Search Results

Search found 17526 results on 702 pages for 'dynamic methods'.

Page 267/702 | < Previous Page | 263 264 265 266 267 268 269 270 271 272 273 274  | Next Page >

  • Introdução ao NHibernate on TechDays 2010

    - by Ricardo Peres
    I’ve been working on the agenda for my presentation titled Introdução ao NHibernate that I’ll be giving on TechDays 2010, and I would like to request your assistance. If you have any subject that you’d like me to talk about, you can suggest it to me. For now, I’m thinking of the following issues: Domain Driven Design with NHibernate Inheritance Mapping Strategies (Table Per Class Hierarchy, Table Per Type, Table Per Concrete Type, Mixed) Mappings (hbm.xml, NHibernate Attributes, Fluent NHibernate, ConfORM) Supported querying types (ID, HQL, LINQ, Criteria API, QueryOver, SQL) Entity Relationships Custom Types Caching Interceptors and Listeners Advanced Usage (Duck Typing, EntityMode Map, …) Other projects (NHibernate Validator, NHibernate Search, NHibernate Shards, …) ASP.NET Integration ASP.NET Dynamic Data Integration WCF Data Services Integration Comments?

    Read the article

  • OBIEE 11g 11.1.1.7.1 is Available For BI Enterprise

    - by p.anda
    (in via Ian) The Business Intelligence Enterprise Edition (OBIEE) 11.1.1.7.1 patch set has been released.  This patch set is available for all customers who are using Oracle Business Intelligence Enterprise Edition 11.1.1.7.0. Now available to download from My Oracle Support Patch 16556157: OBIEE BUNDLE PATCH 11.1.1.7.1 This single OBIEE 11.1.1.7.1 patch set download is comprised of the following: 1 of 6 Oracle Business Intelligence Installer (BIINST) 2 of 6 Oracle Business Intelligence Publisher (BIP) 3 of 6 EPM Components Installed from BI Installer 11.1.1.7.0 (BIFNDNEPM)) 4 of 6 Oracle Business Intelligence Server (BIS) 5 of 6 Oracle Business Intelligence Presentation Services (BIPS) 6 of 6 Oracle Business Intelligence Platform Client Installers and MapViewer Ensure to review the readme file on the Installer download for important installation instructions The following is also required to be downloaded and applied: Patch 16569379: Dynamic Monitoring Service patch Additional important notes are available in  the following document: Document 1566124.1: OBIEE 11g 11.1.1.7.1 is Available for Oracle Business Intelligence Enterprise Edition

    Read the article

  • Slideshows in elastic or fluid layouts?

    - by aendrew
    Hi folks, I'm building a new WordPress TwentyTen child theme using the ElastiCSS framework ( http://elasticss.com/ ) and am trying to figure out the best way of using some sort of dynamic content slideshow. What is the best way to implement a slideshow in a fluid or elastic layout such that it remains proportional to the other items in the content area? Should I even bother trying to obtain that? Or should I use like four different sizes in conjunction with something like the Less framework ( http://lessframework.com/ )? Thanks! (BTW, I've posted here because this was more of a "what's the best option" question than a "How do I program that?" question. If you think it would be more appropriate on SO, please move it there.)

    Read the article

  • Using DLLEXPORT to export DLL function With Class to C#

    - by SICGames2013
    In my previous revision game engine I deported major functions for the game editor for C#. Now, I'm beginning to revise the game engine with a static library. There's a already dynamic library created in C++ to use DLLEXPORT for C#. Just now I want to test out the newer functions and created a DLL file from C++. Because the DLL contains classes I was wondering how would I be able to use DLL Export. Would I do this: [DLLEXPORT("GameEngine.dll", EntryPoint="SomeClass", Conventional=_stdcall)] static extern void functionFromClass(); I have a feeling it's probably DLLImport and not DLLExport. I was wondering how would I go about this? Another way I was thinking was because I already have the DLL in C++ prepared already to go the C# Class Library. I could just keep the new engine as a lib, and link the lib with the old DLL C++ file. Wouldn't the EntryPoint be able to point to the class the function is in?

    Read the article

  • How to use call web service action in SharePoint2013 workflow

    - by ybbest
    In SharePoint2013, you can use call web service action and loop. In this post, I will show you how to achieve this. 1. Create a List workflow called CallWebService 2. Create a variable called listurl and assign the value to http://sp2010/_vti_bin/listdata.svc 3. Create a dictionary variable called RequestHeaders and add the following key value pairs. 4. Call the web service with the HttpHeaders you just build in the previous step and store the response in the variable ResponseContent. 5. The ResponseContent variable is the Dynamic values (in SharePoint designer it will be called dictionary type) and it is new feature for SharePoint2013 workflow. We can use the following actions to count the number items in the variable. 6. You can use loop in SharePoint 2013 workflow and out each list title as shown below.

    Read the article

  • Sales & Operations Planning in the Cloud (Value Chain Planning) with JD Edwards

    - by Hartmut Wiese
    AVATA, a US based Oracle Partner with the EMEA Headquarter in Germany is offering a pre-integrated, cloud based integration with JD Edwards. It is a Sales & Operations Planning hub that enables companies to seamlessly plan across the entire organization via a dynamic, continuous and collaborative web-based Sales and Operations Planning process. There is a datasheet uploaded to the EMEA JD Edwards Partner Community workspace here which explains options and benefits and has contact details included as well. You need to be a member of this Community to access the workspace. Please register here.

    Read the article

  • Date Compare Validator Control ASP.NET

    - by Sahanr
    Compare two input dates to avoid invalid dates. In this example I have created two textboxes and namded as "TextBoxSeminarDate" and "TextBoxBookingDeadline". Booking deadline date must be before date to the Seminar date. Therefore I used Operator as "LesThanEqual". I have validated "TextBoxBookingDeadline" value comparing with the "TextBoxSeminarDate" value as follow.   <asp:CompareValidator ID="CompareValidatorBookingDeadline" runat="server" ControlToCompare="TextBoxSeminarDate" ControlToValidate="TextBoxBookingDeadline" Display="Dynamic" ErrorMessage="Please check the seminar date and select appropriate date for booking deadline" Operator="LessThanEqual" Type="Date"  ValueToCompare="<%= TextBoxSeminarDate.Text.ToShortString() %>">*</asp:CompareValidator> The important thing is "ValueToCompare" property of the compare validator. Here I have assined it to the value of the TextboxSeminarDate and then compered it with the booking deadline date.  

    Read the article

  • Internet Good but update manager not good

    - by Raja
    I am using Ubuntu 12.04 . I am doing Internet with a USB Modem of 236kbps . My issue is , If i am accessing webpage through browser its good but if i am doing sudo apt-get update through terminal , its not responding & its just hanging there .I am unable to get whats my issue . help me to solve this . one more thing , i am unable to change my dns also . raja@badfox:~$ cat /etc/resolv.conf # Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8) # DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN nameserver 220.226.100.40 nameserver 220.226.6.104 nameserver 127.0.0.1 I wanna replace them to dns ip's linked here http://www.cyberciti.biz/faq/free-dns-server/ see the picture to have some idea about my issue .

