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BRE (Business Rules Engine) Data Services is out...!!!

- by Vishal

A few months ago we at Tellago had open sourced the BizTalk Data Services. We were meanwhile working on other artifacts which comes along with BizTalk Server like the “Business Rules Engine”. We are happy to announce the first version of BRE Data Services. BRE Data Services is a same concept which we covered through BTS Data Services, providing a RESTFul OData – based API to interact with the Business Rules Engine via HTTP using ATOM Publishing Protocol or JSON as the encoding mechanism. In the first version release, we mainly focused on the browsing, querying and searching BRE artifacts via a RESTFul interface. Also along with that we provide the functionality to execute Business Rules by inserting the Facts for policies via the IUpdatable implementation of WCF Data Services. The BRE Data Services API provides a lightweight interface for managing Business Rules Engine artifacts such as Policies, Rules, Vocabularies, Conditions, Actions, Facts etc. The following are some examples which details some of the available features in the current version of the API. Basic Querying: Querying BRE Policies http://localhost/BREDataServices/BREMananagementService.svc/Policies Querying BRE Rules http://localhost/BREDataServices/BREMananagementService.svc/Rules Querying BRE Vocabularies http://localhost/BREDataServices/BREMananagementService.svc/Vocabularies Navigation: The BRE Data Services API also leverages WCF Data Services to enable navigation across related different BRE objects. Querying a specific Policy http://localhost/BREDataServices/BREMananagementService.svc/Policies(‘PolicyName’) Querying a specific Rule http://localhost/BREDataServices/BREMananagementService.svc/Rules(‘RuleName’) Querying all Rules under a Policy http://localhost/BREDataServices/BREMananagementService.svc/Policies('PolicyName')/Rules Querying all Facts under a Policy http://localhost/BREDataServices/BREMananagementService.svc/Policies('PolicyName')/Facts Querying all Actions for a specific Rule http://localhost/BREDataServices/BREMananagementService.svc/Rules('RuleName')/Actions Querying all Conditions for a specific Rule http://localhost/BREDataServices/BREMananagementService.svc/Rules('RuleName')/Actions Querying a specific Vocabulary: http://localhost/BREDataServices/BREMananagementService.svc/Vocabularies('VocabName') Implementation: With the BRE Data Services, we also provide the functionality of executing a particular policy via HTTP. There are couple of ways you can do that though the API. Ø First is though Service Operations feature of WCF Data Services in which you can execute the Facts by passing them in the URL itself. This is a very simple implementations of the executing the policies due to the limitations & restrictions (only primitive types of input parameters which can be passed) currently of the Service Operations of the WCF Data Services. Below is a code sample. Below is a traced Request/Response message. Ø Second is through the IUpdatable Interface of WCF Data Services. In this method, you can first query the rule which you want to execute and then inserts Facts for that particular Rules and finally when you perform the SaveChanges() call for the IUpdatable Interface API, it executes the policy with the facts which you inserted at runtime. Below is a sample of client side code. Due to the limitations of current version of WCF Data Services where there is no way you can return back the updates happening on the service side back to the client via the SaveChanges() method. Here we are executing the rule passing a serialized XML as Facts and there is no changes made to any data where we can query back to fetch the changes. This is overcome though the first way to executing the policies which is by executing it as a Service Operation call. This actually generates a AtomPub message shown as below: POST /Tellago.BRE.REST.ServiceHost/BREMananagementService.svc/$batch HTTP/1.1 User-Agent: Microsoft ADO.NET Data Services DataServiceVersion: 1.0;NetFx MaxDataServiceVersion: 2.0;NetFx Accept: application/atom+xml,application/xml Accept-Charset: UTF-8 Content-Type: multipart/mixed; boundary=batch_6b9a5ced-5ecb-4585-940a-9d5e704c28c7 Host: localhost:8080 Content-Length: 1481 Expect: 100-continue --batch_6b9a5ced-5ecb-4585-940a-9d5e704c28c7 Content-Type: multipart/mixed; boundary=changeset_184a8c59-a714-4ba9-bb3d-889a88fe24bf --changeset_184a8c59-a714-4ba9-bb3d-889a88fe24bf Content-Type: application/http Content-Transfer-Encoding: binary MERGE http://localhost:8080/Tellago.BRE.REST.ServiceHost/BREMananagementService.svc/Facts('TestPolicy') HTTP/1.1 Content-ID: 4 Content-Type: application/atom+xml;type=entry Content-Length: 927 <?xml version="1.0" encoding="utf-8" standalone="yes"?> <entry xmlns:d="http://schemas.microsoft.com/ado/2007/08/dataservices" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata" font-size: x-small"http://www.w3.org/2005/Atom"> <category scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme" term="Tellago.BRE.REST.Resources.Fact" /> <title /> <author> <name /> </author> <updated>2011-01-31T20:09:15.0023982Z</updated> <id>http://localhost:8080/Tellago.BRE.REST.ServiceHost/BREMananagementService.svc/Facts('TestPolicy')</id> <content type="application/xml"> <m:properties> <d:FactInstance><ns0:LoanStatus xmlns:ns0="http://tellago.com"><Age>10</Age><Status>true</Status></ns0:LoanStatus></d:FactInstance> <d:FactType>TestSchema</d:FactType> <d:ID>TestPolicy</d:ID> </m:properties> </content> </entry> --changeset_184a8c59-a714-4ba9-bb3d-889a88fe24bf-- --batch_6b9a5ced-5ecb-4585-940a-9d5e704c28c7— Installation: The installation of the BRE Data Services is pretty straight forward. · Create a new IIS website say BREDataServices. · Download the SourceCode from TellagoCodeplex and copy the content from Tellago.BRE.REST.ServiceHost to the physical location of the above created website. · The appPool account running the website should have admin access to the BizTalkRuleEngineDb database. · TheRight click the BREManagementService.svc in the IIS ContentView for the website and wala.. Conclusion: The BRE Data Services API is an experiment intended to bring the capabilities of RESTful/OData based services to the Traditional BTS/BRE Solutions. The future releases will target on technologies like BAM, ESB Toolkit. This version has been tested with various version of BizTalk Server and we have uploaded the source code to our Tellago's DevLabs workspace at Codeplex. I hope you guys enjoy this release. Keep an eye on our new releases @ Tellago Codeplex. We are working on various other Biztalk Artifacts like BAM, ESB Toolkit. Till than happy BizzRuling…!!! Thanks, Vishal Mody

