much bigger than marketing, this would lead to a decade of work, that still continues, in business transformation. Then and now, I find myself always assuming the role of a student. Q: As an industry analyst & technology change evangelist, what are you primarily focused on these days? A: As a digital analyst, I study how disruptive technology impacts business. As an aspiring social scientist, I study how technology affects human behavior. I explore both horizons professionally and personally to better understand the future of popular culture and also the opportunities that exist for organizations to improve relationships and experiences with customers and the people that are important to them. Q: People cite that the line between work and life is getting more and more blurred. Do you see your personal life influencing your professional work? A: The line between work and life isn’t blurred it’s been overtly crossed and erased. We live in an always on society. The digital lifestyle keeps us connected to one another it keeps us connected all the time. Whether your sending or checking email, trying to catch up, or simply trying to get ahead, people are spending the equivalent of an extra day at work in the time they spend out of work…working. That’s absurd. It’s a matter of survival. It’s also a matter of unintended, subconscious self-causation. We brought this on ourselves and continue to do so. Think about your day. You’re in meetings for the better part of each day. You probably spend evenings and weekends catching up on email and actually doing the work you couldn’t get to during the day. And, your co-workers and executives are doing the same thing. So if you try to slow down, you find yourself at a disadvantage as you’re willfully pulling yourself out of an unfortunate culture of whenever wherever business dynamics. If you’re unresponsive or unreachable, someone within your organization or on your team is accessible. Over time, this could contribute to unfavorable impressions. I choose to steer my life balance in ways that complement one another. But, I don’t pretend to have this figured out by any means. In fact, I find myself swimming upstream like those around me. It’s essentially a competition for relevance and at some point I’ll learn how to earn attention and relevance while redrawing the line between work and life. Q: How can people keep up with what you’re working on? A: The easy answer is that people can keep up with me at briansolis.com. But, I also try to reach people where their attention is focused. Whether it’s Facebook (facebook.com/briansolis), Twitter (@briansolis), Google+ (+briansolis), Youtube (briansolis.tv) or through books and conferences, people can usually find me in a place of their choosing. Q: Recently, you’ve been working with us here at Oracle on something exciting coming up later this week. What’s on the horizon? A: I spent some time with the Oracle team reviewing the idea of Digital Darwinism and how technology and society are evolving faster than many organizations can adapt. Digital Darwinism: How Brands Can Survive the Rapid Evolution of Society and Technology Thursday, December 13, 2012, 10 a.m. PT / 1 p.m. ET Q: You’ve been very actively pursued for media interviews and conference and company speaking engagements – anything you’d like to share to give us a sneak peak of what to expect on Thursday’s webcast? A: We’re inviting guests to join us online as we dive into the future of business and how the convergence of technology and connected consumerism would ultimately impact how business is done. It’ll be an exciting and revealing conversation that explores just how much everything is changing. We’ll also review the importance of adapting to emergent trends and how to compete for the future. It’s important to recognize that change is not happening to us, it’s happening because of us. We are part of the revolution and therefore we need to help organizations adapt from the inside out. Watch the Entire Oracle Social Business Thought Leaders Webcast Series On-Demand and Stay Tuned for More to Come in 2013!

    Read the article

  • CodePlex Daily Summary for Monday, March 22, 2010

    CodePlex Daily Summary for Monday, March 22, 2010New Projects[Tool] Vczh Non-public DLL Classes Caller: Generate C# code for you to call non-public classes in DLLs very easily.Artefact Animator: Artefact Animator provides an easy to use framework for procedural time-based animations in Silverlight and WPF.cacheroo: Cacheroo is a social networking community that will make it easier for people who love geocaching to get connected.Data Processing Toolkit: An utility app to collected data from different sources (i.e. bugzilla bug reports) in a structured way. We are currently setting up the site. Mo...eXternal SQL Bridge (PHP): The eXternal SQL Bridge (XSB) allows you to bridge two websites together in a secure manner through pre-shared keys. XSB is resilient against repla...'G' - Language to Define Gestures for Touch Based Applications: A cross plat form multi-touch application framework with a language to define gestures. The application is build on Silverlight 4.0 and the languag...IIS Network Diagnostic Tools: Web implementation of "looking glass" like services (ping, traceroute) as HTTP modules for Internet Information Services.Interop Router: This project establishes a communication framework and job dispatcher for a mixed operating system cluster environment.L2 Commander: L2Commander makes it easier for both new and old l2j users to manage your server.You no longer have to waste time on finding the files you need and...MediaHelper: A utility to help clean up empty/unwanted files and folders in your filesystem.mhinze: matt hinze stuffOneMan: Focus on Silverlight and WCF technology.Rss Photo Frame Android Widget: RSS Photo Frame Android Widget permits showing pictures from any RSS feed on your Android device's desktopSingle Web Session: Web Tool Kits Current project provide developer with different tools that help to enhance web site performance, security, and other common functio...Work Item Visualization: Use DGML to visualize and analyze your TFS Work Items. Included is the ability to perform basic risk/impact analysis. It helps answer the question,...New Releases[Tool] Vczh Non-public DLL Classes Caller: Wrapper Coder (beta): Click "<Click Me To Open Assembly File>", WrapperCoder will load the assembly and referenced assembly. Check the non-public classes that you want...APS - Automatic Print Screen: APS 1.0: APS automatizes the tasks of paste the image in Paint and save it after print screen or alt+print screen. Choose directory, name and file extension...BTP Tools: e-Sword generator build 20100321: 1. Modify the indent after subtitle. 2. Add 2 spaces after subtitle.Combres - WebForm & MVC Client-side Resource Combine Library: Combres 2.0: Changes since last version (1.2) Support ignore Combres pipeline in debug mode - see issue #6088 Debug mode generates comment helping identify in...Desafio Office 2010 Brasil: DesafioOutlook: Controlando um robo com o Outlook 2010dylan.NET: dylan.NET v. 9.4: Adding Platform Invocation Services Support, full Managed Pointer Support, Charset,Dllimport,Callconv setting for P/Invoke, MarshalAs for parametersFamily Tree Analyzer: Version 1.3.2.0: Version 1.3.2.0 Add open folder button to IGI Search Form Fixes to Fact Location processing - IGIName renamed to RegionID Fix if Region ID not fou...Fasterflect - A Fast and Simple Reflection API: Fasterflect 2.0: We are pleased to release version 2.0 of Fasterflect, which contains a lot of additions and improvements from the previous version. Please refer t...IIS Network Diagnostic Tools: 1.0: Initial public release.Informant: Informant (Desktop) v0.1: This release allows users to send sms messages to 1-Many Groups or 1-Many contacts. It is a very basic release of the application. No styling has b...InfoService: InfoService v1.5 - MPE1 Package: InfoService Release v1.5.0.65 Please read Plugin installation for installation instructions.InfoService: InfoService v1.5 - RAR Package: InfoService Release v1.5.0.65 Please read Plugin installation for installation instructions.L2 Commander: Source Code Link: Where to find our source.ModularCMS: ModularCMS 1.2: Minor bug fixes.NMTools: NMTools-v40b0-20100321-0: The most noticeable aspect of this release is that NMTools is now an independent project. It will no longer tied to OpenSLIM. Nevertheless, OpenSLI...SharePoint LogViewer: SharePoint LogViewer 1.5.3: Log loading performance enhanced. Search text box now has auto complete feature.Single Web Session: Single Web Session: !Single Web Session! <httpModules> <add name="SingleSession" type="SingleWebSession.Model.WebSessionModule, SingleWebSession"/> </httpModules>Sprite Sheet Packer: 2.1 Release: Made a few crucial fixes from 2.0: - Fixed error with paths having spaces. - Fixed error with UI not unlocking. - Fixed NullReferenceException on ...uManage - AD Self-Service Portal: uManage v1.1 (.NET 4.0 RC): Updated Releasev1.1 Adds the primary ability to setup and configure the application through a setup wizard. The setup wizard will continue to evol...VCC: Latest build, v2.1.30321.0: Automatic drop of latest buildVS ChessMania: VS ChessMania V2 March Beta: Second Beta Release with move correction and making application more safe for user. New features will be added soon.WatchersNET CKEditor™ Provider for DotNetNuke: CKEditor Provider 1.9.00: Whats New Added New Toolbar Plugin (By Kent Safransk) 'MediaEmbed' to Include Embed Media from Youtube, Vimeo, etc. Media Embed Plugin Added New ...WeatherBar: WeatherBar 1.0 [No Installation]: Extract the ZIP archive and run WeatherBar.exe. Current release contains some bugs that will be fixed in the next version. Check the Issue Tracker...Work Item Visualization: Release 1.0: This is the initial release of the Work Item Visualization tool. There are no known issues when it comes to the visualization aspects of the tool b...WPF Application Framework (WAF): WPF Application Framework (WAF) 1.0.0.10: Version: 1.0.0.10 (Milestone 10): This release contains the source code of the WPF Application Framework (WAF) and the sample applications. Requi...WPF AutoComplete TextBox Control: Version 1.2: What's Newadds AutoAppend feature adds a new provider: UrlHistoryDataProvider sample application is updated to reflect the new things Bug Fixe...ZoomBarPlus: V2 (Beta): - Fixed bug: if the active window changed while you were in the middle of a single tap delay, long tap delay, or swipe-repeat, it would continue re...Most Popular ProjectsMetaSharpSavvy DateTimeRawrWBFS ManagerSilverlight ToolkitASP.NET Ajax LibraryMicrosoft SQL Server Product Samples: DatabaseAJAX Control ToolkitLiveUpload to FacebookWindows Presentation Foundation (WPF)Most Active ProjectsLINQ to TwitterRawrOData SDK for PHPjQuery Library for SharePoint Web ServicesDirectQPHPExcelFarseer Physics Enginepatterns & practices – Enterprise LibraryBlogEngine.NETNB_Store - Free DotNetNuke Ecommerce Catalog Module

    Read the article

  • Adaptive ADF/WebCenter template for the iPad

    - by Maiko Rocha
    One of my WebCenter Portal customers was asking about adaptive design with ADF/WebCenter Portal and how they could go about creating an adaptive iPad template for their WebCenter Portal application. They were looking not only for the out-of-the-box support for mobile Safari which is certified against PS5+ (11.1.1.6) for ADF/WebCenter - but also to create a specific template to streamline their workflow on the iPad. Seems like they wanted something in the lines of Yahoo! Mail provides for the iPad - so the example I will use is shamelessly inspired by Y! Mail's iPad UI.  But first, let's quickly understand how can we bake in some adaptive goodness into ADF Faces. First thing we need to understand is, yes, there are a couple of constraints that we will need to work around, namely, the use or layout managers and skins. Please also keep in mind that I'm not and I don't pretend to be a web designer, much less an UX specialist, so feel free to leave your thoughts on the matter in the comments section. Now, back to the limitations. Layout Managers ADF Faces layout managers create an abstraction on top of the generated HTML code for a page so a developer doesn't need to be worried about how to size and dimension the UI layout (eg, af:panelStretchLayout). Although layout managers are very helpful, in this specific situation we will need to know a little bit more of how the final HTML is being rendered so we can apply the CSS class accordingly and create transition containers where the media queries will be applied - now, if you're using 11gR2 (11.1.2.2.3) there's the new component af:panelGridLayout (here and here) that will greatly improve creating responsive templates and pages because it is based on the grid/fluid systems and will generate straight out to DIVs on your final page. For now, I'm limited to PS5 and the af:panelStretchLayout component as a starting point because that's the release my customer is on. Skins You won't be able to use media queries, or use anything with "@" notation on the skin CSS file - the skin pre-processor will remove all extraneous "@" from the CSS file. The solution is to split your CSS in two separate files: a skin CSS file and plain CSS where you will add the media queries. The issue here is that you won't be able to use media queries for any faces components. We can, though, still apply the media queries for the components like af:panelGroupLayout and af:panelBorderLayout through their styleClass property to enable these components to be responsive to to the iPad orientation, by changing its dimensions, font sizes, hide/show areas, etc. Difference between responsive and adaptive design The best definition of adaptive vs responsive web design I could find is this: “Responsive web design,” as coined by Ethan Marcotte, means “fluid grids, fluid images/media & media queries.” “Adaptive web design,” as I use it, is about creating interfaces that adapt to the user’s capabilities (in terms of both form and function). To me, “adaptive web design” is just another term for “progressive enhancement” of which responsive web design can (an often should) be an integral part, but is a more holistic approach to web design in that it also takes into account varying levels of markup, CSS, JavaScript and assistive technology support. Responsive/adapative web design is much more than slapping an HTML template with CSS around your content or application. The content and application themselves are part of your web design - in other words, a responsive template is just an afterthought if it is not originating from a responsive design the involves the whole web application/s. Tips on responsive / adapative design with ADF/WebCenter Some of the tips listed below were already mentioned in multiple blog posts about ADF layout and skinning, but it is still worth remembering: a simple guideline for ADF/WebCenter apps would be to first create a high-level group of devices, for example: smartphones, tablets,  and desktop. For each of these large groups, create the basic structure to provide responsiveness: a page template, a skin, and an external CSS: pagetemplate_smartphone.jspx, smartphone_skin.css, smartphone-responsive.css pagetemplate_tablet.jspx, tablet_skin.css, tablet-responsive.css pagetemplate_desktop.jspx, desktop_skin.css, desktop-responsive.css These three assets can be changed on the fly through an user-agent check on the server side, delivering the right UI to the right device. Within each of the assets, you can make fine adjustments for each subgroup of devices with media queries - for example, smart phones with different screen dimensions and pixel density. Having these three groups and the corresponding assets per group seem to be a good compromise between trying to put everything on a single set of assets - specially considering the constraints above - and going to the other side of the spectrum to create assets per discrete device (iPhone4, iPhone5, Nexus, S3, etc.). Keep in mind that these are my rules and are not in any shape or form a best practice - this is how it fits best for the scenarios I've been working with. If you need to use HTML tags on your page, surround them with af:group to protect the DOM structure For stretchable/fluid layouts: Use non-stretching containers: panelGroupLayout, panelBorderLayout, … panelBorderLayout can be used to approximate HTML table component To avoid multiple scroll bars, do not nest scrolling PanelGroupLayout components. Consider layout="vertical" For stretchable/fluid layouts: Most stretchable ADF components also work in flowing context with dimensionsFrom="auto" To stretch a component horizontally, use styleClass="AFStretchWidth" instead of  "width:100%" Skinning Don't use CSS3 @media, @import, animations, etc. on skin css files. They will be removed. CSS3 properties within a class (box-shadow, transition, etc.) work just fine. Consider resetting some skin classes to better control their rendering: body {color: inherit;font: inherit;} af|document {-tr-inhibit: all;} af|commandLink {-tr-inhibit: all;} af|goLink {-tr-inhibit: all;} af|inputText::content {font: inherit;} Specific meta tags and CSS properties: Use  <meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0"/> to avoid zooming (if you want) Use -webkit-overflow-scrolling: touch to enable native momentum scrolling within overflown areas (here) Use text-rendering: optmizeLegibility to improve readability. (here) User text-overflow: ellipsis to gracefully crop overflown text. (here) The meta-tags are included in each and every page in the metaContainer facet of af:document tag. You can also use a javascript to inject the meta-tags from the template. For the purpose of the example, I wanted to use as few workarounds as possible.   The iPad template and sample application This sample application has been built as a WebCenter Portal application, but you will also be able to reuse the template and techniques on your vanilla ADF application. Keep in mind that I'm neither a designer nor a CSS specialist, so please don't bash me too much on the messy CSS file you'll find on the application.  I've extended the provided PreferencesBean class that comes with WebCenter Portal and added code to dinamically change the template and skin on the fly.   This is the sample application in landscape orientation: This is the sample application in portrait orientation - the left side menu hides automatically based on a CSS media query: Another screenshot with a skinned popup opened: This is a sample application for you to play with - ideally you shouldn't use it as a starting point. On the left side bar you will find links rendered from a WebCenter Portal navigation model - the link triggers a full request through an af:goLink, while the light blue PPR button triggers a PPR navigation. The dark blue toolbar buttons at the top don't have any function,while the Approve and Reject buttons show a skinned popup. The search box of course doesn't have any behavior attahed to it either. There's a known issue right now with some PPR calls that are randomly generating a 403 error redirecting to the login page - I didn't have time to investigate if this is iOS6 specific or not - if you have any insights please let me know your findings. You can download the sample here.