    Read the article

  • Drawing simple geometric figures with DrawUserPrimitives?

    - by Navy Seal
    I'm trying to draw a simple triangle based on an array of vertex. I've been searching for a tutorial and I found a simple example on riemers but I couldn't get it to work. I think it was made for XNA 3 and it seems there were some changes to XNA 4? Using this example: http://www.riemers.net/eng/Tutorials/XNA/Csharp/Series1/The_first_triangle.php I get this error: Additional information: The current vertex declaration does not include all the elements required by the current vertex shader. TextureCoordinate0 is missing. I'm not english so I'm having some trouble to understand everything. For what I understand error is confusing because I'm trying to draw a triangle color based and not texture based and it shouldn't need a texture. Also I saw some articles about dynamic shadows and lights and I would like to know if this is the kind of code used to do it with some tweaks like culling because I'm wondering if its heavy code for performance in real time.

    Read the article

  • Automatically create bug resolution task using the TFS 2010 API

    - by Bob Hardister
    My customer requires bug resolution to be approved and tracked.  To minimize the overhead for developers I implemented a TFS 2010 server-side plug-in to automatically create a child resolution task for the bug when the “CCB” field is set to approved. The CCB field is a custom field.  I also added the story points field to the bug WIT for sizing purposes. Redundant tasks will not be created unless the bug title is changed or the prior task is closed. The program writes an audit trail to a log file visible in the TFS Admin Console Log view. Here’s the code. BugAutoTask.cs /* SPECIFICATION * When the CCB field on the bug is set to approved, create a child task where the task: * name = Resolve bug [ID] - [Title of bug] * assigned to = same as assigned to field on the bug * same area path * same iteration path * activity = Bug Resolution * original estimate = bug points * * The source code is used to build a dll (Ows.TeamFoundation.BugAutoTaskCreation.PlugIns.dll), * which needs to be copied to * C:\Program Files\Microsoft Team Foundation Server 2010\Application Tier\Web Services\bin\Plugins * on ALL TFS application-tier servers. * * Author: Bob Hardister. */ using System; using System.Collections.Generic; using System.IO; using System.Xml; using System.Text; using System.Diagnostics; using System.Linq; using Microsoft.TeamFoundation.Common; using Microsoft.TeamFoundation.Framework.Server; using Microsoft.TeamFoundation.WorkItemTracking.Client; using Microsoft.TeamFoundation.WorkItemTracking.Server; using Microsoft.TeamFoundation.Client; using System.Collections; namespace BugAutoTaskCreation { public class BugAutoTask : ISubscriber { public EventNotificationStatus ProcessEvent(TeamFoundationRequestContext requestContext, NotificationType notificationType, object notificationEventArgs, out int statusCode, out string statusMessage, out ExceptionPropertyCollection properties) { statusCode = 0; properties = null; statusMessage = String.Empty; // Error message for for tracing last code executed and optional fields string lastStep = "No field values found or set "; try { if ((notificationType == NotificationType.Notification) && (notificationEventArgs.GetType() == typeof(WorkItemChangedEvent))) { WorkItemChangedEvent workItemChange = (WorkItemChangedEvent)notificationEventArgs; // see ConnectToTFS() method below to select which TFS instance/collection // to connect to TfsTeamProjectCollection tfs = ConnectToTFS(); WorkItemStore wiStore = tfs.GetService<WorkItemStore>(); lastStep = lastStep + ": connection to TFS successful "; // Get the work item that was just changed by the user. WorkItem witem = wiStore.GetWorkItem(workItemChange.CoreFields.IntegerFields[0].NewValue); lastStep = lastStep + ": retrieved changed work item, ID:" + witem.Id + " "; // Filter for Bug work items only if (witem.Type.Name == "Bug") { // DEBUG lastStep = lastStep + ": changed work item is a bug "; // Filter for CCB (i.e. Baseline Status) field set to approved only bool BaselineStatusChange = false; if (workItemChange.ChangedFields != null) { ProcessBugRevision(ref lastStep, workItemChange, wiStore, ref witem, ref BaselineStatusChange); } } } } catch (Exception e) { Trace.WriteLine(e.Message); Logger log = new Logger(); log.WriteLineToLog(MsgLevel.Error, "Application error: " + lastStep + " - " + e.Message + " - " + e.InnerException); } statusCode = 1; statusMessage = "Bug Auto Task Evaluation Completed"; properties = null; return EventNotificationStatus.ActionApproved; } // PRIVATE METHODS private static void ProcessBugRevision(ref string lastStep, WorkItemChangedEvent workItemChange, WorkItemStore wiStore, ref WorkItem witem, ref bool BaselineStatusChange) { foreach (StringField field in workItemChange.ChangedFields.StringFields) { // DEBUG lastStep = lastStep + ": last changed field is - " + field.Name + " "; if (field.Name == "Baseline Status") { lastStep = lastStep + ": retrieved bug baseline status field value, bug ID:" + witem.Id + " "; BaselineStatusChange = (field.NewValue != field.OldValue); if ((BaselineStatusChange) && (field.NewValue == "Approved")) { // Instanciate logger Logger log = new Logger(); // *** Create resolution task for this bug *** // ******************************************* // Get the team project and selected field values of the bug work item Project teamProject = witem.Project; int bugID = witem.Id; string bugTitle = witem.Fields["System.Title"].Value.ToString(); string bugAssignedTo = witem.Fields["System.AssignedTo"].Value.ToString(); string bugAreaPath = witem.Fields["System.AreaPath"].Value.ToString(); string bugIterationPath = witem.Fields["System.IterationPath"].Value.ToString(); string bugChangedBy = witem.Fields["System.ChangedBy"].OriginalValue.ToString(); string bugTeamProject = witem.Project.Name; lastStep = lastStep + ": all mandatory bug field values found "; // Optional fields Field bugPoints = witem.Fields["Microsoft.VSTS.Scheduling.StoryPoints"]; if (bugPoints.Value != null) { lastStep = lastStep + ": all mandatory and optional bug field values found "; } // Initialize child resolution task title string childTaskTitle = "Resolve bug " + bugID + " - " + bugTitle; // At this point I can check if a resolution task (of the same name) // for the bug already exist // If so, do not create a new resolution task bool createResolutionTask = true; WorkItem parentBug = wiStore.GetWorkItem(bugID); WorkItemLinkCollection links = parentBug.WorkItemLinks; foreach (WorkItemLink wil in links) { if (wil.LinkTypeEnd.Name == "Child") { WorkItem childTask = wiStore.GetWorkItem(wil.TargetId); if ((childTask.Title == childTaskTitle) && (childTask.State != "Closed")) { createResolutionTask = false; log.WriteLineToLog(MsgLevel.Info, "Team project " + bugTeamProject + ": " + bugChangedBy + " - set the CCB field to \"Approved\" for bug, ID: " + bugID + ". Task not created as open one of the same name already exist, ID:" + childTask.Id); } } } if (createResolutionTask) { // Define the work item type of the new work item WorkItemTypeCollection workItemTypes = wiStore.Projects[teamProject.Name].WorkItemTypes; WorkItemType wiType = workItemTypes["Task"]; // Setup the new task and assign field values witem = new WorkItem(wiType); witem.Fields["System.Title"].Value = "Resolve bug " + bugID + " - " + bugTitle; witem.Fields["System.AssignedTo"].Value = bugAssignedTo; witem.Fields["System.AreaPath"].Value = bugAreaPath; witem.Fields["System.IterationPath"].Value = bugIterationPath; witem.Fields["Microsoft.VSTS.Common.Activity"].Value = "Bug Resolution"; lastStep = lastStep + ": all mandatory task field values set "; // Optional fields if (bugPoints.Value != null) { witem.Fields["Microsoft.VSTS.Scheduling.OriginalEstimate"].Value = bugPoints.Value; lastStep = lastStep + ": all mandatory and optional task field values set "; } // Check for validation errors before saving the new task and linking it to the bug ArrayList validationErrors = witem.Validate(); if (validationErrors.Count == 0) { witem.Save(); // Link the new task (child) to the bug (parent) var linkType = wiStore.WorkItemLinkTypes[CoreLinkTypeReferenceNames.Hierarchy]; // Fetch the work items to be linked var parentWorkItem = wiStore.GetWorkItem(bugID); int taskID = witem.Id; var childWorkItem = wiStore.GetWorkItem(taskID); // Add a new link to the parent relating the child and save it parentWorkItem.Links.Add(new WorkItemLink(linkType.ForwardEnd, childWorkItem.Id)); parentWorkItem.Save(); log.WriteLineToLog(MsgLevel.Info, "Team project " + bugTeamProject + ": " + bugChangedBy + " - set the CCB field to \"Approved\" for bug, ID:" + bugID + ", which automatically created child resolution task, ID:" + taskID); } else { log.WriteLineToLog(MsgLevel.Error, "Error in creating bug resolution child task for bug ID:" + bugID); foreach (Field taskField in validationErrors) { log.WriteLineToLog(MsgLevel.Error, " - Validation Error in task field: " + taskField.ReferenceName); } } } } } } } private TfsTeamProjectCollection ConnectToTFS() { // Connect to TFS string tfsUri = string.Empty; // Production TFS instance production collection tfsUri = @"xxxx"; // Production TFS instance admin collection //tfsUri = @"xxxxx"; // Local TFS testing instance default collection //tfsUri = @"xxxxx"; TfsTeamProjectCollection tfs = new TfsTeamProjectCollection(new System.Uri(tfsUri)); tfs.EnsureAuthenticated(); return tfs; } // HELPERS public string Name { get { return "Bug Auto Task Creation Event Handler"; } } public SubscriberPriority Priority { get { return SubscriberPriority.Normal; } } public enum MsgLevel { Info, Warning, Error }; public Type[] SubscribedTypes() { return new Type[1] { typeof(WorkItemChangedEvent) }; } } } Logger.cs using System; using System.Collections.Generic; using System.IO; using System.Linq; using System.Text; using System.Windows.Forms; namespace BugAutoTaskCreation { class Logger { // fields private string _ApplicationDirectory = @"C:\ProgramData\Microsoft\Team Foundation\Server Configuration\Logs"; private string _LogFileName = @"\CFG_ACCT_AT_OWS_BugAutoTaskCreation.log"; private string _LogFile; private string _LogTimestamp = DateTime.Now.ToString("MM/dd/yyyy HH:mm:ss"); private string _MsgLevelText = string.Empty; // default constructor public Logger() { // check for a prior log file FileInfo logFile = new FileInfo(_ApplicationDirectory + _LogFileName); if (!logFile.Exists) { CreateNewLogFile(ref logFile); } } // properties public string ApplicationDirectory { get { return _ApplicationDirectory; } set { _ApplicationDirectory = value; } } public string LogFile { get { _LogFile = _ApplicationDirectory + _LogFileName; return _LogFile; } set { _LogFile = value; } } // PUBLIC METHODS public void WriteLineToLog(BugAutoTask.MsgLevel msgLevel, string logRecord) { try { // set msgLevel text if (msgLevel == BugAutoTask.MsgLevel.Info) { _MsgLevelText = "[Info @" + MsgTimeStamp() + "] "; } else if (msgLevel == BugAutoTask.MsgLevel.Warning) { _MsgLevelText = "[Warning @" + MsgTimeStamp() + "] "; } else if (msgLevel == BugAutoTask.MsgLevel.Error) { _MsgLevelText = "[Error @" + MsgTimeStamp() + "] "; } else { _MsgLevelText = "[Error: unsupported message level @" + MsgTimeStamp() + "] "; } // write a line to the log file StreamWriter logFile = new StreamWriter(_ApplicationDirectory + _LogFileName, true); logFile.WriteLine(_MsgLevelText + logRecord); logFile.Close(); } catch (Exception) { throw; } } // PRIVATE METHODS private void CreateNewLogFile(ref FileInfo logFile) { try { string logFilePath = logFile.FullName; // write the log file header _MsgLevelText = "[Info @" + MsgTimeStamp() + "] "; string cpu = string.Empty; if (Environment.Is64BitOperatingSystem) { cpu = " (x64)"; } StreamWriter newLog = new StreamWriter(logFilePath, false); newLog.Flush(); newLog.WriteLine(_MsgLevelText + "===================================================================="); newLog.WriteLine(_MsgLevelText + "Team Foundation Server Administration Log"); newLog.WriteLine(_MsgLevelText + "Version : " + "1.0.0 Author: Bob Hardister"); newLog.WriteLine(_MsgLevelText + "DateTime : " + _LogTimestamp); newLog.WriteLine(_MsgLevelText + "Type : " + "OWS Custom TFS API Plug-in"); newLog.WriteLine(_MsgLevelText + "Activity : " + "Bug Auto Task Creation for CCB Approved Bugs"); newLog.WriteLine(_MsgLevelText + "Area : " + "Build Explorer"); newLog.WriteLine(_MsgLevelText + "Assembly : " + "Ows.TeamFoundation.BugAutoTaskCreation.PlugIns.dll"); newLog.WriteLine(_MsgLevelText + "Location : " + @"C:\Program Files\Microsoft Team Foundation Server 2010\Application Tier\Web Services\bin\Plugins"); newLog.WriteLine(_MsgLevelText + "User : " + Environment.UserDomainName + @"\" + Environment.UserName); newLog.WriteLine(_MsgLevelText + "Machine : " + Environment.MachineName); newLog.WriteLine(_MsgLevelText + "System : " + Environment.OSVersion + cpu); newLog.WriteLine(_MsgLevelText + "===================================================================="); newLog.WriteLine(_MsgLevelText); newLog.Close(); } catch (Exception) { throw; } } private string MsgTimeStamp() { string msgTimestamp = string.Empty; return msgTimestamp = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss:fff"); } } }

    Read the article

  • website not available outside

    - by Keshav Nair
    I am new to ubuntu server and i have installed ubuntu server on a vm and installed LAMP etc but my problem is that my website is not visible outside. i have port triggering and added port 21,22 and 80. i really don't know what am doing, i am totally lost! I have a dynamic ip but i can access the server through 192.168.25.1 no matter how many times i restart the modem and from my public ip. I get redirected to my router settings what should i do??