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How to create a virtual network with Azure Connect

- by Herve Roggero

If you are trying to establish a virtual network between machines located in disparate networks, you can either use VPN, Virtual Network or Azure Connect. If you want to establish a connection between machines located in Windows Azure, you should consider using the Virtual Network service. If you want to establish a connection between local machines and Virtual Machines in Windows Azure, you may be able to use your existing VPN device (assuming you have one), as long as the device is supported by Microsoft. If the VPN device you are using isn’t supported, or if you are trying to create a virtual network between machines from disparate networks (such as machines located in another cloud provider), you can use Azure Connect. This blog post explains how Azure Connect can help you create virtual networks between multiple servers in the cloud, various servers in different cloud environments, and on-premise. Note: Azure Connect is currently in Technical Preview. About Azure Connect Let’s do a quick review of Azure Connect. This technology implements an IPSec tunnel from machines to to a relay service located in the Microsoft cloud (Azure). So in essence, Azure Connect doesn’t provide a point-to-point connection between machines; the network communication is tunneled through the relay service. The relay service in turn offers a mechanism to enforce basic communication rules that you define through Groups. We will review this later. You could network two or more VMs in the Azure cloud (although you should consider using a Virtual Network if you go this route), or servers in the Azure cloud and other machines in the Amazon cloud for example, or even two or more on-premise servers located in different locations for which a direct network connection is not an option. You can place any number of machines in your topology. Azure Connect gives you great flexibility on how you want to build your virtual network across various environments. So Azure Connect makes sense when you want to: Connect machines located in different cloud providers Connect on-premise machines running in different locations Connect Azure VMs with on-premise (if you do not have a VPN device, or if your device is not supported) Connect Azure Roles (Worker Roles, Web Roles) with on-premise servers or in other cloud providers The diagram below shows you a high level network topology that involves machines in the Windows Azure cloud, other cloud providers and on-premise. You should note that the only required component in this diagram is the Relay itself. The other machines are optional (although your network is useful only if you have two or more machines involved). Relay agents are currently available in three geographic areas: US, Europe and Asia. You can change which region you want to use in the Windows Azure management portal. High Level Network Topology With Azure Connect Azure Connect Agent Azure Connect establishes a virtual network and creates virtual adapters on your machines; these virtual adapters communicate through the Relay using IPSec. This is achieved by installing an agent (the Azure Connect Agent) on all the machines you want in your network topology. However, you do not need to install the agent on Worker Roles and Web Roles; that’s because the agent is already installed for you. Any other machine, including Virtual Machines in Windows Azure, needs the agent installed. To install the agent, simply go to your Windows Azure portal (http://windows.azure.com) and click on Networks on the bottom left panel. You will see a list of subscriptions under Connect. If you select a subscription, you will be able to click on the Install Local Endpoint icon on top. Clicking on this icon will begin the download and installation process for the agent. Activating Roles for Azure Connect As previously mentioned, you do not need to install the Azure Connect Agent on Worker Roles and Web Roles because it is already loaded. However, you do need to activate them if you want the roles to participate in your network topology. To do this, you will need to click on the Get Activation Token icon. The activation token must then be copied and placed in the configuration file of your roles. For more information on how to perform this step, visit MSDN at http://msdn.microsoft.com/en-us/library/windowsazure/gg432964.aspx. Firewall Rules Note that specific firewall rules must exist to allow the agent to communicate through the Relay. You will need to allow TCP 443 and ICMPv6. For additional information, please visit MSDN at http://msdn.microsoft.com/en-us/library/windowsazure/gg433061.aspx. CA Certificates You can optionally require agents to sign their activation request with the Relay using a trusted certificate issued by a Certificate Authority (CA). Click on Activation Options to learn more. Groups To create your network topology you must first create a group. A group represents a logical container of endpoints (or machines) that can communicate through the Relay. You can create multiple groups allowing you to manage network communication differently. For example you could create a DEVELOPMENT group and a PRODUCTION group. To add an endpoint you must first install an agent that will create a virtual adapter on the machine on which it is installed (as discussed in the previous section). Once you have created a group and installed the agents, the machines will appear in the Windows Azure management portal and you can start assigning machines to groups. The next figure shows you that I created a group called LocalGroup and assigned two machines (both on-premise) to that group. Groups and Computers in Azure Connect As I mentioned previously you can allow these machines to establish a network connection. To do this, you must enable the Interconnected option in the group. The following diagram shows you the definition of the group. In this topology I chose to include local machines only, but I could also add worker roles and web roles in the Azure Roles section (you must first activate your roles, as discussed previously). You could also add other Groups, allowing you to manage inter-group communication. Defining a Group in Azure Connect Testing the Connection Now that my agents have been installed on my two machines, the group defined and the Interconnected option checked, I can test the connection between my machines. The next screenshot shows you that I sent a PING request to DEVLAP02 from DEVDSK02. The PING request was successful. Note however that the time is in the hundreds of milliseconds on average. That is to be expected because the machines are connecting through the Relay located in the cloud. Going through the Relay introduces an extra hop in the communication chain, so if your systems rely on high performance, you may want to conduct some basic performance tests. Sending a PING Request Through The Relay Conclusion As you can see, creating a network topology between machines using the Azure Connect service is simple. It took me less than five minutes to create the above configuration, including the time it took to install the Azure Connect agents on the two machines. The flexibility of Azure Connect allows you to create a virtual network between disparate environments, as long as your operating systems are supported by the agent. For more information on Azure Connect, visit the MSDN website at http://msdn.microsoft.com/en-us/library/windowsazure/gg432997.aspx. About Herve Roggero Herve Roggero, Windows Azure MVP, is the founder of Blue Syntax Consulting, a company specialized in cloud computing products and services. Herve's experience includes software development, architecture, database administration and senior management with both global corporations and startup companies. Herve holds multiple certifications, including an MCDBA, MCSE, MCSD. He also holds a Master's degree in Business Administration from Indiana University. Herve is the co-author of "PRO SQL Azure" from Apress and runs the Azure Florida Association (on LinkedIn: http://www.linkedin.com/groups?gid=4177626). For more information on Blue Syntax Consulting, visit www.bluesyntax.net. Special Thanks I would like thank those that helped me figure out how Azure Connect works: Marcel Meijer - http://blogs.msmvps.com/marcelmeijer/ Michael Wood - Http://www.mvwood.com Glenn Block - http://www.codebetter.com/glennblock Yves Goeleven - http://cloudshaper.wordpress.com/ Sandrino Di Mattia - http://fabriccontroller.net/ Mike Martin - http://techmike2kx.wordpress.com