    Read the article

  • WebSocket and Java EE 7 - Getting Ready for JSR 356 (TOTD #181)

    - by arungupta
    WebSocket is developed as part of HTML 5 specification and provides a bi-directional, full-duplex communication channel over a single TCP socket. It provides dramatic improvement over the traditional approaches of Polling, Long-Polling, and Streaming for two-way communication. There is no latency from establishing new TCP connections for each HTTP message. There is a WebSocket API and the WebSocket Protocol. The Protocol defines "handshake" and "framing". The handshake defines how a normal HTTP connection can be upgraded to a WebSocket connection. The framing defines wire format of the message. The design philosophy is to keep the framing minimum to avoid the overhead. Both text and binary data can be sent using the API. WebSocket may look like a competing technology to Server-Sent Events (SSE), but they are not. Here are the key differences: WebSocket can send and receive data from a client. A typical example of WebSocket is a two-player game or a chat application. Server-Sent Events can only push data data to the client. A typical example of SSE is stock ticker or news feed. With SSE, XMLHttpRequest can be used to send data to the server. For server-only updates, WebSockets has an extra overhead and programming can be unecessarily complex. SSE provides a simple and easy-to-use model that is much better suited. SSEs are sent over traditional HTTP and so no modification is required on the server-side. WebSocket require servers that understand the protocol. SSE have several features that are missing from WebSocket such as automatic reconnection, event IDs, and the ability to send arbitrary events. The client automatically tries to reconnect if the connection is closed. The default wait before trying to reconnect is 3 seconds and can be configured by including "retry: XXXX\n" header where XXXX is the milliseconds to wait before trying to reconnect. Event stream can include a unique event identifier. This allows the server to determine which events need to be fired to each client in case the connection is dropped in between. The data can span multiple lines and can be of any text format as long as EventSource message handler can process it. WebSockets provide true real-time updates, SSE can be configured to provide close to real-time by setting appropriate timeouts. OK, so all excited about WebSocket ? Want to convert your POJOs into WebSockets endpoint ? websocket-sdk and GlassFish 4.0 is here to help! The complete source code shown in this project can be downloaded here. On the server-side, the WebSocket SDK converts a POJO into a WebSocket endpoint using simple annotations. Here is how a WebSocket endpoint will look like: @WebSocket(path="/echo")public class EchoBean { @WebSocketMessage public String echo(String message) { return message + " (from your server)"; }} In this code "@WebSocket" is a class-level annotation that declares a POJO to accept WebSocket messages. The path at which the messages are accepted is specified in this annotation. "@WebSocketMessage" indicates the Java method that is invoked when the endpoint receives a message. This method implementation echoes the received message concatenated with an additional string. The client-side HTML page looks like <div style="text-align: center;"> <form action=""> <input onclick="send_echo()" value="Press me" type="button"> <input id="textID" name="message" value="Hello WebSocket!" type="text"><br> </form></div><div id="output"></div> WebSocket allows a full-duplex communication. So the client, a browser in this case, can send a message to a server, a WebSocket endpoint in this case. And the server can send a message to the client at the same time. This is unlike HTTP which follows a "request" followed by a "response". In this code, the "send_echo" method in the JavaScript is invoked on the button click. There is also a <div> placeholder to display the response from the WebSocket endpoint. The JavaScript looks like: <script language="javascript" type="text/javascript"> var wsUri = "ws://localhost:8080/websockets/echo"; var websocket = new WebSocket(wsUri); websocket.onopen = function(evt) { onOpen(evt) }; websocket.onmessage = function(evt) { onMessage(evt) }; websocket.onerror = function(evt) { onError(evt) }; function init() { output = document.getElementById("output"); } function send_echo() { websocket.send(textID.value); writeToScreen("SENT: " + textID.value); } function onOpen(evt) { writeToScreen("CONNECTED"); } function onMessage(evt) { writeToScreen("RECEIVED: " + evt.data); } function onError(evt) { writeToScreen('<span style="color: red;">ERROR:</span> ' + evt.data); } function writeToScreen(message) { var pre = document.createElement("p"); pre.style.wordWrap = "break-word"; pre.innerHTML = message; output.appendChild(pre); } window.addEventListener("load", init, false);</script> In this code The URI to connect to on the server side is of the format ws://<HOST>:<PORT>/websockets/<PATH> "ws" is a new URI scheme introduced by the WebSocket protocol. <PATH> is the path on the endpoint where the WebSocket messages are accepted. In our case, it is ws://localhost:8080/websockets/echo WEBSOCKET_SDK-1 will ensure that context root is included in the URI as well. WebSocket is created as a global object so that the connection is created only once. This object establishes a connection with the given host, port and the path at which the endpoint is listening. The WebSocket API defines several callbacks that can be registered on specific events. The "onopen", "onmessage", and "onerror" callbacks are registered in this case. The callbacks print a message on the browser indicating which one is called and additionally also prints the data sent/received. On the button click, the WebSocket object is used to transmit text data to the endpoint. Binary data can be sent as one blob or using buffering. The HTTP request headers sent for the WebSocket call are: GET ws://localhost:8080/websockets/echo HTTP/1.1Origin: http://localhost:8080Connection: UpgradeSec-WebSocket-Extensions: x-webkit-deflate-frameHost: localhost:8080Sec-WebSocket-Key: mDbnYkAUi0b5Rnal9/cMvQ==Upgrade: websocketSec-WebSocket-Version: 13 And the response headers received are Connection:UpgradeSec-WebSocket-Accept:q4nmgFl/lEtU2ocyKZ64dtQvx10=Upgrade:websocket(Challenge Response):00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00 The headers are shown in Chrome as shown below: The complete source code shown in this project can be downloaded here. The builds from websocket-sdk are integrated in GlassFish 4.0 builds. Would you like to live on the bleeding edge ? Then follow the instructions below to check out the workspace and install the latest SDK: Check out the source code svn checkout https://svn.java.net/svn/websocket-sdk~source-code-repository Build and install the trunk in your local repository as: mvn install Copy "./bundles/websocket-osgi/target/websocket-osgi-0.3-SNAPSHOT.jar" to "glassfish3/glassfish/modules/websocket-osgi.jar" in your GlassFish 4 latest promoted build. Notice, you need to overwrite the JAR file. Anybody interested in building a cool application using WebSocket and get it running on GlassFish ? :-) This work will also feed into JSR 356 - Java API for WebSocket. On a lighter side, there seems to be less agreement on the name. Here are some of the options that are prevalent: WebSocket (W3C API, the URL is www.w3.org/TR/websockets though) Web Socket (HTML5 Demos - html5demos.com/web-socket) Websocket (Jenkins Plugin - wiki.jenkins-ci.org/display/JENKINS/Websocket%2BPlugin) WebSockets (Used by Mozilla - developer.mozilla.org/en/WebSockets, but use WebSocket as well) Web sockets (HTML5 Working Group - www.whatwg.org/specs/web-apps/current-work/multipage/network.html) Web Sockets (Chrome Blog - blog.chromium.org/2009/12/web-sockets-now-available-in-google.html) I prefer "WebSocket" as that seems to be most common usage and used by the W3C API as well. What do you use ?

    Read the article

  • Refreshing Your PC Won’t Help: Why Bloatware is Still a Problem on Windows 8

    - by Chris Hoffman
    Bloatware is still a big problem on new Windows 8 and 8.1 PCs. Some websites will tell you that you can easily get rid of manufacturer-installed bloatware with Windows 8′s Reset feature, but they’re generally wrong. This junk software often turns the process of powering on your new PC from what could be a delightful experience into a tedious slog, forcing you to spend hours cleaning up your new PC before you can enjoy it. Why Refreshing Your PC (Probably) Won’t Help Manufacturers install software along with Windows on their new PCs. In addition to hardware drivers that allow the PC’s hardware to work properly, they install more questionable things like trial antivirus software and other nagware. Much of this software runs at boot, cluttering the system tray and slowing down boot times, often dramatically. Software companies pay computer manufacturers to include this stuff. It’s installed to make the PC manufacturer money at the cost of making the Windows computer worse for actual users. Windows 8 includes “Refresh Your PC” and “Reset Your PC” features that allow Windows users to quickly get their computers back to a fresh state. It’s essentially a quick, streamlined way of reinstalling Windows.  If you install Windows 8 or 8.1 yourself, the Refresh operation will give your PC a clean Windows system without any additional third-party software. However, Microsoft allows computer manufacturers to customize their Refresh images. In other words, most computer manufacturers will build their drivers, bloatware, and other system customizations into the Refresh image. When you Refresh your computer, you’ll just get back to the factory-provided system complete with bloatware. It’s possible that some computer manufacturers aren’t building bloatware into their refresh images in this way. It’s also possible that, when Windows 8 came out, some computer manufacturer didn’t realize they could do this and that refreshing a new PC would strip the bloatware. However, on most Windows 8 and 8.1 PCs, you’ll probably see bloatware come back when you refresh your PC. It’s easy to understand how PC manufacturers do this. You can create your own Refresh images on Windows 8 and 8.1 with just a simple command, replacing Microsoft’s image with a customized one. Manufacturers can install their own refresh images in the same way. Microsoft doesn’t lock down the Refresh feature. Desktop Bloatware is Still Around, Even on Tablets! Not only is typical Windows desktop bloatware not gone, it has tagged along with Windows as it moves to new form factors. Every Windows tablet currently on the market — aside from Microsoft’s own Surface and Surface 2 tablets — runs on a standard Intel x86 chip. This means that every Windows 8 and 8.1 tablet you see in stores has a full desktop with the capability to run desktop software. Even if that tablet doesn’t come with a keyboard, it’s likely that the manufacturer has preinstalled bloatware on the tablet’s desktop. Yes, that means that your Windows tablet will be slower to boot and have less memory because junk and nagging software will be on its desktop and in its system tray. Microsoft considers tablets to be PCs, and PC manufacturers love installing their bloatware. If you pick up a Windows tablet, don’t be surprised if you have to deal with desktop bloatware on it. Microsoft Surfaces and Signature PCs Microsoft is now selling their own Surface PCs that they built themselves — they’re now a “devices and services” company after all, not a software company. One of the nice things about Microsoft’s Surface PCs is that they’re free of the typical bloatware. Microsoft won’t take money from Norton to include nagging software that worsens the experience. If you pick up a Surface device that provides Windows 8.1 and 8 as Microsoft intended it — or install a fresh Windows 8.1 or 8 system — you won’t see any bloatware. Microsoft is also continuing their Signature program. New PCs purchased from Microsoft’s official stores are considered “Signature PCs” and don’t have the typical bloatware. For example, the same laptop could be full of bloatware in a traditional computer store and clean, without the nasty bloatware when purchased from a Microsoft Store. Microsoft will also continue to charge you $99 if you want them to remove your computer’s bloatware for you — that’s the more questionable part of the Signature program. Windows 8 App Bloatware is an Improvement There’s a new type of bloatware on new Windows 8 systems, which is thankfully less harmful. This is bloatware in the form of included “Windows 8-style”, “Store-style”, or “Modern” apps in the new, tiled interface. For example, Amazon may pay a computer manufacturer to include the Amazon Kindle app from the Windows Store. (The manufacturer may also just receive a cut of book sales for including it. We’re not sure how the revenue sharing works — but it’s clear PC manufacturers are getting money from Amazon.) The manufacturer will then install the Amazon Kindle app from the Windows Store by default. This included software is technically some amount of clutter, but it doesn’t cause the problems older types of bloatware does. It won’t automatically load and delay your computer’s startup process, clutter your system tray, or take up memory while you’re using your computer. For this reason, a shift to including new-style apps as bloatware is a definite improvement over older styles of bloatware. Unfortunately, this type of bloatware has not replaced traditional desktop bloatware, and new Windows PCs will generally have both. Windows RT is Immune to Typical Bloatware, But… Microsoft’s Windows RT can’t run Microsoft desktop software, so it’s immune to traditional bloatware. Just as you can’t install your own desktop programs on it, the Windows RT device’s manufacturer can’t install their own desktop bloatware. While Windows RT could be an antidote to bloatware, this advantage comes at the cost of being able to install any type of desktop software at all. Windows RT has also seemingly failed — while a variety of manufacturers came out with their own Windows RT devices when Windows 8 was first released, they’ve all since been withdrawn from the market. Manufacturers who created Windows RT devices have criticized it in the media and stated they have no plans to produce any future Windows RT devices. The only Windows RT devices still on the market are Microsoft’s Surface (originally named Surface RT) and Surface 2. Nokia is also coming out with their own Windows RT tablet, but they’re in the process of being purchased by Microsoft. In other words, Windows RT just isn’t a factor when it comes to bloatware — you wouldn’t get a Windows RT device unless you purchased a Surface, but those wouldn’t come with bloatware anyway. Removing Bloatware or Reinstalling Windows 8.1 While bloatware is still a problem on new Windows systems and the Refresh option probably won’t help you, you can still eliminate bloatware in the traditional way. Bloatware can be uninstalled from the Windows Control Panel or with a dedicated removal tool like PC Decrapifier, which tries to automatically uninstall the junk for you. You can also do what Windows geeks have always tended to do with new computers — reinstall Windows 8 or 8.1 from scratch with installation media from Microsoft. You’ll get a clean Windows system and you can install only the hardware drivers and other software you need. Unfortunately, bloatware is still a big problem for Windows PCs. Windows 8 tries to do some things to address bloatware, but it ultimately comes up short. Most Windows PCs sold in most stores to most people will still have the typical bloatware slowing down the boot process, wasting memory, and adding clutter. Image Credit: LG on Flickr, Intel Free Press on Flickr, Wilson Hui on Flickr, Intel Free Press on Flickr, Vernon Chan on Flickr     

    Read the article

  • FAQ: GridView Calculation with JavaScript

    - by Vincent Maverick Durano
    In my previous post I wrote a simple demo on how to Calculate Totals in GridView and Display it in the Footer. Basically what it does is it calculates the total amount by typing into the TextBox and display the grand total in the footer of the GridView and basically it was a server side implemenation.  Many users in the forums are asking how to do the same thing without postbacks and how to calculate both amount and total amount together. In this post I will demonstrate how to do this using JavaScript. To get started let's go ahead and set up the form. Just for the simplicity of this demo I just set up the form like this:   <asp:gridview ID="GridView1" runat="server" ShowFooter="true" AutoGenerateColumns="false"> <Columns> <asp:BoundField DataField="RowNumber" HeaderText="Row Number" /> <asp:BoundField DataField="Description" HeaderText="Item Description" /> <asp:TemplateField HeaderText="Item Price"> <ItemTemplate> <asp:Label ID="LBLPrice" runat="server" Text='<%# Eval("Price") %>'></asp:Label> </ItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Quantity"> <ItemTemplate> <asp:TextBox ID="TXTQty" runat="server"></asp:TextBox> </ItemTemplate> <FooterTemplate> <b>Total Amount:</b> </FooterTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Sub-Total"> <ItemTemplate> <asp:Label ID="LBLSubTotal" runat="server"></asp:Label> </ItemTemplate> <FooterTemplate> <asp:Label ID="LBLTotal" runat="server" ForeColor="Green"></asp:Label> </FooterTemplate> </asp:TemplateField> </Columns> </asp:gridview>   As you can see there's no fancy about the mark up above. It just a standard GridView with BoundFields and TemplateFields on it. Now just for the purpose of this demo I just use a dummy data for populating the GridView. Here's the code below:   public partial class GridCalculation : System.Web.UI.Page { private void BindDummyDataToGrid() { DataTable dt = new DataTable(); DataRow dr = null; dt.Columns.Add(new DataColumn("RowNumber", typeof(string))); dt.Columns.Add(new DataColumn("Description", typeof(string))); dt.Columns.Add(new DataColumn("Price", typeof(string))); dr = dt.NewRow(); dr["RowNumber"] = 1; dr["Description"] = "Nike"; dr["Price"] = "1000"; dt.Rows.Add(dr); dr = dt.NewRow(); dr["RowNumber"] = 2; dr["Description"] = "Converse"; dr["Price"] = "800"; dt.Rows.Add(dr); dr = dt.NewRow(); dr["RowNumber"] = 3; dr["Description"] = "Adidas"; dr["Price"] = "500"; dt.Rows.Add(dr); dr = dt.NewRow(); dr["RowNumber"] = 4; dr["Description"] = "Reebok"; dr["Price"] = "750"; dt.Rows.Add(dr); dr = dt.NewRow(); dr["RowNumber"] = 5; dr["Description"] = "Vans"; dr["Price"] = "1100"; dt.Rows.Add(dr); dr = dt.NewRow(); dr["RowNumber"] = 6; dr["Description"] = "Fila"; dr["Price"] = "200"; dt.Rows.Add(dr); //Bind the Gridview GridView1.DataSource = dt; GridView1.DataBind(); } protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { BindDummyDataToGrid(); } } }   Now try to run the page. The output should look something like below: The Client-Side Calculation Here's the code for the GridView calculation:   <script type="text/javascript"> function CalculateTotals() { var gv = document.getElementById("<%= GridView1.ClientID %>"); var tb = gv.getElementsByTagName("input"); var lb = gv.getElementsByTagName("span"); var sub = 0; var total = 0; var indexQ = 1; var indexP = 0; for (var i = 0; i < tb.length; i++) { if (tb[i].type == "text") { sub = parseFloat(lb[indexP].innerHTML) * parseFloat(tb[i].value); if (isNaN(sub)) { lb[i + indexQ].innerHTML = ""; sub = 0; } else { lb[i + indexQ].innerHTML = sub; } indexQ++; indexP = indexP + 2; total += parseFloat(sub); } } lb[lb.length -1].innerHTML = total; } </script>   The code above calculates the sub-total by multiplying the price and the quantity and at the same time calculates the total amount  by adding the sub-total values. Now you can simply call the JavaScript function above like this:   <ItemTemplate> <asp:TextBox ID="TXTQty" runat="server" onkeyup="CalculateTotals();"></asp:TextBox> </ItemTemplate>   Running the code above will display something like below: That's it! I hope someone find this post useful! Technorati Tags: ASP.NET,JavaScript,GridView,TipsTricks