    Read the article

  • RightNow CX @ OpenWorld: What to Experience

    - by Tony Berk
    We want to welcome our RightNow CX customers to Oracle OpenWorld next week. Get ready for a great week and a whole new experience! For a high level overview of what is going on during the week, please review these previous posts: Is There a Cloud Over OpenWorld? and What to "CRM" in San Francisco? CRM Highlights for OpenWorld '12. Also, don't forget you can add on the Customer Experience Summit @ OpenWorld to make your week even more complete and get involved with the Experience Revolution! Below is a highlight of only some of the RightNow related sessions at OpenWorld. Please use OpenWorld Schedule Builder or check the OpenWorld Content Catalog for all of the session details and any time or location changes. Tip: Pre-enrolled session registrants via Schedule Builder are allowed into the session rooms before anyone else, so Schedule Builder will guarantee you a seat. Many of the sessions below will likely be at capacity. No better way to start off than hearing where Oracle RightNow is going! Oracle RightNow CX Cloud Service Vision and Roadmap (CON9764) - Oct 1, 10:45 AM. Oracle RightNow CX Cloud Service combines Web, social, and contact center experiences for a unified, cross-channel service solution in the cloud, enabling organizations to increase sales and adoption, build trust, strengthen relationships, and reduce costs and effort. Come to this session to hear from David Vap and his team of Oracle experts about where the product is going and how Oracle is committed to accelerating the pace of innovation and value to its customers. Interested in the Cloud and want to know why some leading CIOs are moving to the cloud? You can hear first hand from CIOs from Emerson, Intuit and Overstock.com: CIOs and Governance in the Cloud (CON9767) - Oct 3, 11:45 AM.   And of course there are a number of sessions that drill down into more specific areas. Here are just a few: Deliver Outstanding Customer Experiences: Oracle RightNow Dynamic Agent Desktop Cloud Service (CON9771) - Oct 1, 4:45 PM. This session covers how companies have delivered exceptional customer experiences and how the Oracle RightNow Dynamic Agent Desktop Cloud Service roadmap will evolve in the future. The Oracle RightNow Contact Center Experience suite includes incident management, knowledge, guided processes, and other service capabilities to unify the customer experience across channels. Come learn about the powerful tools that enable even your junior agents to consistently provide outstanding service across all customer interaction channels. Self-Service in the Age of Data Intimacy (CON11516) - Oct 1, 3:15. Even though businesses are generating more and more data around their relationships and interactions with customers, very little of the information a business generates ends up available to the contact center and even less is made available to the online service experience. The generic one-size-fits-all approach that typifies most online service experiences ultimately fails to address all user needs, and that failure ultimately leads to the continued use of high-cost agent-assisted channels for low-value interactions. This session introduces Oracle RightNow Web Experience’s Virtual Assistant and discusses how you can deliver rich, engaging, highly personalized experiences with the quality of agent-assisted service at a much lower cost. Improve Chat Experiences: Best Practices for Chat Pilots and Deployments (CON11517) - Oct 1, 4:45 PM. Today’s organizations are challenged to grow revenue and retain customers with fewer resources, and many have turned to chat as an approach to improving the customer experience, increasing sales conversions, and reducing costs at the same time. From setting goals and metrics and training staff to customizing and tuning the solution, this session provides best practices and lessons learned from a broad set of implementations to help you get the most out of your chat solution. Differentiated Experience with Web Service (CON9770) - Oct 2, 1:15 PM. A reputation for excellent customer service can differentiate your brand and drive revenue. In this session, learn how to develop that reputation by transforming your online self-service into a highly interactive, branded customer experience. See live examples of how Oracle RightNow Web Experience has helped customers deliver on their Web service strategies. Unifying the Agent’s Engagement Console (CON11518) - Oct 2, 1:15 PM. Does your customer experience suffer because your agents are toggling between multiple tools? Do your agent productivity and morale suffer as well? Come to this session to learn how Oracle RightNow CX Cloud Service seamlessly unifies these disparate systems into a single engagement console. Regardless of channel, powerful adaptive tools consistently guide agents across contextually aware personalized workflows. Great agent experiences drive great customer experiences. Oracle RightNow CX Cloud Service and the Oracle Customer Experience Portfolio (CON9775) - Oct 3, 10:15 AM. This session covers how Oracle’s integrated suite of customer experience (CX) products fits with the Oracle CX portfolio of products (Oracle Fusion Customer Relationship Management; the Oracle ATG, Oracle Endeca, and Oracle Knowledge product families; and Oracle Business Intelligence) to increase revenues, strengthen customer relationships, and reduce costs across the entire end-to-end customer lifecycle for companies that sell to consumers and those that sell to businesses. Greater Insights from Customer Engagements (CON9773) Oct 4, 12:45 PM. In this session, hear how to leverage service interaction insights, customer feedback, and segmented service engagements to improve the customer experience. Discover how customers, such as J&P Cycles, learn and take action based on business insights gained through their customer engagements. Again, these are just some of the sessions, so check out the Content Catalog for details on Knowledge Management, Customization, Integration and more in the Oracle Develop stream for Customer Experience. Be sure to visit the Oracle DEMOgrounds in the Moscone West Exhibit Hall. If this is your first OpenWorld, welcome! If you are returning, hi again and enjoy!

    Read the article

  • How can I host a website on a dynamically-assigned IP address?

    - by nick
    I recently upgraded my internet to the point that it is much faster and more reliable than my current webhost. I would like to move my current domain to be hosted at home, but my IP address is dynamic. As far as I know, I only get a new IP when I restart my modem and or router (which is almost never) or when cable one (my ISP) pushes out a firmware update (rarely). There are a few ways I can see doing this: Convince my ISP to give me a static IP Assign my router my current IP to force a static IP (which might work?) Set my DNS record to my current IP address and update it on the rare occasions that it changes. Obviously I'm hoping that the first one works, but I don't want to pay a lot of extra money (if that's what it takes) to get a static IP address. Which of these options will work most reliably?

    Read the article

  • What is the difference between Java 6 and PHP 5.4? [closed]

    - by Mashael
    First of all, let me explain the matter. I'm in a class where we learn Java 6 OOP fundamentals. However, my goal is to learn PHP (the last version) next. So, my question: Is there a big difference between PHP and Java 6 in OOP concepts? Meaning that after I finish the OOP class in Java will I find a lot of things that need to be learned in PHP regarding OOP? Update: *My goal of learning PHP next is to build dynamic sites* (I'm not sure of other options) and to follow OOP.

    Read the article

  • How does a search functionality fit in DDD with CQRS?

    - by Songo
    In Vaughn Vernon's book Implementing domain driven design and the accompanying sample application I found that he implemented a CQRS approach to the iddd_collaboration bounded context. He presents the following classes in the application service layer: CalendarApplicationService.java CalendarEntryApplicationService.java CalendarEntryQueryService.java CalendarQueryService.java I'm interested to know if an application will have a search page that feature numerous drop downs and check boxes with a smart text box to match different search patterns; How will you structure all that search logic? In a command service or a query service? Taking a look at the CalendarQueryService.java I can see that it has 2 methods for a huge query, but no logic at all to mix and match any search filters for example. I've heard that the application layer shouldn't have any business logic, so where will I construct my dynamic query? or maybe just clutter everything in the Query service?