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Spacewalk 2.0 provided to manage Oracle Linux systems

- by wcoekaer

Oracle Linux customers have a few options to manage and provision their servers. We provide a license to use Oracle Enterprise Manager's Linux OS management, monitoring and provisioning features without additional cost for every server that has an Oracle Linux support subscription. So there is no additional pack to license and no additional per server cost, it's all included in our Basic, Premier and Systems support subscriptions. The nice thing with Oracle Enterprise Manager is that you end up with a single management product that can manage all aspects of your software stack. You have complete insight into the applications running, you have roles and responsibilities, you have third party connectors for storage or other products and it makes it very easy and convenient to correlate data and events when something happens. If you use Oracle VM as well, you end up with a complete cloud portal with selfservice, chargeback, etc... Another, much simpler option, is just using yum. It is very easy to take a server and create directories and expose these through apache as repositories. You can have a simple yum config on each server pointing to a few specific repositories. It requires some manual effort in terms of creating directories, downloading packages and creating local repo files but it's easy to do and for many people a preferred solution. There are also a good number of customers that just connect their servers directly to ULN or to our free update server public-yum. Just to re-iterate, our public-yum servers have all the errata and updates available for free. Now we added another option. Many of our customers have switched from a competing Linux vendor and they had familiarity with their management tools. Switching to Oracle for support is very easy since we don't require changes to the installed servers but we also want to make sure there is a very easy and almost transparent switch for the management tools as well. While Oracle Enterprise Manager is our preferred way of managing systems, we now are offering Spacewalk 2.0 to our customers. The community project can be found here. We have made a few changes to ensure easy and complete support for Oracle Linux, tested it with public-yum, etc.. You can find the rpms in our public-yum repos at http://public-yum.oracle.com/repo/OracleLinux/OL6/. There are repositories for spacewalk server and then for each version (OL5,OL6) and architecture (x86 and x86-64) we have the client repositories as well. Spacewalk itself is only made available for OL6 x86-64. Documentation can be found here. I set it up myself and here are some quick steps on how you can get going in just a matter of minutes: Spacewalk Server Installation : 1) Installing an Oracle Database Use an existing Oracle Database or install a new Oracle Database (Standard or Enterprise Edition) [at this time use 11g, we will add support for 12c in the near future]. This database can be installed on the spacewalk server or on a separate remote server. While Oracle XE might work to create a small sample POC, we do not support the use of Oracle XE, spacewalk repositories can become large and create a significant database workload. Customers can use their existing database licenses, they can download the database with a trial licence from http://edelivery.oracle.com or Oracle Linux subscribers (customers) will be allowed to use the Oracle Database as a spacewalk repository as part of their Oracle Linux subscription at no additional cost. |NOTE : spacewalk requires the database to be configured with the UTF8 characterset. |Installation will fail if your database does not use UTF8. |To verify if your database is configured correctly, run the following command in sqlplus: | |select value from nls_database_parameters where parameter='NLS_CHARACTERSET'; |This should return 'AL32UTF8' 2) Configure the database schema for spacewalk Ideally, create a tablespace in the database to hold the spacewalk schema tables/data; create tablespace spacewalk datafile '/u01/app/oracle/oradata/orcl/spacewalk.dbf' size 10G autoextend on; Create the database user spacewalk (or use some other schema name) in sqlplus. example : create user spacewalk identified by spacewalk; grant connect, resource to spacewalk; grant create table, create trigger, create synonym, create view, alter session to spacewalk; grant unlimited tablespace to spacewalk; alter user spacewalk default tablespace spacewalk; 4) Spacewalk installation and configuration Spacewalk server requires an Oracle Linux 6 x86-64 system. Clients can be Oracle Linux 5 or 6, both 32- and 64bit. The server is only supported on OL6/64bit. The easiest way to get started is to do a 'Minimal' install of Oracle Linux on a server and configure the yum repository to include the spacewalk repo from public-yum. Once you have a system with a minimal install, modify your yum repo to include the spacewalk repo. Example : edit /etc/yum.repos.d/public-yum-ol.repo and add the following lines at the end of the file : [spacewalk] name=spacewalk baseurl=http://public-yum.oracle.com/repo/OracleLinux/OL6/spacewalk20/server/$basearch/ gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-ol6 gpgcheck=1 enabled=1 Install the following pre-requisite packages on your spacewalk server : oracle-instantclient11.2-basic-11.2.0.3.0-1.x86_64 oracle-instantclient11.2-sqlplus-11.2.0.3.0-1.x86_64 rpm -ivh oracle-instantclient11.2-basic-11.2.0.3.0-1.x86_64 rpm -ivh oracle-instantclient11.2-sqlplus-11.2.0.3.0-1.x86_64 The above RPMs can be found on the Oracle Technology Network website : http://www.oracle.com/technetwork/topics/linuxx86-64soft-092277.html As the root user, configure the library path to include the Oracle Instant Client libraries : cd /etc/ld.so.conf.d echo /usr/lib/oracle/11.2/client64/lib oracle-instantclient11.2.conf ldconfig Install spacewalk : # yum install spacewalk-oracle The above yum command should download and install all required packages to run spacewalk on your local server. | NOTE : if you did a full, desktop or workstation installation, | you have to remove the JTA package | BEFORE installing spacewalk-oracle (rpm -e --nodeps jta) Once the installation completes, simply run the spacewalk configuration tool and you are all set. (make sure to run the command with the 2 arguments) spacewalk-setup --disconnected --external-db Answer the questions during the setup, ensure you provide the current database user (example : spacewalk) and password (example : spacewalk) and database server hostname (the standard hostname of the server on which you have deployed the Oracle database) At the end of the setup script, your spacewalk server should be fully configured and you can log into the web portal. Use your favorite browser to connect to the website : http://[spacewalkserverhostname] The very first action will be to create the main admin account.