    Read the article

  • FAQ: GridView Calculation with JavaScript - Formatting and Validation

    - by Vincent Maverick Durano
    In my previous post here we've talked about how to calculate the sub-totals and grand total in GridView using JavaScript. In this post I'm going take more step further and will demonstrate how are we going to format the totals into a currency and how to validate the input that would only allow you to enter a whole number in the quantity TextBox. Here are the code blocks below: ASPX Source:   <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title></title> <script type="text/javascript"> function CalculateTotals() { var gv = document.getElementById("<%= GridView1.ClientID %>"); var tb = gv.getElementsByTagName("input"); var lb = gv.getElementsByTagName("span"); var sub = 0; var total = 0; var indexQ = 1; var indexP = 0; var price = 0; for (var i = 0; i < tb.length; i++) { if (tb[i].type == "text") { ValidateNumber(tb[i]); price = lb[indexP].innerHTML.replace("$", "").replace(",", ""); sub = parseFloat(price) * parseFloat(tb[i].value); if (isNaN(sub)) { lb[i + indexQ].innerHTML = "0.00"; sub = 0; } else { lb[i + indexQ].innerHTML = FormatToMoney(sub, "$", ",", "."); ; } indexQ++; indexP = indexP + 2; total += parseFloat(sub); } } lb[lb.length - 1].innerHTML = FormatToMoney(total, "$", ",", "."); } function ValidateNumber(o) { if (o.value.length > 0) { o.value = o.value.replace(/[^\d]+/g, ''); //Allow only whole numbers } } function isThousands(position) { if (Math.floor(position / 3) * 3 == position) return true; return false; }; function FormatToMoney(theNumber, theCurrency, theThousands, theDecimal) { var theDecimalDigits = Math.round((theNumber * 100) - (Math.floor(theNumber) * 100)); theDecimalDigits = "" + (theDecimalDigits + "0").substring(0, 2); theNumber = "" + Math.floor(theNumber); var theOutput = theCurrency; for (x = 0; x < theNumber.length; x++) { theOutput += theNumber.substring(x, x + 1); if (isThousands(theNumber.length - x - 1) && (theNumber.length - x - 1 != 0)) { theOutput += theThousands; }; }; theOutput += theDecimal + theDecimalDigits; return theOutput; } </script> </head> <body> <form id="form1" runat="server"> <asp:gridview ID="GridView1" runat="server" ShowFooter="true" AutoGenerateColumns="false"> <Columns> <asp:BoundField DataField="RowNumber" HeaderText="Row Number" /> <asp:BoundField DataField="Description" HeaderText="Item Description" /> <asp:TemplateField HeaderText="Item Price"> <ItemTemplate> <asp:Label ID="LBLPrice" runat="server" Text='<%# Eval("Price","{0:C}") %>'></asp:Label> </ItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Quantity"> <ItemTemplate> <asp:TextBox ID="TXTQty" runat="server" onkeyup="CalculateTotals();"></asp:TextBox> </ItemTemplate> <FooterTemplate> <b>Total Amount:</b> </FooterTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Sub-Total"> <ItemTemplate> <asp:Label ID="LBLSubTotal" runat="server" ForeColor="Green" Text="0.00"></asp:Label> </ItemTemplate> <FooterTemplate> <asp:Label ID="LBLTotal" runat="server" ForeColor="Green" Font-Bold="true" Text="0.00"></asp:Label> </FooterTemplate> </asp:TemplateField> </Columns> </asp:gridview> </form> </body> </html> Code Behind Source:   public partial class GridCalculation : System.Web.UI.Page { private void BindDummyDataToGrid() { DataTable dt = new DataTable(); DataRow dr = null; dt.Columns.Add(new DataColumn("RowNumber", typeof(string))); dt.Columns.Add(new DataColumn("Description", typeof(string))); dt.Columns.Add(new DataColumn("Price", typeof(decimal))); dr = dt.NewRow(); dr["RowNumber"] = 1; dr["Description"] = "Nike"; dr["Price"] = "1000"; dt.Rows.Add(dr); dr = dt.NewRow(); dr["RowNumber"] = 2; dr["Description"] = "Converse"; dr["Price"] = "800"; dt.Rows.Add(dr); dr = dt.NewRow(); dr["RowNumber"] = 3; dr["Description"] = "Adidas"; dr["Price"] = "500"; dt.Rows.Add(dr); dr = dt.NewRow(); dr["RowNumber"] = 4; dr["Description"] = "Reebok"; dr["Price"] = "750"; dt.Rows.Add(dr); dr = dt.NewRow(); dr["RowNumber"] = 5; dr["Description"] = "Vans"; dr["Price"] = "1100"; dt.Rows.Add(dr); dr = dt.NewRow(); dr["RowNumber"] = 6; dr["Description"] = "Fila"; dr["Price"] = "200"; dt.Rows.Add(dr); //Bind the Gridview GridView1.DataSource = dt; GridView1.DataBind(); } protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { BindDummyDataToGrid(); } } } Running the code above will display something like this: On initial load After entering the quantity in the TextBox That's it! I hope someone find this post useful! Technorati Tags: ASP.NET,C#,ADO.NET,JavaScript,GridView

    Read the article

  • Is Berkeley DB a NoSQL solution?

    - by Gregory Burd
    Berkeley DB is a library. To use it to store data you must link the library into your application. You can use most programming languages to access the API, the calls across these APIs generally mimic the Berkeley DB C-API which makes perfect sense because Berkeley DB is written in C. The inspiration for Berkeley DB was the DBM library, a part of the earliest versions of UNIX written by AT&T's Ken Thompson in 1979. DBM was a simple key/value hashtable-based storage library. In the early 1990s as BSD UNIX was transitioning from version 4.3 to 4.4 and retrofitting commercial code owned by AT&T with unencumbered code, it was the future founders of Sleepycat Software who wrote libdb (aka Berkeley DB) as the replacement for DBM. The problem it addressed was fast, reliable local key/value storage. At that time databases almost always lived on a single node, even the most sophisticated databases only had simple fail-over two node solutions. If you had a lot of data to store you would choose between the few commercial RDBMS solutions or to write your own custom solution. Berkeley DB took the headache out of the custom approach. These basic market forces inspired other DBM implementations. There was the "New DBM" (ndbm) and the "GNU DBM" (GDBM) and a few others, but the theme was the same. Even today TokyoCabinet calls itself "a modern implementation of DBM" mimicking, and improving on, something first created over thirty years ago. In the mid-1990s, DBM was the name for what you needed if you were looking for fast, reliable local storage. Fast forward to today. What's changed? Systems are connected over fast, very reliable networks. Disks are cheep, fast, and capable of storing huge amounts of data. CPUs continued to follow Moore's Law, processing power that filled a room in 1990 now fits in your pocket. PCs, servers, and other computers proliferated both in business and the personal markets. In addition to the new hardware entire markets, social systems, and new modes of interpersonal communication moved onto the web and started evolving rapidly. These changes cause a massive explosion of data and a need to analyze and understand that data. Taken together this resulted in an entirely different landscape for database storage, new solutions were needed. A number of novel solutions stepped up and eventually a category called NoSQL emerged. The new market forces inspired the CAP theorem and the heated debate of BASE vs. ACID. But in essence this was simply the market looking at what to trade off to meet these new demands. These new database systems shared many qualities in common. There were designed to address massive amounts of data, millions of requests per second, and scale out across multiple systems. The first large-scale and successful solution was Dynamo, Amazon's distributed key/value database. Dynamo essentially took the next logical step and added a twist. Dynamo was to be the database of record, it would be distributed, data would be partitioned across many nodes, and it would tolerate failure by avoiding single points of failure. Amazon did this because they recognized that the majority of the dynamic content they provided to customers visiting their web store front didn't require the services of an RDBMS. The queries were simple, key/value look-ups or simple range queries with only a few queries that required more complex joins. They set about to use relational technology only in places where it was the best solution for the task, places like accounting and order fulfillment, but not in the myriad of other situations. The success of Dynamo, and it's design, inspired the next generation of Non-SQL, distributed database solutions including Cassandra, Riak and Voldemort. The problem their designers set out to solve was, "reliability at massive scale" so the first focal point was distributed database algorithms. Underneath Dynamo there is a local transactional database; either Berkeley DB, Berkeley DB Java Edition, MySQL or an in-memory key/value data structure. Dynamo was an evolution of local key/value storage onto networks. Cassandra, Riak, and Voldemort all faced similar design decisions and one, Voldemort, choose Berkeley DB Java Edition for it's node-local storage. Riak at first was entirely in-memory, but has recently added write-once, append-only log-based on-disk storage similar type of storage as Berkeley DB except that it is based on a hash table which must reside entirely in-memory rather than a btree which can live in-memory or on disk. Berkeley DB evolved too, we added high availability (HA) and a replication manager that makes it easy to setup replica groups. Berkeley DB's replication doesn't partitioned the data, every node keeps an entire copy of the database. For consistency, there is a single node where writes are committed first - a master - then those changes are delivered to the replica nodes as log records. Applications can choose to wait until all nodes are consistent, or fire and forget allowing Berkeley DB to eventually become consistent. Berkeley DB's HA scales-out quite well for read-intensive applications and also effectively eliminates the central point of failure by allowing replica nodes to be elected (using a PAXOS algorithm) to mastership if the master should fail. This implementation covers a wide variety of use cases. MemcacheDB is a server that implements the Memcache network protocol but uses Berkeley DB for storage and HA to replicate the cache state across all the nodes in the cache group. Google Accounts, the user authentication layer for all Google properties, was until recently running Berkeley DB HA. That scaled to a globally distributed system. That said, most NoSQL solutions try to partition (shard) data across nodes in the replication group and some allow writes as well as reads at any node, Berkeley DB HA does not. So, is Berkeley DB a "NoSQL" solution? Not really, but it certainly is a component of many of the existing NoSQL solutions out there. Forgetting all the noise about how NoSQL solutions are complex distributed databases when you boil them down to a single node you still have to store the data to some form of stable local storage. DBMs solved that problem a long time ago. NoSQL has more to do with the layers on top of the DBM; the distributed, sometimes-consistent, partitioned, scale-out storage that manage key/value or document sets and generally have some form of simple HTTP/REST-style network API. Does Berkeley DB do that? Not really. Is Berkeley DB a "NoSQL" solution today? Nope, but it's the most robust solution on which to build such a system. Re-inventing the node-local data storage isn't easy. A lot of people are starting to come to appreciate the sophisticated features found in Berkeley DB, even mimic them in some cases. Could Berkeley DB grow into a NoSQL solution? Absolutely. Our key/value API could be extended over the net using any of a number of existing network protocols such as memcache or HTTP/REST. We could adapt our node-local data partitioning out over replicated nodes. We even have a nice query language and cost-based query optimizer in our BDB XML product that we could reuse were we to build out a document-based NoSQL-style product. XML and JSON are not so different that we couldn't adapt one to work with the other interchangeably. Without too much effort we could add what's missing, we could jump into this No SQL market withing a single product development cycle. Why isn't Berkeley DB already a NoSQL solution? Why aren't we working on it? Why indeed...

    Read the article

  • Code excavations, wishful invocations, perimeters and domain specific unit test frameworks

    - by RoyOsherove
    One of the talks I did at QCON London was about a subject that I’ve come across fairly recently , when I was building SilverUnit – a “pure” unit test framework for silverlight objects that depend on the silverlight runtime to run. It is the concept of “cogs in the machine” – when your piece of code needs to run inside a host framework or runtime that you have little or no control over for testability related matters. Examples of such cogs and machines can be: your custom control running inside silverlight runtime in the browser your plug-in running inside an IDE your activity running inside a windows workflow your code running inside a java EE bean your code inheriting from a COM+ (enterprise services) component etc.. Not all of these are necessarily testability problems. The main testability problem usually comes when your code actually inherits form something inside the system. For example. one of the biggest problems with testing objects like silverlight controls is the way they depend on the silverlight runtime – they don’t implement some silverlight interface, they don’t just call external static methods against the framework runtime that surrounds them – they actually inherit parts of the framework: they all inherit (in this case) from the silverlight DependencyObject Wrapping it up? An inheritance dependency is uniquely challenging to bring under test, because “classic” methods such as wrapping the object under test with a framework wrapper will not work, and the only way to do manually is to create parallel testable objects that get delegated with all the possible actions from the dependencies.    In silverlight’s case, that would mean creating your own custom logic class that would be called directly from controls that inherit from silverlight, and would be tested independently of these controls. The pro side is that you get the benefit of understanding the “contract” and the “roles” your system plays against your logic, but unfortunately, more often than not, it can be very tedious to create, and may sometimes feel unnecessary or like code duplication. About perimeters A perimeter is that invisible line that your draw around your pieces of logic during a test, that separate the code under test from any dependencies that it uses. Most of the time, a test perimeter around an object will be the list of seams (dependencies that can be replaced such as interfaces, virtual methods etc.) that are actually replaced for that test or for all the tests. Role based perimeters In the case of creating a wrapper around an object – one really creates a “role based” perimeter around the logic that is being tested – that wrapper takes on roles that are required by the code under test, and also communicates with the host system to implement those roles and provide any inputs to the logic under test. in the image below – we have the code we want to test represented as a star. No perimeter is drawn yet (we haven’t wrapped it up in anything yet). in the image below is what happens when you wrap your logic with a role based wrapper – you get a role based perimeter anywhere your code interacts with the system: There’s another way to bring that code under test – using isolation frameworks like typemock, rhino mocks and MOQ (but if your code inherits from the system, Typemock might be the only way to isolate the code from the system interaction.   Ad-Hoc Isolation perimeters the image below shows what I call ad-hoc perimeter that might be vastly different between different tests: This perimeter’s surface is much smaller, because for that specific test, that is all the “change” that is required to the host system behavior.   The third way of isolating the code from the host system is the main “meat” of this post: Subterranean perimeters Subterranean perimeters are Deep rooted perimeters  - “always on” seams that that can lie very deep in the heart of the host system where they are fully invisible even to the test itself, not just to the code under test. Because they lie deep inside a system you can’t control, the only way I’ve found to control them is with runtime (not compile time) interception of method calls on the system. One way to get such abilities is by using Aspect oriented frameworks – for example, in SilverUnit, I’ve used the CThru AOP framework based on Typemock hooks and CLR profilers to intercept such system level method calls and effectively turn them into seams that lie deep down at the heart of the silverlight runtime. the image below depicts an example of what such a perimeter could look like: As you can see, the actual seams can be very far away form the actual code under test, and as you’ll discover, that’s actually a very good thing. Here is only a partial list of examples of such deep rooted seams : disabling the constructor of a base class five levels below the code under test (this.base.base.base.base) faking static methods of a type that’s being called several levels down the stack: method x() calls y() calls z() calls SomeType.StaticMethod()  Replacing an async mechanism with a synchronous one (replacing all timers with your own timer behavior that always Ticks immediately upon calls to “start()” on the same caller thread for example) Replacing event mechanisms with your own event mechanism (to allow “firing” system events) Changing the way the system saves information with your own saving behavior (in silverunit, I replaced all Dependency Property set and get with calls to an in memory value store instead of using the one built into silverlight which threw exceptions without a browser) several questions could jump in: How do you know what to fake? (how do you discover the perimeter?) How do you fake it? Wouldn’t this be problematic  - to fake something you don’t own? it might change in the future How do you discover the perimeter to fake? To discover a perimeter all you have to do is start with a wishful invocation. a wishful invocation is the act of trying to invoke a method (or even just create an instance ) of an object using “regular” test code. You invoke the thing that you’d like to do in a real unit test, to see what happens: Can I even create an instance of this object without getting an exception? Can I invoke this method on that instance without getting an exception? Can I verify that some call into the system happened? You make the invocation, get an exception (because there is a dependency) and look at the stack trace. choose a location in the stack trace and disable it. Then try the invocation again. if you don’t get an exception the perimeter is good for that invocation, so you can move to trying out other methods on that object. in a future post I will show the process using CThru, and how you end up with something close to a domain specific test framework after you’re done creating the perimeter you need.