    Read the article

  • Can not print after upgrading from 12.x to 14.04

    - by user318889
    After upgrading from V12.04 to V14.04 I am not able to print. I am using an HP LaserJet 400 M451dn. The printer troubleshooter told me that there is no solution to the problem. This is the output of the advanced diagnositc output. (Due to limited space I cut the output!) Can anybody tell me what is going wrong. I am using the printer via USB ? Page 1 (Scheduler not running?): {'cups_connection_failure': False} Page 2 (Is local server publishing?): {'local_server_exporting_printers': False} Page 3 (Choose printer): {'cups_dest': , 'cups_instance': None, 'cups_queue': u'HP-LaserJet-400-color-M451dn', 'cups_queue_listed': True} Page 4 (Check printer sanity): {'cups_device_uri_scheme': u'hp', 'cups_printer_dict': {'device-uri': u'hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670', 'printer-info': u'Hewlett-Packard HP LaserJet 400 color M451dn', 'printer-is-shared': True, 'printer-location': u'Pinatubo', 'printer-make-and-model': u'HP LJ 300-400 color M351-M451 Postscript (recommended)', 'printer-state': 4, 'printer-state-message': u'', 'printer-state-reasons': [u'none'], 'printer-type': 8556636, 'printer-uri-supported': u'ipp://localhost:631/printers/HP-LaserJet-400-color-M451dn'}, 'cups_printer_remote': False, 'hplip_output': (['', '\x1b[01mHP Linux Imaging and Printing System (ver. 3.14.6)\x1b[0m', '\x1b[01mDevice Information Utility ver. 5.2\x1b[0m', '', 'Copyright (c) 2001-13 Hewlett-Packard Development Company, LP', 'This software comes with ABSOLUTELY NO WARRANTY.', 'This is free software, and you are welcome to distribute it', 'under certain conditions. See COPYING file for more details.', '', '', '\x1b[01mhp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670\x1b[0m', '', '\x1b[01mDevice Parameters (dynamic data):\x1b[0m', '\x1b[01m Parameter Value(s) \x1b[0m', ' ---------------------------- ----------------------------------------------------------', ' back-end hp ', " cups-printers ['HP-LaserJet-400-color-M451dn'] ", ' cups-uri hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670 ', ' dev-file ', ' device-state -1 ', ' device-uri hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670 ', ' deviceid ', ' error-state 101 ', ' host ', ' is-hp True ', ' panel 0 ', ' panel-line1 ', ' panel-line2 ', ' port 1 ', ' serial CNFF308670 ', ' status-code 5002 ', ' status-desc ', '\x1b[01m', 'Model Parameters (static data):\x1b[0m', '\x1b[01m Parameter Value(s) \x1b[0m', ' ---------------------------- ----------------------------------------------------------', ' align-type 0 ', ' clean-type 0 ', ' color-cal-type 0 ', ' copy-type 0 ', ' embedded-server-type 0 ', ' fax-type 0 ', ' fw-download False ', ' icon hp_color_laserjet_cp2025.png ', ' io-mfp-mode 1 ', ' io-mode 1 ', ' io-support 6 ', ' job-storage 0 ', ' linefeed-cal-type 0 ', ' model HP_LaserJet_400_color_M451dn ', ' model-ui HP LaserJet 400 Color m451dn ', ' model1 HP LaserJet 400 Color M451dn ', ' monitor-type 0 ', ' panel-check-type 0 ', ' pcard-type 0 ', ' plugin 0 ', ' plugin-reason 0 ', ' power-settings 0 ', ' ppd-name lj_300_400_color_m351_m451 ', ' pq-diag-type 0 ', ' r-type 0 ', ' r0-agent1-kind 4 ', ' r0-agent1-sku CE410A/CE410X ', ' r0-agent1-type 1 ', ' r0-agent2-kind 4 ', ' r0-agent2-sku CE411A ', ' r0-agent2-type 4 ', ' r0-agent3-kind 4 ', ' r0-agent3-sku CE413A ', ' r0-agent3-type 5 ', ' r0-agent4-kind 4 ', ' r0-agent4-sku CE412A ', ' r0-agent4-type 6 ', ' scan-src 0 ', ' scan-type 0 ', ' status-battery-check 0 ', ' status-dynamic-counters 0 ', ' status-type 3 ', ' support-released True ', ' support-subtype 2202411 ', ' support-type 2 ', ' support-ver 3.12.2 ', " tech-class ['Postscript'] ", " tech-subclass ['Normal'] ", ' tech-type 4 ', ' usb-pid 3882 ', ' usb-vid 1008 ', ' wifi-config 0 ', '\x1b[01m', 'Status History (most recent first):\x1b[0m', '\x1b[01m Date/Time Code Status Description User Job ID \x1b[0m', ' -------------------- ----- ---------------------------------------- -------- --------', ' 08/21/14 00:07:25 5012 Device communication error richard 0 ', ' 08/20/14 13:42:44 500 Started a print job richard 4214 ', '', '', 'Done.', ''], ['\x1b[35;01mwarning: No display found.\x1b[0m', '\x1b[31;01merror: hp-info -u/--gui requires Qt4 GUI support. Entering interactive mode.\x1b[0m', '\x1b[31;01merror: Unable to communicate with device (code=12): hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670\x1b[0m', '\x1b[31;01merror: Error opening device (Device not found).\x1b[0m', ''], 0), 'is_cups_class': False, 'local_cups_queue_attributes': {'charset-configured': u'utf-8', 'charset-supported': [u'us-ascii', u'utf-8'], 'color-supported': True, 'compression-supported': [u'none', u'gzip'], 'copies-default': 1, 'copies-supported': (1, 9999), 'cups-version': u'1.7.2', 'device-uri': u'hp:/usb/HP_LaserJet_400_color_M451dn?serial=CNFF308670', 'document-format-default': u'application/octet-stream', 'document-format-supported': [u'application/octet-stream', u'application/pdf', u'application/postscript', u'application/vnd.adobe-reader-postscript', u'application/vnd.cups-command', u'application/vnd.cups-pdf', u'application/vnd.cups-pdf-banner', u'application/vnd.cups-postscript', u'application/vnd.cups-raw', u'application/vnd.samsung-ps', u'application/x-cshell', u'application/x-csource', u'application/x-perl', u'application/x-shell', u'image/gif', u'image/jpeg', u'image/png', u'image/tiff', u'image/urf', u'image/x-bitmap', u'image/x-photocd', u'image/x-portable-anymap', u'image/x-portable-bitmap', u'image/x-portable-graymap', u'image/x-portable-pixmap', u'image/x-sgi-rgb', u'image/x-sun-raster', u'image/x-xbitmap', u'image/x-xpixmap', u'image/x-xwindowdump', u'text/css', u'text/html', u'text/plain'], 'finishings-default': 3, 'finishings-supported': [3], 'generated-natural-language-supported': [u'en-us'], 'ipp-versions-supported': [u'1.0', u'1.1', u'2.0', u'2.1'], 'ippget-event-life': 15, 'job-creation-attributes-supported': [u'copies', u'finishings', u'ipp-attribute-fidelity', u'job-hold-until', u'job-name', u'job-priority', u'job-sheets', u'media', u'media-col', u'multiple-document-handling', u'number-up', u'output-bin', u'orientation-requested', u'page-ranges', u'print-color-mode', u'print-quality', u'printer-resolution', u'sides'], 'job-hold-until-default': u'no-hold', 'job-hold-until-supported': [u'no-hold', u'indefinite', u'day-time', u'evening', u'night', u'second-shift', u'third-shift', u'weekend'], 'job-ids-supported': True, 'job-k-limit': 0, 'job-k-octets-supported': (0, 470914416), 'job-page-limit': 0, 'job-priority-default': 50, 'job-priority-supported': [100], 'job-quota-period': 0, 'job-settable-attributes-supported': [u'copies', u'finishings', u'job-hold-until', u'job-name', u'job-priority', u'media', u'media-col', u'multiple-document-handling', u'number-up', u'output-bin', u'orientation-requested', u'page-ranges', u'print-color-mode', u'print-quality', u'printer-resolution', u'sides'], 'job-sheets-default': (u'none', u'none'), 'job-sheets-supported': [u'none', u'classified', u'confidential', u'form', u'secret', u'standard', u'topsecret', u'unclassified'], 'jpeg-k-octets-supported': (0, 470914416), 'jpeg-x-dimension-supported': (0, 65535), 'jpeg-y-dimension-supported': (1, 65535), 'marker-change-time': 0, 'media-bottom-margin-supported': [423], 'media-col-default': u'(unknown IPP value tag 0x34)', 'media-col-supported': [u'media-bottom-margin', u'media-left-margin', u'media-right-margin', u'media-size', u'media-source', u'media-top-margin', u'media-type'], 'media-default': u'iso_a4_210x297mm', 'media-left-margin-supported': [423], 'media-right-margin-supported': [423],