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How to Identify Which Hardware Component is Failing in Your Computer

- by Chris Hoffman

Concluding that your computer has a hardware problem is just the first step. If you’re dealing with a hardware issue and not a software issue, the next step is determining what hardware problem you’re actually dealing with. If you purchased a laptop or pre-built desktop PC and it’s still under warranty, you don’t need to care about this. Have the manufacturer fix the PC for you — figuring it out is their problem. If you’ve built your own PC or you want to fix a computer that’s out of warranty, this is something you’ll need to do on your own. Blue Screen 101: Search for the Error Message This may seem like obvious advice, but searching for information about a blue screen’s error message can help immensely. Most blue screens of death you’ll encounter on modern versions of Windows will likely be caused by hardware failures. The blue screen of death often displays information about the driver that crashed or the type of error it encountered. For example, let’s say you encounter a blue screen that identified “NV4_disp.dll” as the driver that caused the blue screen. A quick Google search will reveal that this is the driver for NVIDIA graphics cards, so you now have somewhere to start. It’s possible that your graphics card is failing if you encounter such an error message. Check Hard Drive SMART Status Hard drives have a built in S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) feature. The idea is that the hard drive monitors itself and will notice if it starts to fail, providing you with some advance notice before the drive fails completely. This isn’t perfect, so your hard drive may fail even if SMART says everything is okay. If you see any sort of “SMART error” message, your hard drive is failing. You can use SMART analysis tools to view the SMART health status information your hard drives are reporting. Test Your RAM RAM failure can result in a variety of problems. If the computer writes data to RAM and the RAM returns different data because it’s malfunctioning, you may see application crashes, blue screens, and file system corruption. To test your memory and see if it’s working properly, use Windows’ built-in Memory Diagnostic tool. The Memory Diagnostic tool will write data to every sector of your RAM and read it back afterwards, ensuring that all your RAM is working properly. Check Heat Levels How hot is is inside your computer? Overheating can rsult in blue screens, crashes, and abrupt shut downs. Your computer may be overheating because you’re in a very hot location, it’s ventilated poorly, a fan has stopped inside your computer, or it’s full of dust. Your computer monitors its own internal temperatures and you can access this information. It’s generally available in your computer’s BIOS, but you can also view it with system information utilities such as SpeedFan or Speccy. Check your computer’s recommended temperature level and ensure it’s within the appropriate range. If your computer is overheating, you may see problems only when you’re doing something demanding, such as playing a game that stresses your CPU and graphics card. Be sure to keep an eye on how hot your computer gets when it performs these demanding tasks, not only when it’s idle. Stress Test Your CPU You can use a utility like Prime95 to stress test your CPU. Such a utility will fore your computer’s CPU to perform calculations without allowing it to rest, working it hard and generating heat. If your CPU is becoming too hot, you’ll start to see errors or system crashes. Overclockers use Prime95 to stress test their overclock settings — if Prime95 experiences errors, they throttle back on their overclocks to ensure the CPU runs cooler and more stable. It’s a good way to check if your CPU is stable under load. Stress Test Your Graphics Card Your graphics card can also be stress tested. For example, if your graphics driver crashes while playing games, the games themselves crash, or you see odd graphical corruption, you can run a graphics benchmark utility like 3DMark. The benchmark will stress your graphics card and, if it’s overheating or failing under load, you’ll see graphical problems, crashes, or blue screens while running the benchmark. If the benchmark seems to work fine but you have issues playing a certain game, it may just be a problem with that game. Swap it Out Not every hardware problem is easy to diagnose. If you have a bad motherboard or power supply, their problems may only manifest through occasional odd issues with other components. It’s hard to tell if these components are causing problems unless you replace them completely. Ultimately, the best way to determine whether a component is faulty is to swap it out. For example, if you think your graphics card may be causing your computer to blue screen, pull the graphics card out of your computer and swap in a new graphics card. If everything is working well, it’s likely that your previous graphics card was bad. This isn’t easy for people who don’t have boxes of components sitting around, but it’s the ideal way to troubleshoot. Troubleshooting is all about trial and error, and swapping components out allows you to pin down which component is actually causing the problem through a process of elimination. This isn’t a complete guide to everything that could likely go wrong and how to identify it — someone could write a full textbook on identifying failing components and still not cover everything. But the tips above should give you some places to start dealing with the more common problems. Image Credit: Justin Marty on Flickr

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RIF PRD: Presentation syntax issues