    Read the article

  • CodePlex Daily Summary for Sunday, April 18, 2010

    CodePlex Daily Summary for Sunday, April 18, 2010New ProjectsBare Bones Email Trace Listener: Bare Bones Email Trace Listener is about the simplest email trace listener you can have. No bells, no whistles, and no good if you need authenticat...Cartellino: Scopo del progetto è la realizzazione di un software in grado di rilevare i dati dai rilevatori 3Tec (www.3tec.it) e stampare i cartellini presenza...Castle Windsor app.config Properties: The Castle Windsor app.config Properties library makes it possible for users of Castle Windsor to reference appSettings values in Windsor's XML pro...DeskD: This is a simple desktop dictionary application(something like WordWeb) created in Java using Netbeans IDE. Since i am new to codeplex all updates ...FunPokerMakerOnline: It is a play of poker online with a game editor. It is done with .net 4 and WPF and SOAP or WCF. KLOCS Team GIN Project: This is a Master's Degree program group project. It may have academic interest, but won't be maintained after June 2010KNN: This is KNN projectProject Santa: Program to organize teams using mysql databases and c# in a clean and robust task and group system. For more information see my blog post at http:/...ProjetoIntegradoJuridico: Sistema Integrado de Acompanhamento JurídicoRSSR for Windows Phone 7: This is a simple RSS reader application, the project aims to show people that it is easy to build application for windows phones. The applicatio...Simple Rcon: Simple Rcon is a simple lightweight rcon client for HL1/HL2 Servers. It is developed in C# and WPFTAB METHOD SQL Create a data dictionary from your Transact SQL code: TABMETHODSQL makes it easier for data/information workers to document their work. Create a data governance solution that maps sql data process, inc...TM BF Tournament: WPF software to manage Trackmania tournament with Battle France RulesviBlog: visinia plugin, this plugin is used to add blogging facility in visinia cmsviNews: visinia plugin, this plugin can be used to create a news portal like cnn.com nytimeVolumeMaster: VolumeMaster is an On Screen Display (OSD) that gets activated whenever the volume changes. It's written in WPF and uses Vista Core Audio API by Ra...WiiCIS.NET: This is a managed port of WiiCIS, which is a Nintendo Wiimote library originally created by TheOboeNerd and posted on Sourceforge.New ReleasesCastle Windsor app.config Properties: Version 1.0: Initial release.Code for Rapid C# Windows Development eBook: Enumerable Debugger Visualizer Version 1.1: Second release of the Enumerable Debugger Visualizer. There are more classes registered and it is more robust. The list of classes I have register...Convection Game Engine (Basic Edition): Convection Basic (40223): Compiled version of Convection Basic change set 40223.CycleMania Starter Kit EAP - ASP.NET 4 Problem - Design - Solution: Cyclemania 0.08.59: See Source Code tab for recent change history.DbEntry.Net (Lephone Framework): DbEntry.Net 3.9: DbEntry.Net is a lightweight Object Relational Mapping (ORM) database access compnent for .Net 3.5. It has clearly and easily programing interface ...Hash Calculator: HashCalculator 2.0: Upgraded to .NET Framework 4.0 Added support to calculate CRC32 hash function Added "Cancel" button in the Windows 7 taskbar thumbnailHKGolden Express: HKGoldenExpress (Build 201004172120): New features: Added jump links at top of page of message. Bug fix: Fixed page count bug. Improvements: HKGolden Express now uses DocumentBuild...HTML Ruby: 6.21.4: Styles added to override those on some sites for better rendering of ruby Fix regression on complex ruby annotation rendering Better spacingHTML Ruby: 6.21.5: Removed debug code in preference handling Status bar indicator now resets for each action Replace ruby in place without using document fragment...IceChat: IceChat 2009 Alpha 12.4 EXE Update: This is simply an update to the main IceChat program files and DLL. Simpply overwrite the ones in the place where IceChat 2009 is installed.IceChat: IceChat 2009 Alpha 12.4 Full Install: Build Alpha 12.4 - April 17 2010 Added IceChatScript.dll , needs to be added in same folder with EXE and IPluginIceChat.dll Added Self Notice in ...PokeIn Comet Ajax Library: PokeIn Library v05 x64: With this version, PokeIn library has become a stable. Numerous tests have completed. This is the first release candidate of PokeIn. Cheers!PokeIn Comet Ajax Library: PokeIn Library v05 x86: PokeIn Library version 0.5 (x86) With this version, PokeIn library has become a stable. Numerous tests have completed. This is the first release c...Project Santa: Project Santa V1.0: The first initial release of my project manager program, for more information see http://coderplex.blogspot.com/2010/04/project-manager-using-mysq...Salient: TestingWithVSDevServer v1: Using code from Salient, I have assembled a few strategies for programmatic contol of the Visual Studio Development Server (WebDev.WebServer.exe). ...SharePoint Navigation Menu: spNavigationMenu 1.1: Changed the CAML query so it will order by Link Order, then Title. Added the ability to override the On Hover event on the parent menu to use On ...Simple Rcon: Simple Rcon Version 1: Version 1TAB METHOD SQL Create a data dictionary from your Transact SQL code: RELEASE 1: TESTING THE RELEASE SYSTEMTribe.Cache: Tribe.Cache Beta 0.1: Beta release of Tribe.Cache - Now with cache expiration serviceviBlog: viBlog_beta: visinia plugin to add blogging facility in visinia cmsviNews: viNews_beta: visinia plugin.visinia: visinia_beta2: visinia beta 2 released with many new feature.Visual Studio DSite: Visual C++ 2008 Login Form: A simple login form made in visual c 2008. Source code only.WiiCIS.NET: WiiCIS.NET v0.11: 0.11 Removed an unnecessary function from the Wiimote class, and improved the demo. You will need the latest version of SlimDX to compile the sourc...WinControls TreeListView: TreeListView 1.5.1: -fixes issue #5837 -Preliminary feature #5874WoW Character Viewer: Viewer Setup: Finally, I've brought out the next setup of WoW Viewer. Most loose ends have been tied up. Loading and Saving of character files has been fixed.Most Popular ProjectsRawrAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseMicrosoft SQL Server Community & Samplespatterns & practices – Enterprise LibraryPHPExcelFacebook Developer ToolkitBlogEngine.NETMvcContrib: a Codeplex Foundation projectIronPythonMost Active ProjectsRawrpatterns & practices – Enterprise LibraryIndustrial DashboardFarseer Physics EnginejQuery Library for SharePoint Web ServicesIonics Isapi Rewrite FilterGMap.NET - Great Maps for Windows Forms & PresentationProxi [Proxy Interface]BlogEngine.NETCaliburn: An Application Framework for WPF and Silverlight

    Read the article

  • Reading All Users Session

    - by imran_ku07
      Introduction :            InProc Session is the widely used state management. Storing the session state Inproc is also the fastest method and is well-suited to small amounts of volatile data. Reading and writing current user Session is very easy. But some times we need to read all users session before taking a decision or sometimes we may need to check which users are currently active with the help of Session. But unfortunately there is no class in .Net Framework (i don't found myself) to read all user InProc Session Data. In this article i will use reflection to read all user Inproc Session.   Description :              This code will work equally in both MVC and webform, but for demonstration i will use a simple webform example. So let's create a simple Website and Add two aspx pages, Default.aspx and Default2.aspx. In Default.aspx just add a link to navigate to Default2.aspx and in Default.aspx.cs just add a Session. Default.aspx: <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="Default" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html ><head runat="server">    <title>Untitled Page</title></head><body>    <form id="form1" runat="server">    <div>        <a href="Default2.aspx">Click to navigate to next page</a>    </div>    </form></body></html>  Default.aspx.cs:  using System;using System.Data;using System.Configuration;using System.Collections;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Web.UI.HtmlControls;public partial class Default : System.Web.UI.Page{    protected void Page_Load(object sender, EventArgs e)    {        Session["User"] = "User" + DateTime.Now;    }} Now when every user click this link will navigate to Default2.aspx where all the magic appears.Default2.aspx.cs: using System;using System.Data;using System.Configuration;using System.Collections;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Web.UI.HtmlControls;using System.Reflection;using System.Web.SessionState;public partial class Default2 : System.Web.UI.Page{    protected void Page_Load(object sender, EventArgs e)    {        object obj = typeof(HttpRuntime).GetProperty("CacheInternal", BindingFlags.NonPublic | BindingFlags.Static).GetValue(null, null);        Hashtable c2 = (Hashtable)obj.GetType().GetField("_entries", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(obj);        foreach (DictionaryEntry entry in c2)        {            object o1 = entry.Value.GetType().GetProperty("Value", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(entry.Value, null);            if (o1.GetType().ToString() == "System.Web.SessionState.InProcSessionState")            {                SessionStateItemCollection sess = (SessionStateItemCollection)o1.GetType().GetField("_sessionItems", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(o1);                if (sess != null)                {                    if (sess["User"] != null)                    {                        Label1.Text += sess["User"] + " is Active.<br>";                    }                }            }        }    }}            Now just open more than one browsers or more than one browser instance and then navigate to Default.aspx and click the link, you will see all the user's Session data.    How this works :        InProc session data is stored in the HttpRuntime’s internal cache in an implementation of ISessionStateItemCollection that implements ICollection. In this code, first of all i got CacheInternal Static Property of HttpRuntime class and then with the help of this object i got _entries private member which is of type ICollection. Then simply enumerate this dictionary and only take object of type System.Web.SessionState.InProcSessionState and finaly got SessionStateItemCollection for each user.Summary :        In this article, I shows you how you can get all current user Sessions. However one thing you will find when executing this code is that it will not show the current user Session which is set in the current request context because Session will be saved after all the Page Events.

    Read the article

  • How-to tell the ViewCriteria a user chose in an af:query component

    - by frank.nimphius
    Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The af:query component defines a search form for application users to enter search conditions for a selected View Criteria. A View Criteria is a named where clauses that you can create declaratively on the ADF Business Component View Object. A default View Criteria that allows users to search in all attributes exists by default and exposed in the Data Controls panel. To create an ADF Faces search form, expand the View Object node that contains the View Criteria definition in the Data Controls panel. Drag the View Criteria that should be displayed as the default criteria onto the page and choose Query in the opened context menu. One of the options within the Query option is to create an ADF Query Panel with Table, which displays the result set in a table view, which can have additional column filters defined. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} To intercept the user query for modification, or just to know about the selected View Criteria, you override the QueryListener property on the af:query component of the af:table component. Overriding the QueryListener on the table makes sense if the table allows users to further filter the result set using column filters.To override the default QueryListener, copy the existing string referencing the binding layer to the clipboard and then select Edit from the field context menu (press the arrow icon to open it) to selecte or create a new managed bean and method to handle the query event.  The code below is from a managed bean with custom query listener handlers defined for the af:query component and the af:table component. The default listener entry copied to the clipboard was "#{bindings.ImplicitViewCriteriaQuery.processQuery}"  public void onQueryList(QueryEvent queryEvent) {   // The generated QueryListener replaced by this method   //#{bindings.ImplicitViewCriteriaQuery.processQuery}        QueryDescriptor qdes = queryEvent.getDescriptor();          //print or log selected View Criteria   System.out.println("NAME "+qdes.getName());           //call default Query Event        invokeQueryEventMethodExpression("      #{bindings.ImplicitViewCriteriaQuery.processQuery}",queryEvent);  } public void onQueryTable(QueryEvent queryEvent) {   // The generated QueryListener replaced by this method   //#{bindings.ImplicitViewCriteriaQuery.processQuery}   QueryDescriptor qdes = queryEvent.getDescriptor();   //print or log selected View Criteria   System.out.println("NAME "+qdes.getName());                   invokeQueryEventMethodExpression(     "#{bindings.ImplicitViewCriteriaQuery.processQuery}",queryEvent); } private void invokeQueryEventMethodExpression(                        String expression, QueryEvent queryEvent){   FacesContext fctx = FacesContext.getCurrentInstance();   ELContext elctx = fctx.getELContext();   ExpressionFactory efactory   fctx.getApplication().getExpressionFactory();     MethodExpression me =     efactory.createMethodExpression(elctx,expression,                                     Object.class,                                     new Class[]{QueryEvent.class});     me.invoke(elctx, new Object[]{queryEvent}); } Of course, this code also can be used as a starting point for other query manipulations and also works with saved custom criterias. To read more about the af:query component, see: http://download.oracle.com/docs/cd/E15523_01/apirefs.1111/e12419/tagdoc/af_query.html