    Read the article

  • How to point GoDaddy to EntryDNS domain

    - by geminiCoder
    I have a server connected via dynamic IP. I have set up EntryDNS to manage the change of my IP. If I put in my EntryDNS URL it points me to my server's current IP. I purchased a domain from GoDaddy, but I have been unable to get it to point to my EntryDNS. What I want is to be able to ssh to my server, but ideally I'd like to do this by using my domain name. I must confess I'm a bit overwhelmed by the GoDaddy interface. So the bottom line is, how do I point my GoDaddy domain to my DNS domain so that when I look up the domain I get the current IP of the server?

    Read the article

  • Xcode Video From UITableView [migrated]

    - by Luis Felipe Beltran
    I have created different UITableViews. Each of these are dynamic tables that contain NSarrays of words. Right now When a cell is tabbed it takes the user to another View (simple view controller) that has a label and a UIImageview that displays a picture. My problem is that I also want to show video. Some of these words need to show pictures, and others need to show video. I have shown video before but I have done it using a button. I need help! I would appreciate if you guys could help here. Again, Im trying to show a video from a UITableView after the user tabs a cell. (I have many videos not just one, so dynamically would be better if possible)

    Read the article

  • Key ATG architecture principles

    - by Glen Borkowski
    Overview The purpose of this article is to describe some of the important foundational concepts of ATG.  This is not intended to cover all areas of the ATG platform, just the most important subset - the ones that allow ATG to be extremely flexible, configurable, high performance, etc.  For more information on these topics, please see the online product manuals. Modules The first concept is called the 'ATG Module'.  Simply put, you can think of modules as the building blocks for ATG applications.  The ATG development team builds the out of the box product using modules (these are the 'out of the box' modules).  Then, when a customer is implementing their site, they build their own modules that sit 'on top' of the out of the box ATG modules.  Modules can be very simple - containing minimal definition, and perhaps a small amount of configuration.  Alternatively, a module can be rather complex - containing custom logic, database schema definitions, configuration, one or more web applications, etc.  Modules generally will have dependencies on other modules (the modules beneath it).  For example, the Commerce Reference Store module (CRS) requires the DCS (out of the box commerce) module. Modules have a ton of value because they provide a way to decouple a customers implementation from the out of the box ATG modules.  This allows for a much easier job when it comes time to upgrade the ATG platform.  Modules are also a very useful way to group functionality into a single package which can be leveraged across multiple ATG applications. One very important thing to understand about modules, or more accurately, ATG as a whole, is that when you start ATG, you tell it what module(s) you want to start.  One of the first things ATG does is to look through all the modules you specified, and for each one, determine a list of modules that are also required to start (based on each modules dependencies).  Once this final, ordered list is determined, ATG continues to boot up.  One of the outputs from the ordered list of modules is that each module can contain it's own classes and configuration.  During boot, the ordered list of modules drives the unified classpath and configpath.  This is what determines which classes override others, and which configuration overrides other configuration.  Think of it as a layered approach. The structure of a module is well defined.  It simply looks like a folder in a filesystem that has certain other folders and files within it.  Here is a list of items that can appear in a module: MyModule: META-INF - this is required, along with a file called MANIFEST.MF which describes certain properties of the module.  One important property is what other modules this module depends on. config - this is typically present in most modules.  It defines a tree structure (folders containing properties files, XML, etc) that maps to ATG components (these are described below). lib - this contains the classes (typically in jarred format) for any code defined in this module j2ee - this is where any web-apps would be stored. src - in case you want to include the source code for this module, it's standard practice to put it here sql - if your module requires any additions to the database schema, you should place that schema here Here's a screenshots of a module: Modules can also contain sub-modules.  A dot-notation is used when referring to these sub-modules (i.e. MyModule.Versioned, where Versioned is a sub-module of MyModule). Finally, it is important to completely understand how modules work if you are going to be able to leverage them effectively.  There are many different ways to design modules you want to create, some approaches are better than others, especially if you plan to share functionality between multiple different ATG applications. Components A component in ATG can be thought of as a single item that performs a certain set of related tasks.  An example could be a ProductViews component - used to store information about what products the current customer has viewed.  Components have properties (also called attributes).  The ProductViews component could have properties like lastProductViewed (stores the ID of the last product viewed) or productViewList (stores the ID's of products viewed in order of their being viewed).  The previous examples of component properties would typically also offer get and set methods used to retrieve and store the property values.  Components typically will also offer other types of useful methods aside from get and set.  In the ProductViewed component, we might want to offer a hasViewed method which will tell you if the customer has viewed a certain product or not. Components are organized in a tree like hierarchy called 'nucleus'.  Nucleus is used to locate and instantiate ATG Components.  So, when you create a new ATG component, it will be able to be found 'within' nucleus.  Nucleus allows ATG components to reference one another - this is how components are strung together to perform meaningful work.  It's also a mechanism to prevent redundant configuration - define it once and refer to it from everywhere. Here is a screenshot of a component in nucleus:  Components can be extremely simple (i.e. a single property with a get method), or can be rather complex offering many properties and methods.  To be an ATG component, a few things are required: a class - you can reference an existing out of the box class or you could write your own a properties file - this is used to define your component the above items must be located 'within' nucleus by placing them in the correct spot in your module's config folder Within the properties file, you will need to point to the class you want to use: $class=com.mycompany.myclass You may also want to define the scope of the class (request, session, or global): $scope=session In summary, ATG Components live in nucleus, generally have links to other components, and provide some meaningful type of work.  You can configure components as well as extend their functionality by writing code. Repositories Repositories (a.k.a. Data Anywhere Architecture) is the mechanism that ATG uses to access data primarily stored in relational databases, but also LDAP or other backend systems.  ATG applications are required to be very high performance, and data access is critical in that if not handled properly, it could create a bottleneck.  ATG's repository functionality has been around for a long time - it's proven to be extremely scalable.  Developers new to ATG need to understand how repositories work as this is a critical aspect of the ATG architecture.   