- by Charles Young

Over Christmas I got to play a bit with the W3C RIF PRD and came across a few issues which I thought I would record for posterity. Specifically, I was working on a grammar for the presentation syntax using a GLR grammar parser tool (I was using the current CTP of ‘M’ (MGrammer) and Intellipad – I do so hope the MS guys don’t kill off M and Intellipad now they have dropped the other parts of SQL Server Modelling). I realise that the presentation syntax is non-normative and that any issues with it do not therefore compromise the standard. However, presentation syntax is useful in its own right, and it would be great to iron out any issues in a future revision of the standard. The main issues are actually not to do with the grammar at all, but rather with the ‘running example’ in the RIF PRD recommendation. I started with the code provided in Example 9.1. There are several discrepancies when compared with the EBNF rules documented in the standard. Broadly the problems can be categorised as follows: · Parenthesis mismatch – the wrong number of parentheses are used in various places. For example, in GoldRule, the RHS of the rule (the ‘Then’) is nested in the LHS (‘the If’). In NewCustomerAndWidgetRule, the RHS is orphaned from the LHS. Together with additional incorrect parenthesis, this leads to orphanage of UnknownStatusRule from the entire Document. · Invalid use of parenthesis in ‘Forall’ constructs. Parenthesis should not be used to enclose formulae. Removal of the invalid parenthesis gave me a feeling of inconsistency when comparing formulae in Forall to formulae in If. The use of parenthesis is not actually inconsistent in these two context, but in an If construct it ‘feels’ as if you are enclosing formulae in parenthesis in a LISP-like fashion. In reality, the parenthesis is simply being used to group subordinate syntax elements. The fact that an If construct can contain only a single formula as an immediate child adds to this feeling of inconsistency. · Invalid representation of compact URIs (CURIEs) in the context of Frame productions. In several places the URIs are not qualified with a namespace prefix (‘ex1:’). This conflicts with the definition of CURIEs in the RIF Datatypes and Built-Ins 1.0 document. Here are the productions: CURIE ::= PNAME_LN | PNAME_NS PNAME_LN ::= PNAME_NS PN_LOCAL PNAME_NS ::= PN_PREFIX? ':' PN_LOCAL ::= ( PN_CHARS_U | [0-9] ) ((PN_CHARS|'.')* PN_CHARS)? PN_CHARS ::= PN_CHARS_U | '-' | [0-9] | #x00B7 | [#x0300-#x036F] | [#x203F-#x2040] PN_CHARS_U ::= PN_CHARS_BASE | '_' PN_CHARS_BASE ::= [A-Z] | [a-z] | [#x00C0-#x00D6] | [#x00D8-#x00F6] | [#x00F8-#x02FF] | [#x0370-#x037D] | [#x037F-#x1FFF] | [#x200C-#x200D] | [#x2070-#x218F] | [#x2C00-#x2FEF] | [#x3001-#xD7FF] | [#xF900-#xFDCF] | [#xFDF0-#xFFFD] | [#x10000-#xEFFFF] PN_PREFIX ::= PN_CHARS_BASE ((PN_CHARS|'.')* PN_CHARS)? The more I look at CURIEs, the more my head hurts! The RIF specification allows prefixes and colons without local names, which surprised me. However, the CURIE Syntax 1.0 working group note specifically states that this form is supported…and then promptly provides a syntactic definition that seems to preclude it! However, on (much) deeper inspection, it appears that ‘ex1:’ (for example) is allowed, but would really represent a ‘fragment’ of the ‘reference’, rather than a prefix! Ouch! This is so completely ambiguous that it surely calls into question the whole CURIE specification. In any case, RIF does not allow local names without a prefix. · Missing ‘External’ specifiers for built-in functions and predicates. The EBNF specification enforces this for terms within frames, but does not appear to enforce (what I believe is) the correct use of External on built-in predicates. In any case, the running example only specifies ‘External’ once on the predicate in UnknownStatusRule. External() is required in several other places. · The List used on the LHS of UnknownStatusRule is comma-delimited. This is not supported by the EBNF definition. Similarly, the argument list of pred:list-contains is illegally comma-delimited. · Unnecessary use of conjunction around a single formula in DiscountRule. This is strictly legal in the EBNF, but redundant. All the above issues concern the presentation syntax used in the running example. There are a few minor issues with the grammar itself. Note that Michael Kiefer stated in his paper “Rule Interchange Format: The Framework” that: “The presentation syntax of RIF … is an abstract syntax and, as such, it omits certain details that might be important for unambiguous parsing.” · The grammar cannot differentiate unambiguously between strategies and priorities on groups. A processor is forced to resolve this by detecting the use of IRIs and integers. This could easily be fixed in the grammar. · The grammar cannot unambiguously parse the ‘->’ operator in frames. Specifically, ‘-’ characters are allowed in PN_LOCAL names and hence a parser cannot determine if ‘status->’ is (‘status’ ‘->’) or (‘status-’ ‘>’). One way to fix this is to amend the PN_LOCAL production as follows: PN_LOCAL ::= ( PN_CHARS_U | [0-9] ) ((PN_CHARS|'.')* ((PN_CHARS)-('-')))? However, unilaterally changing the definition of this production, which is defined in the SPARQL Query Language for RDF specification, makes me uncomfortable. · I assume that the presentation syntax is case-sensitive. I couldn’t find this stated anywhere in the documentation, but function/predicate names do appear to be documented as being case-sensitive. · The EBNF does not specify whitespace handling. A couple of productions (RULE and ACTION_BLOCK) are crafted to enforce the use of whitespace. This is not necessary. It seems inconsistent with the rest of the specification and can cause parsing issues. In addition, the Const production exhibits whitespaces issues. The intention may have been to disallow the use of whitespace around ‘^^’, but any direct implementation of the EBNF will probably allow whitespace between ‘^^’ and the SYMSPACE. Of course, I am being a little nit-picking about all this. On the whole, the EBNF translated very smoothly and directly to ‘M’ (MGrammar) and proved to be fairly complete. I have encountered far worse issues when translating other EBNF specifications into usable grammars. I can’t imagine there would be any difficulty in implementing the same grammar in Antlr, COCO/R, gppg, XText, Bison, etc. A general observation, which repeats a point made above, is that the use of parenthesis in the presentation syntax can feel inconsistent and un-intuitive. It isn’t actually inconsistent, but I think the presentation syntax could be improved by adopting braces, rather than parenthesis, to delimit subordinate syntax elements in a similar way to so many programming languages. The familiarity of braces would communicate the structure of the syntax more clearly to people like me. If braces were adopted, parentheses could be retained around ‘var (frame | ‘new()’) constructs in action blocks. This use of parenthesis feels very LISP-like, and I think that this is my issue. It’s as if the presentation syntax represents the deformed love-child of LISP and C. In some places (specifically, action blocks), parenthesis is used in a LISP-like fashion. In other places it is used like braces in C. I find this quite confusing. Here is a corrected version of the running example (Example 9.1) in compliant presentation syntax: Document( Prefix( ex1 <http://example.com/2009/prd2> ) (* ex1:CheckoutRuleset *) Group rif:forwardChaining ( (* ex1:GoldRule *) Group 10 ( Forall ?customer such that And(?customer # ex1:Customer ?customer[ex1:status->"Silver"]) (Forall ?shoppingCart such that ?customer[ex1:shoppingCart->?shoppingCart] (If Exists ?value (And(?shoppingCart[ex1:value->?value] External(pred:numeric-greater-than-or-equal(?value 2000)))) Then Do(Modify(?customer[ex1:status->"Gold"]))))) (* ex1:DiscountRule *) Group ( Forall ?customer such that ?customer # ex1:Customer (If Or( ?customer[ex1:status->"Silver"] ?customer[ex1:status->"Gold"]) Then Do ((?s ?customer[ex1:shoppingCart-> ?s]) (?v ?s[ex1:value->?v]) Modify(?s [ex1:value->External(func:numeric-multiply (?v 0.95))])))) (* ex1:NewCustomerAndWidgetRule *) Group ( Forall ?customer such that And(?customer # ex1:Customer ?customer[ex1:status->"New"] ) (If Exists ?shoppingCart ?item (And(?customer[ex1:shoppingCart->?shoppingCart] ?shoppingCart[ex1:containsItem->?item] ?item # ex1:Widget ) ) Then Do( (?s ?customer[ex1:shoppingCart->?s]) (?val ?s[ex1:value->?val]) (?voucher ?customer[ex1:voucher->?voucher]) Retract(?customer[ex1:voucher->?voucher]) Retract(?voucher) Modify(?s[ex1:value->External(func:numeric-multiply(?val 0.90))])))) (* ex1:UnknownStatusRule *) Group ( Forall ?customer such that ?customer # ex1:Customer (If Not(Exists ?status (And(?customer[ex1:status->?status] External(pred:list-contains(List("New" "Bronze" "Silver" "Gold") ?status)) ))) Then Do( Execute(act:print(External(func:concat("New customer: " ?customer)))) Assert(?customer[ex1:status->"New"])))) ) ) I hope that helps someone out there :-)