    Read the article

  • Azure, don't give me multiple VMs, give me one elastic VM

    - by FransBouma
    Yesterday, Microsoft revealed new major features for Windows Azure (see ScottGu's post). It all looks shiny and great, but after reading most of the material describing the new features, I still find the overall idea behind all of it flawed: why should I care on how much VMs my web app runs? Isn't that a problem to solve for the Windows Azure engineers / software? And what if I need the file system, why can't I simply get a virtual filesystem ? To illustrate my point, let's use a real example: a product website with a customer system/database and next to it a support site with accompanying database. Both are written in .NET, using ASP.NET and use a SQL Server database each. The product website offers files to download by customers, very simple. You have a couple of options to host these websites: Buy a server, place it in a rack at an ISP and run the sites on that server Use 'shared hosting' with an ISP, which means your sites' appdomains are running on the same machine, as well as the files stored, and the databases are hosted in the same server as the other shared databases. Hire a VM, install your OS of choice at an ISP, and host the sites on that VM, basically the same as the first option, except you don't have a physical server At some cloud-vendor, either host the sites 'shared' or in a VM. See above. With all of those options, scalability is a problem, even the cloud-based ones, though not due to the same reasons: The physical server solution has the obvious problem that if you need more power, you need to buy a bigger server or more servers which requires you to add replication and other overhead Shared hosting solutions are almost always capped on memory usage / traffic and database size: if your sites get too big, you have to move out of the shared hosting environment and start over with one of the other solutions The VM solution, be it a VM at an ISP or 'in the cloud' at e.g. Windows Azure or Amazon, in theory allows scaling out by simply instantiating more VMs, however that too introduces the same overhead problems as with the physical servers: suddenly more than 1 instance runs your sites. If a cloud vendor offers its services in the form of VMs, you won't gain much over having a VM at some ISP: the main problems you have to work around are still there: when you spin up more than one VM, your application must be completely stateless at any moment, including the DB sub system, because what's in memory in instance 1 might not be in memory in instance 2. This might sounds trivial but it's not. A lot of the websites out there started rather small: they were perfectly runnable on a single machine with normal memory and CPU power. After all, you don't need a big machine to run a website with even thousands of users a day. Moving these sites to a multi-VM environment will cause a problem: all the in-memory state they use, all the multi-page transitions they use while keeping state across the transition, they can't do that anymore like they did that on a single machine: state is something of the past, you have to store every byte of state in either a DB or in a viewstate or in a cookie somewhere so with the next request, all state information is available through the request, as nothing is kept in-memory. Our example uses a bunch of files in a file system. Using multiple VMs will require that these files move to a cloud storage system which is mounted in each VM so we don't have to store the files on each VM. This might require different file paths, but this change should be minor. What's perhaps less minor is the maintenance procedure in place on the new type of cloud storage used: instead of ftp-ing into a VM, you might have to update the files using different ways / tools. All in all this makes moving an existing website which was written for an environment that's based around a VM (namely .NET with its CLR) overly cumbersome and problematic: it forces you to refactor your website system to be able to be used 'in the cloud', which is caused by the limited way how e.g. Windows Azure offers its cloud services: in blocks of VMs. Offer a scalable, flexible VM which extends with my needs Instead, cloud vendors should offer simply one VM to me. On that VM I run the websites, store my DB and my files. As it's a virtual machine, how this machine is actually ran on physical hardware (e.g. partitioned), I don't care, as that's the problem for the cloud vendor to solve. If I need more resources, e.g. I have more traffic to my server, way more visitors per day, the VM stretches, like I bought a bigger box. This frees me from the problem which comes with multiple VMs: I don't have any refactoring to do at all: I can simply build my website as if it runs on my local hardware server, upload it to the VM offered by the cloud vendor, install it on the VM and I'm done. "But that might require changes to windows!" Yes, but Microsoft is Windows. Windows Azure is their service, they can make whatever change to what they offer to make it look like it's windows. Yet, they're stuck, like Amazon, in thinking in VMs, which forces developers to 'think ahead' and gamble whether they would need to migrate to a cloud with multiple VMs in the future or not. Which comes down to: gamble whether they should invest time in code / architecture which they might never need. (YAGNI anyone?) So the VM we're talking about, is that a low-level VM which runs a guest OS, or is that VM a different kind of VM? The flexible VM: .NET's CLR ? My example websites are ASP.NET based, which means they run inside a .NET appdomain, on the .NET CLR, which is a VM. The only physical OS resource the sites need is the file system, however this too is accessed through .NET. In short: all the websites see is what .NET allows the websites to see, the world as the websites know it is what .NET shows them and lets them access. How the .NET appdomain is run physically, that's the concern of .NET, not mine. This begs the question why Windows Azure doesn't offer virtual appdomains? Or better: .NET environments which look like one machine but could be physically multiple machines. In such an environment, no change has to be made to the websites to migrate them from a local machine or own server to the cloud to get proper scaling: the .NET VM will simply scale with the need: more memory needed, more CPU power needed, it stretches. What it offers to the application running inside the appdomain is simply increasing, but not fragmented: all resources are available to the application: this means that the problem of how to scale is back to where it should be: with the cloud vendor. "Yeah, great, but what about the databases?" The .NET application communicates with the database server through a .NET ADO.NET provider. Where the database is located is not a problem of the appdomain: the ADO.NET provider has to solve that. I.o.w.: we can host the databases in an environment which offers itself as a single resource and is accessible through one connection string without replication overhead on the outside, and use that environment inside the .NET VM as if it was a single DB. But what about memory replication and other problems? This environment isn't simple, at least not for the cloud vendor. But it is simple for the customer who wants to run his sites in that cloud: no work needed. No refactoring needed of existing code. Upload it, run it. Perhaps I'm dreaming and what I described above isn't possible. Yet, I think if cloud vendors don't move into that direction, what they're offering isn't interesting: it doesn't solve a problem at all, it simply offers a way to instantiate more VMs with the guest OS of choice at the cost of me needing to refactor my website code so it can run in the straight jacket form factor dictated by the cloud vendor. Let's not kid ourselves here: most of us developers will never build a website which needs a truck load of VMs to run it: almost all websites created by developers can run on just a few VMs at most. Yet, the most expensive change is right at the start: moving from one to two VMs. As soon as you have refactored your website code to run across multiple VMs, adding another one is just as easy as clicking a mouse button. But that first step, that's the problem here and as it's right there at the beginning of scaling the website, it's particularly strange that cloud vendors refuse to solve that problem and leave it to the developers to solve that. Which makes migrating 'to the cloud' particularly expensive.

    Read the article

  • How do I set up MVP for a Winforms solution?

    - by JonWillis
    Question moved from Stackoverflow - http://stackoverflow.com/questions/4971048/how-do-i-set-up-mvp-for-a-winforms-solution I have used MVP and MVC in the past, and I prefer MVP as it controls the flow of execution so much better in my opinion. I have created my infrastructure (datastore/repository classes) and use them without issue when hard coding sample data, so now I am moving onto the GUI and preparing my MVP. Section A I have seen MVP using the view as the entry point, that is in the views constructor method it creates the presenter, which in turn creates the model, wiring up events as needed. I have also seen the presenter as the entry point, where a view, model and presenter are created, this presenter is then given a view and model object in its constructor to wire up the events. As in 2, but the model is not passed to the presenter. Instead the model is a static class where methods are called and responses returned directly. Section B In terms of keeping the view and model in sync I have seen. Whenever a value in the view in changed, i.e. TextChanged event in .Net/C#. This fires a DataChangedEvent which is passed through into the model, to keep it in sync at all times. And where the model changes, i.e. a background event it listens to, then the view is updated via the same idea of raising a DataChangedEvent. When a user wants to commit changes a SaveEvent it fires, passing through into the model to make the save. In this case the model mimics the view's data and processes actions. Similar to #b1, however the view does not sync with the model all the time. Instead when the user wants to commit changes, SaveEvent is fired and the presenter grabs the latest details and passes them into the model. in this case the model does not know about the views data until it is required to act upon it, in which case it is passed all the needed details. Section C Displaying of business objects in the view, i.e. a object (MyClass) not primitive data (int, double) The view has property fields for all its data that it will display as domain/business objects. Such as view.Animals exposes a IEnumerable<IAnimal> property, even though the view processes these into Nodes in a TreeView. Then for the selected animal it would expose SelectedAnimal as IAnimal property. The view has no knowledge of domain objects, it exposes property for primitive/framework (.Net/Java) included objects types only. In this instance the presenter will pass an adapter object the domain object, the adapter will then translate a given business object into the controls visible on the view. In this instance the adapter must have access to the actual controls on the view, not just any view so becomes more tightly coupled. Section D Multiple views used to create a single control. i.e. You have a complex view with a simple model like saving objects of different types. You could have a menu system at the side with each click on an item the appropriate controls are shown. You create one huge view, that contains all of the individual controls which are exposed via the views interface. You have several views. You have one view for the menu and a blank panel. This view creates the other views required but does not display them (visible = false), this view also implements the interface for each view it contains (i.e. child views) so it can expose to one presenter. The blank panel is filled with other views (Controls.Add(myview)) and ((myview.visible = true). The events raised in these "child"-views are handled by the parent view which in turn pass the event to the presenter, and visa versa for supplying events back down to child elements. Each view, be it the main parent or smaller child views are each wired into there own presenter and model. You can literately just drop a view control into an existing form and it will have the functionality ready, just needs wiring into a presenter behind the scenes. Section E Should everything have an interface, now based on how the MVP is done in the above examples will affect this answer as they might not be cross-compatible. Everything has an interface, the View, Presenter and Model. Each of these then obviously has a concrete implementation. Even if you only have one concrete view, model and presenter. The View and Model have an interface. This allows the views and models to differ. The presenter creates/is given view and model objects and it just serves to pass messages between them. Only the View has an interface. The Model has static methods and is not created, thus no need for an interface. If you want a different model, the presenter calls a different set of static class methods. Being static the Model has no link to the presenter. Personal thoughts From all the different variations I have presented (most I have probably used in some form) of which I am sure there are more. I prefer A3 as keeping business logic reusable outside just MVP, B2 for less data duplication and less events being fired. C1 for not adding in another class, sure it puts a small amount of non unit testable logic into a view (how a domain object is visualised) but this could be code reviewed, or simply viewed in the application. If the logic was complex I would agree to an adapter class but not in all cases. For section D, i feel D1 creates a view that is too big atleast for a menu example. I have used D2 and D3 before. Problem with D2 is you end up having to write lots of code to route events to and from the presenter to the correct child view, and its not drag/drop compatible, each new control needs more wiring in to support the single presenter. D3 is my prefered choice but adds in yet more classes as presenters and models to deal with the view, even if the view happens to be very simple or has no need to be reused. i think a mixture of D2 and D3 is best based on circumstances. As to section E, I think everything having an interface could be overkill I already do it for domain/business objects and often see no advantage in the "design" by doing so, but it does help in mocking objects in tests. Personally I would see E2 as a classic solution, although have seen E3 used in 2 projects I have worked on previously. Question Am I implementing MVP correctly? Is there a right way of going about it? I've read Martin Fowler's work that has variations, and I remember when I first started doing MVC, I understood the concept, but could not originally work out where is the entry point, everything has its own function but what controls and creates the original set of MVC objects.

    Read the article

  • June 2013 Release of the Ajax Control Toolkit

    - by Stephen.Walther
    I’m happy to announce the June 2013 release of the Ajax Control Toolkit. For this release, we enhanced the AjaxFileUpload control to support uploading files directly to Windows Azure. We also improved the SlideShow control by adding support for CSS3 animations. You can get the latest release of the Ajax Control Toolkit by visiting the project page at CodePlex (http://AjaxControlToolkit.CodePlex.com). Alternatively, you can execute the following NuGet command from the Visual Studio Library Package Manager window: Uploading Files to Azure The AjaxFileUpload control enables you to efficiently upload large files and display progress while uploading. With this release, we’ve added support for uploading large files directly to Windows Azure Blob Storage (You can continue to upload to your server hard drive if you prefer). Imagine, for example, that you have created an Azure Blob Storage container named pictures. In that case, you can use the following AjaxFileUpload control to upload to the container: <toolkit:ToolkitScriptManager runat="server" /> <toolkit:AjaxFileUpload ID="AjaxFileUpload1" StoreToAzure="true" AzureContainerName="pictures" runat="server" /> Notice that the AjaxFileUpload control is declared with two properties related to Azure. The StoreToAzure property causes the AjaxFileUpload control to upload a file to Azure instead of the local computer. The AzureContainerName property points to the blob container where the file is uploaded. .int3{position:absolute;clip:rect(487px,auto,auto,444px);}SMALL cash advance VERY CHEAP To use the AjaxFileUpload control, you need to modify your web.config file so it contains some additional settings. You need to configure the AjaxFileUpload handler and you need to point your Windows Azure connection string to your Blob Storage account. <configuration> <appSettings> <!--<add key="AjaxFileUploadAzureConnectionString" value="UseDevelopmentStorage=true"/>--> <add key="AjaxFileUploadAzureConnectionString" value="DefaultEndpointsProtocol=https;AccountName=testact;AccountKey=RvqL89Iw4npvPlAAtpOIPzrinHkhkb6rtRZmD0+ojZupUWuuAVJRyyF/LIVzzkoN38I4LSr8qvvl68sZtA152A=="/> </appSettings> <system.web> <compilation debug="true" targetFramework="4.5" /> <httpRuntime targetFramework="4.5" /> <httpHandlers> <add verb="*" path="AjaxFileUploadHandler.axd" type="AjaxControlToolkit.AjaxFileUploadHandler, AjaxControlToolkit"/> </httpHandlers> </system.web> <system.webServer> <validation validateIntegratedModeConfiguration="false" /> <handlers> <add name="AjaxFileUploadHandler" verb="*" path="AjaxFileUploadHandler.axd" type="AjaxControlToolkit.AjaxFileUploadHandler, AjaxControlToolkit"/> </handlers> <security> <requestFiltering> <requestLimits maxAllowedContentLength="4294967295"/> </requestFiltering> </security> </system.webServer> </configuration> You supply the connection string for your Azure Blob Storage account with the AjaxFileUploadAzureConnectionString property. If you set the value “UseDevelopmentStorage=true” then the AjaxFileUpload will upload to the simulated Blob Storage on your local machine. After you create the necessary configuration settings, you can use the AjaxFileUpload control to upload files directly to Azure (even very large files). Here’s a screen capture of how the AjaxFileUpload control appears in Google Chrome: After the files are uploaded, you can view the uploaded files in the Windows Azure Portal. You can see that all 5 files were uploaded successfully: New AjaxFileUpload Events In response to user feedback, we added two new events to the AjaxFileUpload control (on both the server and the client): · UploadStart – Raised on the server before any files have been uploaded. · UploadCompleteAll – Raised on the server when all files have been uploaded. · OnClientUploadStart – The name of a function on the client which is called before any files have been uploaded. · OnClientUploadCompleteAll – The name of a function on the client which is called after all files have been uploaded. These new events are most useful when uploading multiple files at a time. The updated AjaxFileUpload sample page demonstrates how to use these events to show the total amount of time required to upload multiple files (see the AjaxFileUpload.aspx file in the Ajax Control Toolkit sample site). SlideShow Animated Slide Transitions With this release of the Ajax Control Toolkit, we also added support for CSS3 animations to the SlideShow control. The animation is used when transitioning from one slide to another. Here’s the complete list of animations: · FadeInFadeOut · ScaleX · ScaleY · ZoomInOut · Rotate · SlideLeft · SlideDown You specify the animation which you want to use by setting the SlideShowAnimationType property. For example, here is how you would use the Rotate animation when displaying a set of slides: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="ShowSlideShow.aspx.cs" Inherits="TestACTJune2013.ShowSlideShow" %> <%@ Register TagPrefix="toolkit" Namespace="AjaxControlToolkit" Assembly="AjaxControlToolkit" %> <script runat="Server" type="text/C#"> [System.Web.Services.WebMethod] [System.Web.Script.Services.ScriptMethod] public static AjaxControlToolkit.Slide[] GetSlides() { return new AjaxControlToolkit.Slide[] { new AjaxControlToolkit.Slide("slides/Blue hills.jpg", "Blue Hills", "Go Blue"), new AjaxControlToolkit.Slide("slides/Sunset.jpg", "Sunset", "Setting sun"), new AjaxControlToolkit.Slide("slides/Winter.jpg", "Winter", "Wintery..."), new AjaxControlToolkit.Slide("slides/Water lilies.jpg", "Water lillies", "Lillies in the water"), new AjaxControlToolkit.Slide("slides/VerticalPicture.jpg", "Sedona", "Portrait style picture") }; } </script> <!DOCTYPE html> <html > <head runat="server"> <title></title> </head> <body> <form id="form1" runat="server"> <div> <toolkit:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server" /> <asp:Image ID="Image1" Height="300" Runat="server" /> <toolkit:SlideShowExtender ID="SlideShowExtender1" TargetControlID="Image1" SlideShowServiceMethod="GetSlides" AutoPlay="true" Loop="true" SlideShowAnimationType="Rotate" runat="server" /> </div> </form> </body> </html> In the code above, the set of slides is exposed by a page method named GetSlides(). The SlideShowAnimationType property is set to the value Rotate. The following animated GIF gives you an idea of the resulting slideshow: If you want to use either the SlideDown or SlideRight animations, then you must supply both an explicit width and height for the Image control which is the target of the SlideShow extender. For example, here is how you would declare an Image and SlideShow control to use a SlideRight animation: <toolkit:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server" /> <asp:Image ID="Image1" Height="300" Width="300" Runat="server" /> <toolkit:SlideShowExtender ID="SlideShowExtender1" TargetControlID="Image1" SlideShowServiceMethod="GetSlides" AutoPlay="true" Loop="true" SlideShowAnimationType="SlideRight" runat="server" /> Notice that the Image control includes both a Height and Width property. Here’s an approximation of this animation using an animated GIF: Summary The Superexpert team worked hard on this release. We hope you like the new improvements to both the AjaxFileUpload and the SlideShow controls. We’d love to hear your feedback in the comments. On to the next sprint!