Repositories essentially map relational tables to objects in ATG, as well as handle caching.  ATG defines many repositories out of the box (i.e. user profile, catalog, orders, etc), and this is comprised of both the underlying database schema along with the associated repository definition files (XML).  It is fully expected that implementations will extend / change the out of the box repository definitions, so there is a prescribed approach to doing this.  The first thing to be sure of is to encapsulate your repository definition additions / changes within your own module (as described above).  The other important best practice is to never modify the out of the box schema - in other words, don't add columns to existing ATG tables, just create your own new tables.  These will help ensure you can easily upgrade your application at a later date. xml-combination As mentioned earlier, when you start ATG, the order of the modules will determine the final configpath.  Files within this configpath are 'layered' such that modules on top can override configuration of modules below it.  This is the same concept for repository definition files.  If you want to add a few properties to the out of the box user profile, you simply need to create an XML file containing only your additions, and place it in the correct location in your module.  At boot time, your definition will be combined (hence the term xml-combination) with the lower, out of the box modules, with the result being a user profile that contains everything (out of the box, plus your additions).  Aside from just adding properties, there are also ways to remove and change properties. types of properties Aside from the normal 'database backed' properties, there are a few other interesting types: transient properties - these are properties that are in memory, but not backed by any database column.  These are useful for temporary storage. java-backed properties - by nature, these are transient, but in addition, when you access this property (by called the get method) instead of looking up a piece of data, it performs some logic and returns the results.  'Age' is a good example - if you're storing a birth date on the profile, but your business rules are defined in terms of someones age, you could create a simple java-backed property to look at the birth date and compare it to the current date, and return the persons age. derived properties - this is what allows for inheritance within the repository structure.  You could define a property at the category level, and have the product inherit it's value as well as override it.  This is useful for setting defaults, with the ability to override. caching There are a number of different caching modes which are useful at different times depending on the nature of the data being cached.  For example, the simple cache mode is useful for things like user profiles.  This is because the user profile will typically only be used on a single instance of ATG at one time.  Simple cache mode is also useful for read-only types of data such as the product catalog.  Locked cache mode is useful when you need to ensure that only one ATG instance writes to a particular item at a time - an example would be a customers order.  There are many options in terms of configuring caching which are outside the scope of this article - please refer to the product manuals for more details. Other important concepts - out of scope for this article There are a whole host of concepts that are very important pieces to the ATG platform, but are out of scope for this article.  Here's a brief description of some of them: formhandlers - these are ATG components that handle form submissions by users. pipelines - these are configurable chains of logic that are used for things like handling a request (request pipeline) or checking out an order. special kinds of repositories (versioned, files, secure, ...) - there are a couple different types of repositories that are used in various situations.  See the manuals for more information. web development - JSP/ DSP tag library - ATG provides a traditional approach to developing web applications by providing a tag library called the DSP library.  This library is used throughout your JSP pages to interact with all the ATG components. messaging - a message sub-system used as another way for components to interact. personalization - ability for business users to define a personalized user experience for customers.  See the other blog posts related to personalization.

    Read the article

  • creating the nodes for path finding during run time - more like path making and more

    - by bigbadbabybear
    i'm making my 1st game. i'm using javascript as i currently want to learn to make games without needing to learn another language but this is more of a general game dev question its a 2d turn-based tile/grid game. you can check it here http://www.patinterotest.tk/ it creates a movable area when you hover a player and it implements the A* algo for moving the player. The Problem: i want to make the 'dynamic movable area creation' already implement a limited number of steps for a player. The Questions: what is a good way to do this? is there another algorithm to use for this? the A* algorithm needs a start and destination, with what i want to do i don't have a destination or should i just limit the iteration of the A* algo to the steps variable? hopefully you understand the problem & questions easily

    Read the article

  • Installing old Loki games on 12.04 64-bit results in no audio

    - by FlabbergastedPickle
    All, Here's an interesting problem. I followed instructions provided online for installing Loki Games' Heroes of Might and Magic 3 (see http://www.swanson.ukfsn.org/loki/ and http://wtanaka.com/node/7641) and got it installed and patched to the latest version. However, every time I start it regardless whether the pulseaudio is running, I get the following error: LD_LIBRARY_PATH=/usr/local/lib/Loki_Compat/ /usr/local/lib/Loki_Compat/ld-linux.so.2 /usr/local/games/Heroes3/heroes3.dynamic ALSA lib conf.c:3314:(snd_config_hooks_call) Cannot open shared library libasound_module_conf_pulse.so ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM default Couldn't open audio: My first soundcard is HDMI output and my second one is the actual soundcard (HP DM1 running 12.04 64-bit with latest updates). I did set up /etc/asound.conf as follows: asound.conf pcm.!default { type hw card 1 } ctl.!default { type hw card 1 } So, the default soundcard should work ok. Between Shadowgrounds that also stopped working and this it appears a there may be some unfinished business/regressions in 32-bit support on 64-bit systems in 12.04. Any thoughts?

    Read the article

  • Avoid GPL violation by moving library out of process

    - by Andrey
    Assume there is a library that is licensed under GPL. I want to use it is closed source project. I do following: Create small wrapper application around that GPL library that listens to socket, parse messages and call GPL library. Then returns results back. Release it's sources (to comply with GPL) Create client for this wrapper in my main application and don't release sources. I know that this adds huge overhead compared to static/dynamic linking, but I am interested in theoretical way.

    Read the article

  • What are some client-side sitemap generators?

    - by BHare
    Most of the sitemap generators I've found all scan my internal files and base it on that. However using apache and htaccess I have many aliases for things for example: /brand/model/photos/ is empty directory wise, but on the web it relocates it to a zenphoto gallery using htaccess. http://www.xml-sitemaps.com/ does What I need, but I'd like to have more control over it and I need it to be dynamic and run weekly or daily. Allow for specific change frequencies based on the file/directory. I also want to be able to make a "pretty" sitemap html file. Counting the photo gallery I have around 300 links, without the photo gallery more like 100. I have MySQL, PHP 5.3 installed.

    Read the article

  • Can SpriteBatch be used to fill a polygon with a texture?