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Benchmarking MySQL Replication with Multi-Threaded Slaves

- by Mat Keep

0 0 1 1145 6530 Homework 54 15 7660 14.0 Normal 0 false false false EN-US JA 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-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US;} The objective of this benchmark is to measure the performance improvement achieved when enabling the Multi-Threaded Slave enhancement delivered as a part MySQL 5.6. As the results demonstrate, Multi-Threaded Slaves delivers 5x higher replication performance based on a configuration with 10 databases/schemas. For real-world deployments, higher replication performance directly translates to: · Improved consistency of reads from slaves (i.e. reduced risk of reading "stale" data) · Reduced risk of data loss should the master fail before replicating all events in its binary log (binlog) The multi-threaded slave splits processing between worker threads based on schema, allowing updates to be applied in parallel, rather than sequentially. This delivers benefits to those workloads that isolate application data using databases - e.g. multi-tenant systems deployed in cloud environments. Multi-Threaded Slaves are just one of many enhancements to replication previewed as part of the MySQL 5.6 Development Release, which include: · Global Transaction Identifiers coupled with MySQL utilities for automatic failover / switchover and slave promotion · Crash Safe Slaves and Binlog · Optimized Row Based Replication · Replication Event Checksums · Time Delayed Replication These and many more are discussed in the “MySQL 5.6 Replication: Enabling the Next Generation of Web & Cloud Services” Developer Zone article Back to the benchmark - details are as follows. Environment The test environment consisted of two Linux servers: · one running the replication master · one running the replication slave. Only the slave was involved in the actual measurements, and was based on the following configuration: - Hardware: Oracle Sun Fire X4170 M2 Server - CPU: 2 sockets, 6 cores with hyper-threading, 2930 MHz. - OS: 64-bit Oracle Enterprise Linux 6.1 - Memory: 48 GB Test Procedure Initial Setup: Two MySQL servers were started on two different hosts, configured as replication master and slave. 10 sysbench schemas were created, each with a single table: CREATE TABLE `sbtest` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `k` int(10) unsigned NOT NULL DEFAULT '0', `c` char(120) NOT NULL DEFAULT '', `pad` char(60) NOT NULL DEFAULT '', PRIMARY KEY (`id`), KEY `k` (`k`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 10,000 rows were inserted in each of the 10 tables, for a total of 100,000 rows. When the inserts had replicated to the slave, the slave threads were stopped. The slave data directory was copied to a backup location and the slave threads position in the master binlog noted. 10 sysbench clients, each configured with 10 threads, were spawned at the same time to generate a random schema load against each of the 10 schemas on the master. Each sysbench client executed 10,000 "update key" statements: UPDATE sbtest set k=k+1 WHERE id = <random row> In total, this generated 100,000 update statements to later replicate during the test itself. Test Methodology: The number of slave workers to test with was configured using: SET GLOBAL slave_parallel_workers=<workers> Then the slave IO thread was started and the test waited for all the update queries to be copied over to the relay log on the slave. The benchmark clock was started and then the slave SQL thread was started. The test waited for the slave SQL thread to finish executing the 100k update queries, doing "select master_pos_wait()". When master_pos_wait() returned, the benchmark clock was stopped and the duration calculated. The calculated duration from the benchmark clock should be close to the time it took for the SQL thread to execute the 100,000 update queries. The 100k queries divided by this duration gave the benchmark metric, reported as Queries Per Second (QPS). Test Reset: The test-reset cycle was implemented as follows: · the slave was stopped · the slave data directory replaced with the previous backup · the slave restarted with the slave threads replication pointer repositioned to the point before the update queries in the binlog. The test could then be repeated with identical set of queries but a different number of slave worker threads, enabling a fair comparison. The Test-Reset cycle was repeated 3 times for 0-24 number of workers and the QPS metric calculated and averaged for each worker count. MySQL Configuration The relevant configuration settings used for MySQL are as follows: binlog-format=STATEMENT relay-log-info-repository=TABLE master-info-repository=TABLE As described in the test procedure, the slave_parallel_workers setting was modified as part of the test logic. The consequence of changing this setting is: 0 worker threads: - current (i.e. single threaded) sequential mode - 1 x IO thread and 1 x SQL thread - SQL thread both reads and executes the events 1 worker thread: - sequential mode - 1 x IO thread, 1 x Coordinator SQL thread and 1 x Worker thread - coordinator reads the event and hands it to the worker who executes 2+ worker threads: - parallel execution - 1 x IO thread, 1 x Coordinator SQL thread and 2+ Worker threads - coordinator reads events and hands them to the workers who execute them Results Figure 1 below shows that Multi-Threaded Slaves deliver ~5x higher replication performance when configured with 10 worker threads, with the load evenly distributed across our 10 x schemas. This result is compared to the current replication implementation which is based on a single SQL thread only (i.e. zero worker threads). Figure 1: 5x Higher Performance with Multi-Threaded Slaves The following figure shows more detailed results, with QPS sampled and reported as the worker threads are incremented. The raw numbers behind this graph are reported in the Appendix section of this post. Figure 2: Detailed Results As the results above show, the configuration does not scale noticably from 5 to 9 worker threads. When configured with 10 worker threads however, scalability increases significantly. The conclusion therefore is that it is desirable to configure the same number of worker threads as schemas. Other conclusions from the results: · Running with 1 worker compared to zero workers just introduces overhead without the benefit of parallel execution. · As expected, having more workers than schemas adds no visible benefit. Aside from what is shown in the results above, testing also demonstrated that the following settings had a very positive effect on slave performance: relay-log-info-repository=TABLE master-info-repository=TABLE For 5+ workers, it was up to 2.3 times as fast to run with TABLE compared to FILE. Conclusion As the results demonstrate, Multi-Threaded Slaves deliver significant performance increases to MySQL replication when handling multiple schemas. This, and the other replication enhancements introduced in MySQL 5.6 are fully available for you to download and evaluate now from the MySQL Developer site (select Development Release tab). You can learn more about MySQL 5.6 from the documentation Please don’t hesitate to comment on this or other replication blogs with feedback and questions. Appendix – Detailed Results