    Read the article

  • Windows Azure Myths

    - by BuckWoody
    Windows Azure is part of the Microsoft "stack" - the suite of software and services we offer. Because we have so many products in almost every part of technology, it's hard to know everything about all parts of what we do - even for those of us who work here. So it's no surprise that some folks are not as familiar with Windows and SQL Azure as they are, say Windows Server or XBox. As I chat with folks about a solution for a business or organization need, I put Windows Azure into the mix. I always start off with "What do you already know about Windows Azure?" so that I don't bore folks with information they already have. I some cases they've checked out the product ahead of time and have specific questions, in others they aren't as familiar, and in still others there is a fair amount of mis-information. Sometimes that's because of a marketing failure, sometimes it's hearsay, and somtetimes it's active misinformation. I thought I might lay out a few of these misconceptions. As always - do your fact-checking! Never take anyone's word alone (including mine) as gospel. Make sure you educate yourself on your options. Your company or your clients depend on you to have the right information on IT, so make sure you live up to that. Myth 1: Nobody uses Windows Azure It's true that we don't give out numbers on the amount of clients on Windows and SQL Azure. But lots of folks are here - companies you may have heard of like Boeing, NASA, Fujitsu, The City of London, Nuedesic, and many others. I deal with firms small and large that use Windows Azure for mission-critical applications, sometimes totally on Windows and/or SQL Azure, sometimes in conjunction with an on-premises system, sometimes for only a specific component in Windows Azure like storage. The interesting thing is that many sites you visit have a Windows Azure component, or are running on Windows Azure. They just don't announce it. Just like the other cloud providers, the companies have asked to be completely branded themselves - they don't want you to be aware or care that they are on Windows Azure. Sometimes that's for security, other times it's for different reasons. It's just like the web sites you visit. For the most part, they don't advertise which OS or Web Server they use. It really just shouldn't matter. The point is that they just use what works to solve a given problem. Check out a few public case studies here: https://www.windowsazure.com/en-us/home/case-studies/ Myth 2: It's only for Microsoft stuff - can't use Open Source This is the one I face the most, and am the most dismayed by. We work just fine with many open source products, including Java, NodeJS, PHP, Ruby, Python, Hadoop, and many other languages and applications. You can quickly deploy a Wordpress, Umbraco and other "kits". We have software development kits (SDK's) for iPhones, iPads, Android, Windows phones and more. We have an SDK to work with FaceBook and other social networks. In short, we play well with others. More on the languages and runtimes we support here: https://www.windowsazure.com/en-us/develop/overview/ More on the SDK's here: http://www.wadewegner.com/2011/05/windows-azure-toolkit-for-ios/, http://www.wadewegner.com/2011/08/windows-azure-toolkits-for-devices-now-with-android/, http://azuretoolkit.codeplex.com/ Myth 3: Microsoft expects me to switch everything to "the cloud" No, we don't. That would be disasterous, unless the only things you run in your company uses works perfectly in Azure. Use Windows Azure  - or any cloud for that matter - where it works. Whenever I talk to companies, I focus on two things: Something that is broken and needs to be re-architected Something you want to do that is new If something is broken, and you need new tools to scale, extend, add capacity dynamically and so on, then you can consider using Windows or SQL Azure. It can help solve problems that you have, or it may include a component you don't want to write or architect yourself. Sometimes you want to do something new, like extend your company's offerings to mobile phones, to the web, or to a social network. More info on where it works here: http://blogs.msdn.com/b/buckwoody/archive/2011/01/18/windows-azure-and-sql-azure-use-cases.aspx Myth 4: I have to write code to use Windows and SQL Azure If Windows Azure is a PaaS - a Platform as a Service - then don't you have to write code to use it? Nope. Windows and SQL Azure are made up of various components. Some of those components allow you to write and deploy code (like Compute) and others don't. We have lots of customers using Windows Azure storage as a backup, to securely share files instead of using DropBox, to distribute videos or code or firmware, and more. Others use our High Performance Computing (HPC) offering to rent a supercomputer when they need one. You can even throw workloads at that using Excel! In addition there are lots of other components in Windows Azure you can use, from the Windows Azure Media Services to others. More here: https://www.windowsazure.com/en-us/home/scenarios/saas/ Myth 5: Windows Azure is just another form of "vendor lock-in" Windows Azure uses .NET, OSS languages and standard interfaces for the code. Sure, you're not going to take the code line-for-line and run it on a mainframe, but it's standard code that you write, and can port to something else. And the data is yours - you can bring it back whever you want. It's either in text or binary form, that you have complete control over. There are no licenses - you can "pay as you go", and when you're done, you can leave the service and take all your code, data and IP with you.   So go out there, read up, try it. Use it where it works. And don't believe everything you hear - sometimes the Internet doesn't get it all correct. :)

    Read the article

  • C#: LINQ vs foreach - Round 1.

    - by James Michael Hare
    So I was reading Peter Kellner's blog entry on Resharper 5.0 and its LINQ refactoring and thought that was very cool.  But that raised a point I had always been curious about in my head -- which is a better choice: manual foreach loops or LINQ?    The answer is not really clear-cut.  There are two sides to any code cost arguments: performance and maintainability.  The first of these is obvious and quantifiable.  Given any two pieces of code that perform the same function, you can run them side-by-side and see which piece of code performs better.   Unfortunately, this is not always a good measure.  Well written assembly language outperforms well written C++ code, but you lose a lot in maintainability which creates a big techncial debt load that is hard to offset as the application ages.  In contrast, higher level constructs make the code more brief and easier to understand, hence reducing technical cost.   Now, obviously in this case we're not talking two separate languages, we're comparing doing something manually in the language versus using a higher-order set of IEnumerable extensions that are in the System.Linq library.   Well, before we discuss any further, let's look at some sample code and the numbers.  First, let's take a look at the for loop and the LINQ expression.  This is just a simple find comparison:       // find implemented via LINQ     public static bool FindViaLinq(IEnumerable<int> list, int target)     {         return list.Any(item => item == target);     }         // find implemented via standard iteration     public static bool FindViaIteration(IEnumerable<int> list, int target)     {         foreach (var i in list)         {             if (i == target)             {                 return true;             }         }           return false;     }   Okay, looking at this from a maintainability point of view, the Linq expression is definitely more concise (8 lines down to 1) and is very readable in intention.  You don't have to actually analyze the behavior of the loop to determine what it's doing.   So let's take a look at performance metrics from 100,000 iterations of these methods on a List<int> of varying sizes filled with random data.  For this test, we fill a target array with 100,000 random integers and then run the exact same pseudo-random targets through both searches.                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     Any         10       26          0.00046             30.00%     Iteration   10       20          0.00023             -     Any         100      116         0.00201             18.37%     Iteration   100      98          0.00118             -     Any         1000     1058        0.01853             16.78%     Iteration   1000     906         0.01155             -     Any         10,000   10,383      0.18189             17.41%     Iteration   10,000   8843        0.11362             -     Any         100,000  104,004     1.8297              18.27%     Iteration   100,000  87,941      1.13163             -   The LINQ expression is running about 17% slower for average size collections and worse for smaller collections.  Presumably, this is due to the overhead of the state machine used to track the iterators for the yield returns in the LINQ expressions, which seems about right in a tight loop such as this.   So what about other LINQ expressions?  After all, Any() is one of the more trivial ones.  I decided to try the TakeWhile() algorithm using a Count() to get the position stopped like the sample Pete was using in his blog that Resharper refactored for him into LINQ:       // Linq form     public static int GetTargetPosition1(IEnumerable<int> list, int target)     {         return list.TakeWhile(item => item != target).Count();     }       // traditionally iterative form     public static int GetTargetPosition2(IEnumerable<int> list, int target)     {         int count = 0;           foreach (var i in list)         {             if(i == target)             {                 break;             }               ++count;         }           return count;     }   Once again, the LINQ expression is much shorter, easier to read, and should be easier to maintain over time, reducing the cost of technical debt.  So I ran these through the same test data:                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile   10       41          0.00041             128%     Iteration   10       18          0.00018             -     TakeWhile   100      171         0.00171             88%     Iteration   100      91          0.00091             -     TakeWhile   1000     1604        0.01604             94%     Iteration   1000     825         0.00825             -     TakeWhile   10,000   15765       0.15765             92%     Iteration   10,000   8204        0.08204             -     TakeWhile   100,000  156950      1.5695              92%     Iteration   100,000  81635       0.81635             -     Wow!  I expected some overhead due to the state machines iterators produce, but 90% slower?  That seems a little heavy to me.  So then I thought, well, what if TakeWhile() is not the right tool for the job?  The problem is TakeWhile returns each item for processing using yield return, whereas our for-loop really doesn't care about the item beyond using it as a stop condition to evaluate. So what if that back and forth with the iterator state machine is the problem?  Well, we can quickly create an (albeit ugly) lambda that uses the Any() along with a count in a closure (if a LINQ guru knows a better way PLEASE let me know!), after all , this is more consistent with what we're trying to do, we're trying to find the first occurence of an item and halt once we find it, we just happen to be counting on the way.  This mostly matches Any().       // a new method that uses linq but evaluates the count in a closure.     public static int TakeWhileViaLinq2(IEnumerable<int> list, int target)     {         int count = 0;         list.Any(item =>             {                 if(item == target)                 {                     return true;                 }                   ++count;                 return false;             });         return count;     }     Now how does this one compare?                         List<T> On 100,000 Iterations     Method         Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile      10       41          0.00041             128%     Any w/Closure  10       23          0.00023             28%     Iteration      10       18          0.00018             -     TakeWhile      100      171         0.00171             88%     Any w/Closure  100      116         0.00116             27%     Iteration      100      91          0.00091             -     TakeWhile      1000     1604        0.01604             94%     Any w/Closure  1000     1101        0.01101             33%     Iteration      1000     825         0.00825             -     TakeWhile      10,000   15765       0.15765             92%     Any w/Closure  10,000   10802       0.10802             32%     Iteration      10,000   8204        0.08204             -     TakeWhile      100,000  156950      1.5695              92%     Any w/Closure  100,000  108378      1.08378             33%     Iteration      100,000  81635       0.81635             -     Much better!  It seems that the overhead of TakeAny() returning each item and updating the state in the state machine is drastically reduced by using Any() since Any() iterates forward until it finds the value we're looking for -- for the task we're attempting to do.   So the lesson there is, make sure when you use a LINQ expression you're choosing the best expression for the job, because if you're doing more work than you really need, you'll have a slower algorithm.  But this is true of any choice of algorithm or collection in general.     Even with the Any() with the count in the closure it is still about 30% slower, but let's consider that angle carefully.  For a list of 100,000 items, it was the difference between 1.01 ms and 0.82 ms roughly in a List<T>.  That's really not that bad at all in the grand scheme of things.  Even running at 90% slower with TakeWhile(), for the vast majority of my projects, an extra millisecond to save potential errors in the long term and improve maintainability is a small price to pay.  And if your typical list is 1000 items or less we're talking only microseconds worth of difference.   It's like they say: 90% of your performance bottlenecks are in 2% of your code, so over-optimizing almost never pays off.  So personally, I'll take the LINQ expression wherever I can because they will be easier to read and maintain (thus reducing technical debt) and I can rely on Microsoft's development to have coded and unit tested those algorithm fully for me instead of relying on a developer to code the loop logic correctly.   If something's 90% slower, yes, it's worth keeping in mind, but it's really not until you start get magnitudes-of-order slower (10x, 100x, 1000x) that alarm bells should really go off.  And if I ever do need that last millisecond of performance?  Well then I'll optimize JUST THAT problem spot.  To me it's worth it for the readability, speed-to-market, and maintainability.

    Read the article

  • Windows Azure Myths

    - by BuckWoody
    Windows Azure is part of the Microsoft "stack" - the suite of software and services we offer. Because we have so many products in almost every part of technology, it's hard to know everything about all parts of what we do - even for those of us who work here. So it's no surprise that some folks are not as familiar with Windows and SQL Azure as they are, say Windows Server or XBox. As I chat with folks about a solution for a business or organization need, I put Windows Azure into the mix. I always start off with "What do you already know about Windows Azure?" so that I don't bore folks with information they already have. I some cases they've checked out the product ahead of time and have specific questions, in others they aren't as familiar, and in still others there is a fair amount of mis-information. Sometimes that's because of a marketing failure, sometimes it's hearsay, and somtetimes it's active misinformation. I thought I might lay out a few of these misconceptions. As always - do your fact-checking! Never take anyone's word alone (including mine) as gospel. Make sure you educate yourself on your options. Your company or your clients depend on you to have the right information on IT, so make sure you live up to that. Myth 1: Nobody uses Windows Azure It's true that we don't give out numbers on the amount of clients on Windows and SQL Azure. But lots of folks are here - companies you may have heard of like Boeing, NASA, Fujitsu, The City of London, Nuedesic, and many others. I deal with firms small and large that use Windows Azure for mission-critical applications, sometimes totally on Windows and/or SQL Azure, sometimes in conjunction with an on-premises system, sometimes for only a specific component in Windows Azure like storage. The interesting thing is that many sites you visit have a Windows Azure component, or are running on Windows Azure. They just don't announce it. Just like the other cloud providers, the companies have asked to be completely branded themselves - they don't want you to be aware or care that they are on Windows Azure. Sometimes that's for security, other times it's for different reasons. It's just like the web sites you visit. For the most part, they don't advertise which OS or Web Server they use. It really just shouldn't matter. The point is that they just use what works to solve a given problem. Check out a few public case studies here: https://www.windowsazure.com/en-us/home/case-studies/ Myth 2: It's only for Microsoft stuff - can't use Open Source This is the one I face the most, and am the most dismayed by. We work just fine with many open source products, including Java, NodeJS, PHP, Ruby, Python, Hadoop, and many other languages and applications. You can quickly deploy a Wordpress, Umbraco and other "kits". We have software development kits (SDK's) for iPhones, iPads, Android, Windows phones and more. We have an SDK to work with FaceBook and other social networks. In short, we play well with others. More on the languages and runtimes we support here: https://www.windowsazure.com/en-us/develop/overview/ More on the SDK's here: http://www.wadewegner.com/2011/05/windows-azure-toolkit-for-ios/, http://www.wadewegner.com/2011/08/windows-azure-toolkits-for-devices-now-with-android/, http://azuretoolkit.codeplex.com/ Myth 3: Microsoft expects me to switch everything to "the cloud" No, we don't. That would be disasterous, unless the only things you run in your company uses works perfectly in Azure. Use Windows Azure  - or any cloud for that matter - where it works. Whenever I talk to companies, I focus on two things: Something that is broken and needs to be re-architected Something you want to do that is new If something is broken, and you need new tools to scale, extend, add capacity dynamically and so on, then you can consider using Windows or SQL Azure. It can help solve problems that you have, or it may include a component you don't want to write or architect yourself. Sometimes you want to do something new, like extend your company's offerings to mobile phones, to the web, or to a social network. More info on where it works here: http://blogs.msdn.com/b/buckwoody/archive/2011/01/18/windows-azure-and-sql-azure-use-cases.aspx Myth 4: I have to write code to use Windows and SQL Azure If Windows Azure is a PaaS - a Platform as a Service - then don't you have to write code to use it? Nope. Windows and SQL Azure are made up of various components. Some of those components allow you to write and deploy code (like Compute) and others don't. We have lots of customers using Windows Azure storage as a backup, to securely share files instead of using DropBox, to distribute videos or code or firmware, and more. Others use our High Performance Computing (HPC) offering to rent a supercomputer when they need one. You can even throw workloads at that using Excel! In addition there are lots of other components in Windows Azure you can use, from the Windows Azure Media Services to others. More here: https://www.windowsazure.com/en-us/home/scenarios/saas/ Myth 5: Windows Azure is just another form of "vendor lock-in" Windows Azure uses .NET, OSS languages and standard interfaces for the code. Sure, you're not going to take the code line-for-line and run it on a mainframe, but it's standard code that you write, and can port to something else. And the data is yours - you can bring it back whever you want. It's either in text or binary form, that you have complete control over. There are no licenses - you can "pay as you go", and when you're done, you can leave the service and take all your code, data and IP with you.   So go out there, read up, try it. Use it where it works. And don't believe everything you hear - sometimes the Internet doesn't get it all correct. :)