    - by can poyrazoglu
    I basically need to fill a texture into a polygon using the SpriteBatch. I've done some research but couldn't find anything useful except polygon triangulation method, which works well only with convex polygons (without diving into super math which is definitely not something I'm pretty good at). Are there any solutions for filling in a polygon in a basic way? I of course need something dynamic (I'll have a map editor that you can define polygons, and the game will render them (and collision detection will also use them but that's off topic), basically I can't accept solutions like "pre-calculated" bitmaps or anything like that. I need to draw a polygon with the segments provided, to the screen, using the SpriteBatch.

    Read the article

  • Why unhandled exceptions are useful

    - by Simon Cooper
    It’s the bane of most programmers’ lives – an unhandled exception causes your application or webapp to crash, an ugly dialog gets displayed to the user, and they come complaining to you. Then, somehow, you need to figure out what went wrong. Hopefully, you’ve got a log file, or some other way of reporting unhandled exceptions (obligatory employer plug: SmartAssembly reports an application’s unhandled exceptions straight to you, along with the entire state of the stack and variables at that point). If not, you have to try and replicate it yourself, or do some psychic debugging to try and figure out what’s wrong. However, it’s good that the program crashed. Or, more precisely, it is correct behaviour. An unhandled exception in your application means that, somewhere in your code, there is an assumption that you made that is actually invalid. Coding assumptions Let me explain a bit more. Every method, every line of code you write, depends on implicit assumptions that you have made. Take this following simple method, that copies a collection to an array and includes an item if it isn’t in the collection already, using a supplied IEqualityComparer: public static T[] ToArrayWithItem( ICollection<T> coll, T obj, IEqualityComparer<T> comparer) { // check if the object is in collection already // using the supplied comparer foreach (var item in coll) { if (comparer.Equals(item, obj)) { // it's in the collection already // simply copy the collection to an array // and return it T[] array = new T[coll.Count]; coll.CopyTo(array, 0); return array; } } // not in the collection // copy coll to an array, and add obj to it // then return it T[] array = new T[coll.Count+1]; coll.CopyTo(array, 0); array[array.Length-1] = obj; return array; } What’s all the assumptions made by this fairly simple bit of code? coll is never null comparer is never null coll.CopyTo(array, 0) will copy all the items in the collection into the array, in the order defined for the collection, starting at the first item in the array. The enumerator for coll returns all the items in the collection, in the order defined for the collection comparer.Equals returns true if the items are equal (for whatever definition of ‘equal’ the comparer uses), false otherwise comparer.Equals, coll.CopyTo, and the coll enumerator will never throw an exception or hang for any possible input and any possible values of T coll will have less than 4 billion items in it (this is a built-in limit of the CLR) array won’t be more than 2GB, both on 32 and 64-bit systems, for any possible values of T (again, a limit of the CLR) There are no threads that will modify coll while this method is running and, more esoterically: The C# compiler will compile this code to IL according to the C# specification The CLR and JIT compiler will produce machine code to execute the IL on the user’s computer The computer will execute the machine code correctly That’s a lot of assumptions. Now, it could be that all these assumptions are valid for the situations this method is called. But if this does crash out with an exception, or crash later on, then that shows one of the assumptions has been invalidated somehow. An unhandled exception shows that your code is running in a situation which you did not anticipate, and there is something about how your code runs that you do not understand. Debugging the problem is the process of learning more about the new situation and how your code interacts with it. When you understand the problem, the solution is (usually) obvious. The solution may be a one-line fix, the rewrite of a method or class, or a large-scale refactoring of the codebase, but whatever it is, the fix for the crash will incorporate the new information you’ve gained about your own code, along with the modified assumptions. When code is running with an assumption or invariant it depended on broken, then the result is ‘undefined behaviour’. Anything can happen, up to and including formatting the entire disk or making the user’s computer sentient and start doing a good impression of Skynet. You might think that those can’t happen, but at Halting problem levels of generality, as soon as an assumption the code depended on is broken, the program can do anything. That is why it’s important to fail-fast and stop the program as soon as an invariant is broken, to minimise the damage that is done. What does this mean in practice? To start with, document and check your assumptions. As with most things, there is a level of judgement required. How you check and document your assumptions depends on how the code is used (that’s some more assumptions you’ve made), how likely it is a method will be passed invalid arguments or called in an invalid state, how likely it is the assumptions will be broken, how expensive it is to check the assumptions, and how bad things are likely to get if the assumptions are broken. Now, some assumptions you can assume unless proven otherwise. You can safely assume the C# compiler, CLR, and computer all run the method correctly, unless you have evidence of a compiler, CLR or processor bug. You can also assume that interface implementations work the way you expect them to; implementing an interface is more than simply declaring methods with certain signatures in your type. The behaviour of those methods, and how they work, is part of the interface contract as well. For example, for members of a public API, it is very important to document your assumptions and check your state before running the bulk of the method, throwing ArgumentException, ArgumentNullException, InvalidOperationException, or another exception type as appropriate if the input or state is wrong. For internal and private methods, it is less important. If a private method expects collection items in a certain order, then you don’t necessarily need to explicitly check it in code, but you can add comments or documentation specifying what state you expect the collection to be in at a certain point. That way, anyone debugging your code can immediately see what’s wrong if this does ever become an issue. You can also use DEBUG preprocessor blocks and Debug.Assert to document and check your assumptions without incurring a performance hit in release builds. On my coding soapbox… A few pet peeves of mine around assumptions. Firstly, catch-all try blocks: try { ... } catch { } A catch-all hides exceptions generated by broken assumptions, and lets the program carry on in an unknown state. Later, an exception is likely to be generated due to further broken assumptions due to the unknown state, causing difficulties when debugging as the catch-all has hidden the original problem. It’s much better to let the program crash straight away, so you know where the problem is. You should only use a catch-all if you are sure that any exception generated in the try block is safe to ignore. That’s a pretty big ask! Secondly, using as when you should be casting. Doing this: (obj as IFoo).Method(); or this: IFoo foo = obj as IFoo; ... foo.Method(); when you should be doing this: ((IFoo)obj).Method(); or this: IFoo foo = (IFoo)obj; ... foo.Method(); There’s an assumption here that obj will always implement IFoo. If it doesn’t, then by using as instead of a cast you’ve turned an obvious InvalidCastException at the point of the cast that will probably tell you what type obj actually is, into a non-obvious NullReferenceException at some later point that gives you no information at all. If you believe obj is always an IFoo, then say so in code! Let it fail-fast if not, then it’s far easier to figure out what’s wrong. Thirdly, document your assumptions. If an algorithm depends on a non-trivial relationship between several objects or variables, then say so. A single-line comment will do. Don’t leave it up to whoever’s debugging your code after you to figure it out. Conclusion It’s better to crash out and fail-fast when an assumption is broken. If it doesn’t, then there’s likely to be further crashes along the way that hide the original problem. Or, even worse, your program will be running in an undefined state, where anything can happen. Unhandled exceptions aren’t good per-se, but they give you some very useful information about your code that you didn’t know before. And that can only be a good thing.

    Read the article

< Previous Page | 263 264 265 266 267 268 269 270 271 272 273 274  | Next Page >