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A star algorithm implementation problems

- by bryan226

I’m having some trouble implementing the A* algorithm in a 2D tile based game. The problem is basically that the algorithm gets stuck when something gets in its direct way (e.g. walls) Note that it only allows Horizontal and Vertical movement. Here's a picture as it works fine across the map without something in its direct way: (Green tile = destination, Blue = In closed list, Green = in open list) This is what happens if I try to walk 'around' a wall: I calculate costs with the F = G + H formula: G = 1 Cost per Step H = 10 Cost per Step //Count how many tiles are between current-tile & destination-tile The functions: short c_astar::GuessH(short Startx,short Starty,short Destinationx,short Destinationy) { hgeVector Start, Destination; Start.x = Startx; Start.y = Starty; Destination.x = Destinationx; Destination.y = Destinationy; short a = 0; short b = 0; if(Start.x > Destination.x) a = Start.x - Destination.x; else a = Destination.x - Start.x; if(Start.y > Destination.y) b = Start.y - Destination.y; else b = Destination.y - Start.y; return (a+b)*10; } short c_astar::GuessG(short Startx,short Starty,short Currentx,short Currenty) { hgeVector Start, Destination; Start.x = Startx; Start.y = Starty; Destination.x = Currentx; Destination.y = Currenty; short a = 0; short b = 0; if(Start.x > Destination.x) a = Start.x - Destination.x; else a = Destination.x - Start.x; if(Start.y > Destination.y) b = Start.y - Destination.y; else b = Destination.y - Start.y; return (a+b); } At the end of the loop I check which tile is the cheapest to go according to its F value: Then some quick checks are done for each tile (UP,DOWN,LEFT,RIGHT): //...CX are holding the F value of the TILE specified // Info: C0 = Center (Current) // C1 = UP // C2 = DOWN // C3 = LEFT // C4 = RIGHT //Quick checks if(((C1 < C2) && (C1 < C3) && (C1 < C4))) { Current.y -= 1; bSimilar = false; if(DEBUG) hge->System_Log("C1 < ALL"); } //.. same for C2,C3 & C4 If there are multiple tiles with the same F value: It’s actually a switch for DOWNLEFT,UPRIGHT.. etc. Here’s one of it: case UPRIGHT: { //UP Temporary = Current; Temporary.y -= 1; bTileStatus[0] = IsTileWalkable(Temporary.x,Temporary.y); if(bTileStatus[0]) { //Proceed normal we are OK & walkable Tilex.Tile = map.at(Temporary.y).at(Temporary.x); //Search in lists if(SearchInClosedList(Tilex.Tile.ID,C0)) bFoundInClosedList[0] = true; if(SearchInOpenList(Tilex.Tile.ID,C0)) bFoundInOpenList[0] = true; //RIGHT Temporary = Current; Temporary.x += 1; bTileStatus[1] = IsTileWalkable(Temporary.x,Temporary.y); if(bTileStatus[1]) { //Proceed normal we are OK & walkable Tilex.Tile = map.at(Temporary.y).at(Temporary.x); //Search in lists if(SearchInClosedList(Tilex.Tile.ID,C0)) bFoundInClosedList[1] = true; if(SearchInOpenList(Tilex.Tile.ID,C0)) bFoundInOpenList[1] = true; //************************************************* // Purpose: ClosedList behavior //************************************************* if(bFoundInClosedList[0] && !bFoundInClosedList[1]) { //UP found in ClosedList. Go RIGHT return RIGHT; } if(!bFoundInClosedList[0] && bFoundInClosedList[1]) { //RIGHT found in ClosedList. Go UP return UP; } if(bFoundInClosedList[0] && bFoundInClosedList[1]) { //Both found in ClosedList. Random value switch(hge->Random_Int(8,9)) { case 8: return UP; break; case 9: return RIGHT; break; } } //************************************************* // Purpose: OpenList behavior //************************************************* if(bFoundInOpenList[0] && !bFoundInOpenList[1]) { //UP found in OpenList. Go RIGHT return RIGHT; } if(!bFoundInOpenList[0] && bFoundInOpenList[1]) { //RIGHT found in OpenList. Go UP return UP; } if(bFoundInOpenList[0] && bFoundInOpenList[1]) { //Both found in OpenList. Random value switch(hge->Random_Int(8,9)) { case 8: return UP; break; case 9: return RIGHT; break; } } } else if(!bTileStatus[1]) { //RIGHT is not walkable OR out of range //Choose UP return UP; } } else if(!bTileStatus[0]) { //UP is not walkable OR out of range //Fast check RIGHT Temporary = Current; Temporary.x += 1; bTileStatus[1] = IsTileWalkable(Temporary.x,Temporary.y); if(bTileStatus[1]) { return RIGHT; } else return FAILED; //Failed, no valid path found! } } break; A log for the second picture: (Cut down to ten passes, because it’s just repeating itself) ----------------------------------------------------- PASS: 1 | C1: 211 | C2: 191 | C3: 211 | C4: 191 DOWN + RIGHT SIMILAR Going DOWN ----------------------------------------------------- PASS: 2 | C1: 200 | C2: 182 | C3: 202 | C4: 182 DOWN + RIGHT SIMILAR Going DOWN ----------------------------------------------------- PASS: 3 | C1: 191 | C2: 193 | C3: 193 | C4: 173 C4 < ALL Tile(12.000000,6.000000) not walkable. MAX_F_VALUE set. ----------------------------------------------------- PASS: 4 | C1: 182 | C2: 184 | C3: 182 | C4: 999 UP + LEFT SIMILAR Going UP Tile(12.000000,5.000000) not walkable. MAX_F_VALUE set. ----------------------------------------------------- PASS: 5 | C1: 191 | C2: 173 | C3: 191 | C4: 999 C2 < ALL Tile(12.000000,6.000000) not walkable. MAX_F_VALUE set. ----------------------------------------------------- PASS: 6 | C1: 182 | C2: 184 | C3: 182 | C4: 999 UP + LEFT SIMILAR Going UP Tile(12.000000,5.000000) not walkable. MAX_F_VALUE set. ----------------------------------------------------- PASS: 7 | C1: 191 | C2: 173 | C3: 191 | C4: 999 C2 < ALL Tile(12.000000,6.000000) not walkable. MAX_F_VALUE set. ----------------------------------------------------- PASS: 8 | C1: 182 | C2: 184 | C3: 182 | C4: 999 UP + LEFT SIMILAR Going LEFT ----------------------------------------------------- PASS: 9 | C1: 191 | C2: 193 | C3: 193 | C4: 173 C4 < ALL Tile(12.000000,6.000000) not walkable. MAX_F_VALUE set. ----------------------------------------------------- PASS: 10 | C1: 182 | C2: 184 | C3: 182 | C4: 999 UP + LEFT SIMILAR Going LEFT ----------------------------------------------------- Its always going after the cheapest F value, which seems to be wrong. If someone could point me to the right direction I'd be thankful. Regards, bryan226