    Read the article

  • Client side code snipets

    - by raghu.yadav
    function clientMethodCall(event) { component = event.getSource(); AdfCustomEvent.queue(component, "customEvent",{payload:component.getSubmittedValue()}, true); event.cancel(); } ]]-- <af:document>      <f:facet name="metaContainer">      <af:group>        <!--[CDATA[            <script>                function clientMethodCall(event) {                                       component = event.getSource();                    AdfCustomEvent.queue(component, "customEvent",{payload:component.getSubmittedValue()}, true);                                                     event.cancel();                                    }                 </script> ]]-->      </af:group>    </f:facet>      <af:form>        <af:panelformlayout>          <f:facet name="footer">          <af:inputtext label="Let me spy on you: Please enter your mail password">            <af:clientlistener method="clientMethodCall" type="keyUp">            <af:serverlistener type="customEvent" method="#{customBean.handleRequest}">          </af:serverlistener>bean code    public void handleRequest(ClientEvent event){                System.out.println("---"+event.getParameters().get("payload"));            } tree<af:tree id="tree1" value="#{bindings.DepartmentsView11.treeModel}" var="node" selectionlistener="#{bindings.DepartmentsView11.treeModel.makeCurrent}" rowselection="single">    <f:facet name="nodeStamp">      <af:outputtext value="#{node}">    </af:outputtext>    <af:clientlistener method="expandNode" type="selection">  </af:clientlistener></f:facet>   <f:facet name="metaContainer">        <af:group>          <!--[CDATA[            <script>                function expandNode(event){                    var _tree = event.getSource();                    rwKeySet = event.getAddedSet();                    var firstRowKey;                    for(rowKey in rwKeySet){                       firstRowKey  = rowKey;                        // we are interested in the first hit, so break out here                        break;                    }                    if (_tree.isPathExpanded(firstRowKey)){                         _tree.setDisclosedRowKey(firstRowKey,false);                    }                    else{                        _tree.setDisclosedRowKey(firstRowKey,true);                    }               }        </script> ]]-->        </af:group>      </f:facet>   </af:tree> </af:clientlistener></af:inputtext></f:facet></af:panelformlayout></af:form></af:document> bean code public void handleRequest(ClientEvent event){ System.out.println("---"+event.getParameters().get("payload")); } tree function expandNode(event){ var _tree = event.getSource(); rwKeySet = event.getAddedSet(); var firstRowKey; for(rowKey in rwKeySet){ firstRowKey = rowKey; // we are interested in the first hit, so break out here break; } if (_tree.isPathExpanded(firstRowKey)){ _tree.setDisclosedRowKey(firstRowKey,false); } else{ _tree.setDisclosedRowKey(firstRowKey,true); } } ]]--

    Read the article

  • Integrating Coherence & Java EE 6 Applications using ActiveCache

    - by Ricardo Ferreira
    OK, so you are a developer and are starting a new Java EE 6 application using the most wonderful features of the Java EE platform like Enterprise JavaBeans, JavaServer Faces, CDI, JPA e another cool stuff technologies. And your architecture need to hold piece of data into distributed caches to improve application's performance, scalability and reliability? If this is your current facing scenario, maybe you should look closely in the solutions provided by Oracle WebLogic Server. Oracle had integrated WebLogic Server and its champion data caching technology called Oracle Coherence. This seamless integration between this two products provides a comprehensive environment to develop applications without the complexity of extra Java code to manage cache as a dependency, since Oracle provides an DI ("Dependency Injection") mechanism for Coherence, the same DI mechanism available in standard Java EE applications. This feature is called ActiveCache. In this article, I will show you how to configure ActiveCache in WebLogic and at your Java EE application. Configuring WebLogic to manage Coherence Before you start changing your application to use Coherence, you need to configure your Coherence distributed cache. The good news is, you can manage all this stuff without writing a single line of code of XML or even Java. This configuration can be done entirely in the WebLogic administration console. The first thing to do is the setup of a Coherence cluster. A Coherence cluster is a set of Coherence JVMs configured to form one single view of the cache. This means that you can insert or remove members of the cluster without the client application (the application that generates or consume data from the cache) knows about the changes. This concept allows your solution to scale-out without changing the application server JVMs. You can growth your application only in the data grid layer. To start the configuration, you need to configure an machine that points to the server in which you want to execute the Coherence JVMs. WebLogic Server allows you to do this very easily using the Administration Console. In this example, I will call the machine as "coherence-server". Remember that in order to the machine concept works, you need to ensure that the NodeManager are being executed in the target server that the machine points to. The NodeManager executable can be found in <WLS_HOME>/server/bin/startNodeManager.sh. The next thing to do is to configure a Coherence cluster. In the WebLogic administration console, go to Environment > Coherence Clusters and click in "New". Call this Coherence cluster of "my-coherence-cluster". Click in next. Specify a valid cluster address and port. The Coherence members will communicate with each other through this address and port. Our Coherence cluster are now configured. Now it is time to configure the Coherence members and add them to this cluster. In the WebLogic administration console, go to Environment > Coherence Servers and click in "New". In the field "Name" set to "coh-server-1". In the field "Machine", associate this Coherence server to the machine "coherence-server". In the field "Cluster", associate this Coherence server to the cluster named "my-coherence-cluster". Click in "Finish". Start the Coherence server using the "Control" tab of WebLogic administration console. This will instruct WebLogic to start a new JVM of Coherence in the target machine that should join the pre-defined Coherence cluster. Configuring your Java EE Application to Access Coherence Now lets pass to the funny part of the configuration. The first thing to do is to inform your Java EE application which Coherence cluster to join. Oracle had updated WebLogic server deployment descriptors so you will not have to change your code or the containers deployment descriptors like application.xml, ejb-jar.xml or web.xml. In this example, I will show you how to enable DI ("Dependency Injection") to a Coherence cache from a Servlet 3.0 component. In the WEB-INF/weblogic.xml deployment descriptor, put the following metadata information: <?xml version="1.0" encoding="UTF-8"?> <wls:weblogic-web-app xmlns:wls="http://xmlns.oracle.com/weblogic/weblogic-web-app" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd http://xmlns.oracle.com/weblogic/weblogic-web-app http://xmlns.oracle.com/weblogic/weblogic-web-app/1.4/weblogic-web-app.xsd"> <wls:context-root>myWebApp</wls:context-root> <wls:coherence-cluster-ref> <wls:coherence-cluster-name>my-coherence-cluster</wls:coherence-cluster-name> </wls:coherence-cluster-ref> </wls:weblogic-web-app> As you can see, using the "coherence-cluster-name" tag, we are informing our Java EE application that it should join the "my-coherence-cluster" when it loads in the web container. Without this information, the application will not be able to access the predefined Coherence cluster. It will form its own Coherence cluster without any members. So never forget to put this information. Now put the coherence.jar and active-cache-1.0.jar dependencies at your WEB-INF/lib application classpath. You need to deploy this dependencies so ActiveCache can automatically take care of the Coherence cluster join phase. This dependencies can be found in the following locations: - <WLS_HOME>/common/deployable-libraries/active-cache-1.0.jar - <COHERENCE_HOME>/lib/coherence.jar Finally, you need to write down the access code to the Coherence cache at your Servlet. In the following example, we have a Servlet 3.0 component that access a Coherence cache named "transactions" and prints into the browser output the content (the ammount property) of one specific transaction. package com.oracle.coherence.demo.activecache; import java.io.IOException; import javax.annotation.Resource; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.tangosol.net.NamedCache; @WebServlet("/demo/specificTransaction") public class TransactionServletExample extends HttpServlet { @Resource(mappedName = "transactions") NamedCache transactions; protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { int transId = Integer.parseInt(request.getParameter("transId")); Transaction transaction = (Transaction) transactions.get(transId); response.getWriter().println("<center>" + transaction.getAmmount() + "</center>"); } } Thats it! No more configuration is necessary and you have all set to start producing and getting data to/from Coherence. As you can see in the example code, the Coherence cache are treated as a normal dependency in the Java EE container. The magic happens behind the scenes when the ActiveCache allows your application to join the defined Coherence cluster. The most interesting thing about this approach is, no matter which type of Coherence cache your are using (Distributed, Partitioned, Replicated, WAN-Remote) for the client application, it is just a simple attribute member of com.tangosol.net.NamedCache type. And its all managed by the Java EE container as an dependency. This means that if you inject the same dependency (the Coherence cache named "transactions") in another Java EE component (JSF managed-bean, Stateless EJB) the cache will be the same. Cool isn't it? Thanks to the CDI technology, we can extend the same support for non-Java EE standards components like simple POJOs. This means that you are not forced to only use Servlets, EJBs or JSF in order to inject Coherence caches. You can do the same approach for regular POJOs created for you and managed by lightweight containers like Spring or Seam.

    Read the article

  • SQL SERVER – Core Concepts – Elasticity, Scalability and ACID Properties – Exploring NuoDB an Elastically Scalable Database System

    - by pinaldave
    I have been recently exploring Elasticity and Scalability attributes of databases. You can see that in my earlier blog posts about NuoDB where I wanted to look at Elasticity and Scalability concepts. The concepts are very interesting, and intriguing as well. I have discussed these concepts with my friend Joyti M and together we have come up with this interesting read. The goal of this article is to answer following simple questions What is Elasticity? What is Scalability? How ACID properties vary from NOSQL Concepts? What are the prevailing problems in the current database system architectures? Why is NuoDB  an innovative and welcome change in database paradigm? Elasticity This word’s original form is used in many different ways and honestly it does do a decent job in holding things together over the years as a person grows and contracts. Within the tech world, and specifically related to software systems (database, application servers), it has come to mean a few things - allow stretching of resources without reaching the breaking point (on demand). What are resources in this context? Resources are the usual suspects – RAM/CPU/IO/Bandwidth in the form of a container (a process or bunch of processes combined as modules). When it is about increasing resources the simplest idea which comes to mind is the addition of another container. Another container means adding a brand new physical node. When it is about adding a new node there are two questions which comes to mind. 1) Can we add another node to our software system? 2) If yes, does adding new node cause downtime for the system? Let us assume we have added new node, let us see what the new needs of the system are when a new node is added. Balancing incoming requests to multiple nodes Synchronization of a shared state across multiple nodes Identification of “downstate” and resolution action to bring it to “upstate” Well, adding a new node has its advantages as well. Here are few of the positive points Throughput can increase nearly horizontally across the node throughout the system Response times of application will increase as in-between layer interactions will be improved Now, Let us put the above concepts in the perspective of a Database. When we mention the term “running out of resources” or “application is bound to resources” the resources can be CPU, Memory or Bandwidth. The regular approach to “gain scalability” in the database is to look around for bottlenecks and increase the bottlenecked resource. When we have memory as a bottleneck we look at the data buffers, locks, query plans or indexes. After a point even this is not enough as there needs to be an efficient way of managing such large workload on a “single machine” across memory and CPU bound (right kind of scheduling)  workload. We next move on to either read/write separation of the workload or functionality-based sharing so that we still have control of the individual. But this requires lots of planning and change in client systems in terms of knowing where to go/update/read and for reporting applications to “aggregate the data” in an intelligent way. What we ideally need is an intelligent layer which allows us to do these things without us getting into managing, monitoring and distributing the workload. Scalability In the context of database/applications, scalability means three main things Ability to handle normal loads without pressure E.g. X users at the Y utilization of resources (CPU, Memory, Bandwidth) on the Z kind of hardware (4 processor, 32 GB machine with 15000 RPM SATA drives and 1 GHz Network switch) with T throughput Ability to scale up to expected peak load which is greater than normal load with acceptable response times Ability to provide acceptable response times across the system E.g. Response time in S milliseconds (or agreed upon unit of measure) – 90% of the time The Issue – Need of Scale In normal cases one can plan for the load testing to test out normal, peak, and stress scenarios to ensure specific hardware meets the needs. With help from Hardware and Software partners and best practices, bottlenecks can be identified and requisite resources added to the system. Unfortunately this vertical scale is expensive and difficult to achieve and most of the operational people need the ability to scale horizontally. This helps in getting better throughput as there are physical limits in terms of adding resources (Memory, CPU, Bandwidth and Storage) indefinitely. Today we have different options to achieve scalability: Read & Write Separation The idea here is to do actual writes to one store and configure slaves receiving the latest data with acceptable delays. Slaves can be used for balancing out reads. We can also explore functional separation or sharing as well. We can separate data operations by a specific identifier (e.g. region, year, month) and consolidate it for reporting purposes. For functional separation the major disadvantage is when schema changes or workload pattern changes. As the requirement grows one still needs to deal with scale need in manual ways by providing an abstraction in the middle tier code. Using NOSQL solutions The idea is to flatten out the structures in general to keep all values which are retrieved together at the same store and provide flexible schema. The issue with the stores is that they are compromising on mostly consistency (no ACID guarantees) and one has to use NON-SQL dialect to work with the store. The other major issue is about education with NOSQL solutions. Would one really want to make these compromises on the ability to connect and retrieve in simple SQL manner and learn other skill sets? Or for that matter give up on ACID guarantee and start dealing with consistency issues? Hybrid Deployment – Mac, Linux, Cloud, and Windows One of the challenges today that we see across On-premise vs Cloud infrastructure is a difference in abilities. Take for example SQL Azure – it is wonderful in its concepts of throttling (as it is shared deployment) of resources and ability to scale using federation. However, the same abilities are not available on premise. This is not a mistake, mind you – but a compromise of the sweet spot of workloads, customer requirements and operational SLAs which can be supported by the team. In today’s world it is imperative that databases are available across operating systems – which are a commodity and used by developers of all hues. An Ideal Database Ability List A system which allows a linear scale of the system (increase in throughput with reasonable response time) with the addition of resources A system which does not compromise on the ACID guarantees and require developers to learn new paradigms A system which does not force fit a new way interacting with database by learning Non-SQL dialect A system which does not force fit its mechanisms for providing availability across its various modules. Well NuoDB is the first database which has all of the above abilities and much more. In future articles I will cover my hands-on experience with it. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: NuoDB

    Read the article

  • Anatomy of a .NET Assembly - Custom attribute encoding

    - by Simon Cooper
    In my previous post, I covered how field, method, and other types of signatures are encoded in a .NET assembly. Custom attribute signatures differ quite a bit from these, which consequently affects attribute specifications in C#. Custom attribute specifications In C#, you can apply a custom attribute to a type or type member, specifying a constructor as well as the values of fields or properties on the attribute type: public class ExampleAttribute : Attribute { public ExampleAttribute(int ctorArg1, string ctorArg2) { ... } public Type ExampleType { get; set; } } [Example(5, "6", ExampleType = typeof(string))] public class C { ... } How does this specification actually get encoded and stored in an assembly? Specification blob values Custom attribute specification signatures use the same building blocks as other types of signatures; the ELEMENT_TYPE structure. However, they significantly differ from other types of signatures, in that the actual parameter values need to be stored along with type information. There are two types of specification arguments in a signature blob; fixed args and named args. Fixed args are the arguments to the attribute type constructor, named arguments are specified after the constructor arguments to provide a value to a field or property on the constructed attribute type (PropertyName = propValue) Values in an attribute blob are limited to one of the basic types (one of the number types, character, or boolean), a reference to a type, an enum (which, in .NET, has to use one of the integer types as a base representation), or arrays of any of those. Enums and the basic types are easy to store in a blob - you simply store the binary representation. Strings are stored starting with a compressed integer indicating the length of the string, followed by the UTF8 characters. Array values start with an integer indicating the number of elements in the array, then the item values concatentated together. Rather than using a coded token, Type values are stored using a string representing the type name and fully qualified assembly name (for example, MyNs.MyType, MyAssembly, Version=1.0.0.0, Culture=neutral, PublicKeyToken=0123456789abcdef). If the type is in the current assembly or mscorlib then just the type name can be used. This is probably done to prevent direct references between assemblies solely because of attribute specification arguments; assemblies can be loaded in the reflection-only context and attribute arguments still processed, without loading the entire assembly. Fixed and named arguments Each entry in the CustomAttribute metadata table contains a reference to the object the attribute is applied to, the attribute constructor, and the specification blob. The number and type of arguments to the constructor (the fixed args) can be worked out by the method signature referenced by the attribute constructor, and so the fixed args can simply be concatenated together in the blob without any extra type information. Named args are different. These specify the value to assign to a field or property once the attribute type has been constructed. In the CLR, fields and properties can be overloaded just on their type; different fields and properties can have the same name. Therefore, to uniquely identify a field or property you need: Whether it's a field or property (indicated using byte values 0x53 and 0x54, respectively) The field or property type The field or property name After the fixed arg values is a 2-byte number specifying the number of named args in the blob. Each named argument has the above information concatenated together, mostly using the basic ELEMENT_TYPE values, in the same way as a method or field signature. A Type argument is represented using the byte 0x50, and an enum argument is represented using the byte 0x55 followed by a string specifying the name and assembly of the enum type. The named argument property information is followed by the argument value, using the same encoding as fixed args. Boxed objects This would be all very well, were it not for object and object[]. Arguments and properties of type object allow a value of any allowed argument type to be specified. As a result, more information needs to be specified in the blob to interpret the argument bytes as the correct type. So, the argument value is simple prepended with the type of the value by specifying the ELEMENT_TYPE or name of the enum the value represents. For named arguments, a field or property of type object is represented using the byte 0x51, with the actual type specified in the argument value. Some examples... All property signatures start with the 2-byte value 0x0001. Similar to my previous post in the series, names in capitals correspond to a particular byte value in the ELEMENT_TYPE structure. For strings, I'll simply give the string value, rather than the length and UTF8 encoding in the actual blob. I'll be using the following enum and attribute types to demonstrate specification encodings: class AttrAttribute : Attribute { public AttrAttribute() {} public AttrAttribute(Type[] tArray) {} public AttrAttribute(object o) {} public AttrAttribute(MyEnum e) {} public AttrAttribute(ushort x, int y) {} public AttrAttribute(string str, Type type1, Type type2) {} public int Prop1 { get; set; } public object Prop2 { get; set; } public object[] ObjectArray; } enum MyEnum : int { Val1 = 1, Val2 = 2 } Now, some examples: Here, the the specification binds to the (ushort, int) attribute constructor, with fixed args only. The specification blob starts off with a prolog, followed by the two constructor arguments, then the number of named arguments (zero): [Attr(42, 84)] 0x0001 0x002a 0x00000054 0x0000 An example of string and type encoding: [Attr("MyString", typeof(Array), typeof(System.Windows.Forms.Form))] 0x0001 "MyString" "System.Array" "System.Windows.Forms.Form, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" 0x0000 As you can see, the full assembly specification of a type is only needed if the type isn't in the current assembly or mscorlib. Note, however, that the C# compiler currently chooses to fully-qualify mscorlib types anyway. An object argument (this binds to the object attribute constructor), and two named arguments (a null string is represented by 0xff and the empty string by 0x00) [Attr((ushort)40, Prop1 = 12, Prop2 = "")] 0x0001 U2 0x0028 0x0002 0x54 I4 "Prop1" 0x0000000c 0x54 0x51 "Prop2" STRING 0x00 Right, more complicated now. A type array as a fixed argument: [Attr(new[] { typeof(string), typeof(object) })] 0x0001 0x00000002 // the number of elements "System.String" "System.Object" 0x0000 An enum value, which is simply represented using the underlying value. The CLR works out that it's an enum using information in the attribute constructor signature: [Attr(MyEnum.Val1)] 0x0001 0x00000001 0x0000 And finally, a null array, and an object array as a named argument: [Attr((Type[])null, ObjectArray = new object[] { (byte)2, typeof(decimal), null, MyEnum.Val2 })] 0x0001 0xffffffff 0x0001 0x53 SZARRAY 0x51 "ObjectArray" 0x00000004 U1 0x02 0x50 "System.Decimal" STRING 0xff 0x55 "MyEnum" 0x00000002 As you'll notice, a null object is encoded as a null string value, and a null array is represented using a length of -1 (0xffffffff). How does this affect C#? So, we can now explain why the limits on attribute arguments are so strict in C#. Attribute specification blobs are limited to basic numbers, enums, types, and arrays. As you can see, this is because the raw CLR encoding can only accommodate those types. Special byte patterns have to be used to indicate object, string, Type, or enum values in named arguments; you can't specify an arbitary object type, as there isn't a generalised way of encoding the resulting value in the specification blob. In particular, decimal values can't be encoded, as it isn't a 'built-in' CLR type that has a native representation (you'll notice that decimal constants in C# programs are compiled as several integer arguments to DecimalConstantAttribute). Jagged arrays also aren't natively supported, although you can get around it by using an array as a value to an object argument: [Attr(new object[] { new object[] { new Type[] { typeof(string) } }, 42 })] Finally... Phew! That was a bit longer than I thought it would be. Custom attribute encodings are complicated! Hopefully this series has been an informative look at what exactly goes on inside a .NET assembly. In the next blog posts, I'll be carrying on with the 'Inside Red Gate' series.

    Read the article

  • Why Is Faulty Behaviour In The .NET Framework Not Fixed?

    - by Alois Kraus
    Here is the scenario: You have a Windows Form Application that calls a method via Invoke or BeginInvoke which throws exceptions. Now you want to find out where the error did occur and how the method has been called. Here is the output we do get when we call Begin/EndInvoke or simply Invoke The actual code that was executed was like this:         private void cInvoke_Click(object sender, EventArgs e)         {             InvokingFunction(CallMode.Invoke);         }            [MethodImpl(MethodImplOptions.NoInlining)]         void InvokingFunction(CallMode mode)         {             switch (mode)             {                 case CallMode.Invoke:                     this.Invoke(new MethodInvoker(GenerateError));   The faulting method is called GenerateError which does throw a NotImplementedException exception and wraps it in a NotSupportedException.           [MethodImpl(MethodImplOptions.NoInlining)]         void GenerateError()         {             F1();         }           private void F1()         {             try             {                 F2();             }             catch (Exception ex)             {                 throw new NotSupportedException("Outer Exception", ex);             }         }           private void F2()         {            throw new NotImplementedException("Inner Exception");         } It is clear that the method F2 and F1 did actually throw these exceptions but we do not see them in the call stack. If we directly call the InvokingFunction and catch and print the exception we can find out very easily how we did get into this situation. We see methods F1,F2,GenerateError and InvokingFunction directly in the stack trace and we see that actually two exceptions did occur. Here is for comparison what we get from Invoke/EndInvoke System.NotImplementedException: Inner Exception     StackTrace:    at System.Windows.Forms.Control.MarshaledInvoke(Control caller, Delegate method, Object[] args, Boolean synchronous)     at System.Windows.Forms.Control.Invoke(Delegate method, Object[] args)     at WindowsFormsApplication1.AppForm.InvokingFunction(CallMode mode)     at WindowsFormsApplication1.AppForm.cInvoke_Click(Object sender, EventArgs e)     at System.Windows.Forms.Control.OnClick(EventArgs e)     at System.Windows.Forms.Button.OnClick(EventArgs e) The exception message is kept but the stack starts running from our Invoke call and not from the faulting method F2. We have therefore no clue where this exception did occur! The stack starts running at the method MarshaledInvoke because the exception is rethrown with the throw catchedException which resets the stack trace. That is bad but things are even worse because if previously lets say 5 exceptions did occur .NET will return only the first (innermost) exception. That does mean that we do not only loose the original call stack but all other exceptions and all data contained therein as well. It is a pity that MS does know about this and simply closes this issue as not important. Programmers will play a lot more around with threads than before thanks to TPL, PLINQ that do come with .NET 4. Multithreading is hyped quit a lot in the press and everybody wants to use threads. But if the .NET Framework makes it nearly impossible to track down the easiest UI multithreading issue I have a problem with that. The problem has been reported but obviously not been solved. .NET 4 Beta 2 did not have changed that dreaded GetBaseException call in MarshaledInvoke to return only the innermost exception of the complete exception stack. It is really time to fix this. WPF on the other hand does the right thing and wraps the exceptions inside a TargetInvocationException which makes much more sense. But Not everybody uses WPF for its daily work and Windows forms applications will still be used for a long time. Below is the code to repro the issues shown and how the exceptions can be rendered in a meaningful way. The default Exception.ToString implementation generates a hard to interpret stack if several nested exceptions did occur. using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.Threading; using System.Globalization; using System.Runtime.CompilerServices;   namespace WindowsFormsApplication1 {     public partial class AppForm : Form     {         enum CallMode         {             Direct = 0,             BeginInvoke = 1,             Invoke = 2         };           public AppForm()         {             InitializeComponent();             Thread.CurrentThread.CurrentUICulture = CultureInfo.InvariantCulture;             Application.ThreadException += new System.Threading.ThreadExceptionEventHandler(Application_ThreadException);         }           void Application_ThreadException(object sender, System.Threading.ThreadExceptionEventArgs e)         {             cOutput.Text = PrintException(e.Exception, 0, null).ToString();         }           private void cDirectUnhandled_Click(object sender, EventArgs e)         {             InvokingFunction(CallMode.Direct);         }           private void cDirectCall_Click(object sender, EventArgs e)         {             try             {                 InvokingFunction(CallMode.Direct);             }             catch (Exception ex)             {                 cOutput.Text = PrintException(ex, 0, null).ToString();             }         }           private void cInvoke_Click(object sender, EventArgs e)         {             InvokingFunction(CallMode.Invoke);         }           private void cBeginInvokeCall_Click(object sender, EventArgs e)         {             InvokingFunction(CallMode.BeginInvoke);         }           [MethodImpl(MethodImplOptions.NoInlining)]         void InvokingFunction(CallMode mode)         {             switch (mode)             {                 case CallMode.Direct:                     GenerateError();                     break;                 case CallMode.Invoke:                     this.Invoke(new MethodInvoker(GenerateError));                     break;                 case CallMode.BeginInvoke:                     IAsyncResult res = this.BeginInvoke(new MethodInvoker(GenerateError));                     this.EndInvoke(res);                     break;             }         }           [MethodImpl(MethodImplOptions.NoInlining)]         void GenerateError()         {             F1();         }           private void F1()         {             try             {                 F2();             }             catch (Exception ex)             {                 throw new NotSupportedException("Outer Exception", ex);             }         }           private void F2()         {            throw new NotImplementedException("Inner Exception");         }           StringBuilder PrintException(Exception ex, int identLevel, StringBuilder sb)         {             StringBuilder builtStr = sb;             if( builtStr == null )                 builtStr = new StringBuilder();               if( ex == null )                 return builtStr;                 WriteLine(builtStr, String.Format("{0}: {1}", ex.GetType().FullName, ex.Message), identLevel);             WriteLine(builtStr, String.Format("StackTrace: {0}", ShortenStack(ex.StackTrace)), identLevel + 1);             builtStr.AppendLine();               return PrintException(ex.InnerException, ++identLevel, builtStr);         }               void WriteLine(StringBuilder sb, string msg, int identLevel)         {             foreach (string trimmedLine in SplitToLines(msg)                                            .Select( (line) => line.Trim()) )             {                 for (int i = 0; i < identLevel; i++)                     sb.Append('\t');                 sb.Append(trimmedLine);                 sb.AppendLine();             }         }           string ShortenStack(string stack)         {             int nonAppFrames = 0;             // Skip stack frames not part of our app but include two foreign frames and skip the rest             // If our stack frame is encountered reset counter to 0             return SplitToLines(stack)                               .Where((line) =>                               {                                   nonAppFrames = line.Contains("WindowsFormsApplication1") ? 0 : nonAppFrames + 1;                                   return nonAppFrames < 3;                               })                              .Select((line) => line)                              .Aggregate("", (current, line) => current + line + Environment.NewLine);         }           static char[] NewLines = Environment.NewLine.ToCharArray();         string[] SplitToLines(string str)         {             return str.Split(NewLines, StringSplitOptions.RemoveEmptyEntries);         }     } }

    Read the article

  • Building dynamic OLAP data marts on-the-fly

    - by DrJohn
    At the forthcoming SQLBits conference, I will be presenting a session on how to dynamically build an OLAP data mart on-the-fly. This blog entry is intended to clarify exactly what I mean by an OLAP data mart, why you may need to build them on-the-fly and finally outline the steps needed to build them dynamically. In subsequent blog entries, I will present exactly how to implement some of the techniques involved. What is an OLAP data mart? In data warehousing parlance, a data mart is a subset of the overall corporate data provided to business users to meet specific business needs. Of course, the term does not specify the technology involved, so I coined the term "OLAP data mart" to identify a subset of data which is delivered in the form of an OLAP cube which may be accompanied by the relational database upon which it was built. To clarify, the relational database is specifically create and loaded with the subset of data and then the OLAP cube is built and processed to make the data available to the end-users via standard OLAP client tools. Why build OLAP data marts? Market research companies sell data to their clients to make money. To gain competitive advantage, market research providers like to "add value" to their data by providing systems that enhance analytics, thereby allowing clients to make best use of the data. As such, OLAP cubes have become a standard way of delivering added value to clients. They can be built on-the-fly to hold specific data sets and meet particular needs and then hosted on a secure intranet site for remote access, or shipped to clients' own infrastructure for hosting. Even better, they support a wide range of different tools for analytical purposes, including the ever popular Microsoft Excel. Extension Attributes: The Challenge One of the key challenges in building multiple OLAP data marts based on the same 'template' is handling extension attributes. These are attributes that meet the client's specific reporting needs, but do not form part of the standard template. Now clearly, these extension attributes have to come into the system via additional files and ultimately be added to relational tables so they can end up in the OLAP cube. However, processing these files and filling dynamically altered tables with SSIS is a challenge as SSIS packages tend to break as soon as the database schema changes. There are two approaches to this: (1) dynamically build an SSIS package in memory to match the new database schema using C#, or (2) have the extension attributes provided as name/value pairs so the file's schema does not change and can easily be loaded using SSIS. The problem with the first approach is the complexity of writing an awful lot of complex C# code. The problem of the second approach is that name/value pairs are useless to an OLAP cube; so they have to be pivoted back into a proper relational table somewhere in the data load process WITHOUT breaking SSIS. How this can be done will be part of future blog entry. What is involved in building an OLAP data mart? There are a great many steps involved in building OLAP data marts on-the-fly. The key point is that all the steps must be automated to allow for the production of multiple OLAP data marts per day (i.e. many thousands, each with its own specific data set and attributes). Now most of these steps have a great deal in common with standard data warehouse practices. The key difference is that the databases are all built to order. The only permanent database is the metadata database (shown in orange) which holds all the metadata needed to build everything else (i.e. client orders, configuration information, connection strings, client specific requirements and attributes etc.). The staging database (shown in red) has a short life: it is built, populated and then ripped down as soon as the OLAP Data Mart has been populated. In the diagram below, the OLAP data mart comprises the two blue components: the Data Mart which is a relational database and the OLAP Cube which is an OLAP database implemented using Microsoft Analysis Services (SSAS). The client may receive just the OLAP cube or both components together depending on their reporting requirements.  So, in broad terms the steps required to fulfil a client order are as follows: Step 1: Prepare metadata Create a set of database names unique to the client's order Modify all package connection strings to be used by SSIS to point to new databases and file locations. Step 2: Create relational databases Create the staging and data mart relational databases using dynamic SQL and set the database recovery mode to SIMPLE as we do not need the overhead of logging anything Execute SQL scripts to build all database objects (tables, views, functions and stored procedures) in the two databases Step 3: Load staging database Use SSIS to load all data files into the staging database in a parallel operation Load extension files containing name/value pairs. These will provide client-specific attributes in the OLAP cube. Step 4: Load data mart relational database Load the data from staging into the data mart relational database, again in parallel where possible Allocate surrogate keys and use SSIS to perform surrogate key lookup during the load of fact tables Step 5: Load extension tables & attributes Pivot the extension attributes from their native name/value pairs into proper relational tables Add the extension attributes to the views used by OLAP cube Step 6: Deploy & Process OLAP cube Deploy the OLAP database directly to the server using a C# script task in SSIS Modify the connection string used by the OLAP cube to point to the data mart relational database Modify the cube structure to add the extension attributes to both the data source view and the relevant dimensions Remove any standard attributes that not required Process the OLAP cube Step 7: Backup and drop databases Drop staging database as it is no longer required Backup data mart relational and OLAP database and ship these to the client's infrastructure Drop data mart relational and OLAP database from the build server Mark order complete Start processing the next order, ad infinitum. So my future blog posts and my forthcoming session at the SQLBits conference will all focus on some of the more interesting aspects of building OLAP data marts on-the-fly such as handling the load of extension attributes and how to dynamically alter the structure of an OLAP cube using C#.

    Read the article

< Previous Page | 443 444 445 446 447 448 449 450 451 452 453 454  | Next Page >