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Community Outreach - Where Should I Go

- by Roger Brinkley

A few days ago I was talking to person new to community development and they asked me what guidelines I used to determine the worthiness of a particular event. After our conversation was over I thought about it a little bit more and figured out there are three ways to determine if any event (be it conference, blog, podcast or other social medias) is worth doing: Transferability, Multiplication, and Impact. Transferability - Is what I have to say useful to the people that are going to hear it. For instance, consider a company that has product offering that can connect up using a number of languages like Scala, Grovey or Java. Sending a Scala expert to talk about Scala and the product is not transferable to a Java User Group, but a Java expert doing the same talk with a Java slant is. Similarly, talking about JavaFX to any Java User Group meeting in Brazil was pretty much a wasted effort until it was open sourced. Once it was open sourced it was well received. You can also look at transferability in relation to the subject matter that you're dealing with. How transferable is a presentation that I create. Can I, or a technical writer on the staff, turn it into some technical document. Could it be converted into some type of screen cast. If we have a regular podcast can we make a reference to the document, catch the high points or turn it into a interview. Is there a way of using this in the sales group. In other words is the document purely one dimensional or can it be re-purposed in other forms. Multiplication - On every trip I'm looking for 2 to 5 solid connections that I can make with developers. These are long term connections, because I know that once that relationship is established it will lead to another 2 - 5 from that connection and within a couple of years were talking about some 100 connections from just one developer. For instance, when I was working on JavaHelp in 2000 I hired a science teacher with a programming background. We've developed a very tight relationship over the year though we rarely see each other more than once a year. But at this JavaOne, one of his employees came up to me and said, "Richard (Rick Hard in Czech) told me to tell you that he couldn't make it to JavaOne this year but if I saw you to tell you hi". Another example is from my Mobile & Embedded days in Brasil. On our very first FISL trip about 5 years ago there were two university students that had created a project called "Marge". Marge was a Bluetooth framework that made connecting bluetooth devices easier. I invited them to a "Sun" dinner that evening. Originally they were planning on leaving that afternoon, but they changed their plans recognizing the opportunity. Their eyes were as big a saucers when they realized the level of engineers at the meeting. They went home started a JUG in Florianoplis that we've visited more than a couple of times. One of them went to work for Brazilian government lab like Berkley Labs, MIT Lab, John Hopkins Applied Physicas Labs or Lincoln Labs in the US. That presented us with an opportunity to show Embedded Java as a possibility for some of the work they were doing there. Impact - The final criteria is how life changing is what I'm going to say be to the individuals I'm reaching. A t-shirt is just a token, but when I reach down and tug at their developer hearts then I know I've succeeded. I'll never forget one time we flew all night to reach Joan Pasoa in Northern Brazil. We arrived at 2am went immediately to our hotel only to be woken up at 6 am to travel 2 hours by car to the presentation hall. When we arrived we were totally exhausted. Outside the facility there were 500 people lined up to hear 6 speakers for the day. That itself was uplifting. I delivered one of my favorite talks on "I have passion". It was a talk on golf and embedded java development, "Find your passion". When we finished a couple of first year students came up to me and said how much my talk had inspired them. FISL is another great example. I had been about 4 years in a row. FISL is a very young group of developers so capturing their attention is important. Several of the students will come back 2 or 3 years later and ask me questions about research or jobs. And then there's Louis. Louis is one my favorite Brazilians. I can only describe him as a big Brazilian teddy bear. I see him every year at FISL. He works primarily in Java EE but he's attended every single one of my talks over the last 4 years. I can't tell you why, but he always greets me and gives me a hug. For some reason I've had a real impact. And of course when it comes to impact you don't just measure a presentation but every single interaction you have at an event. It's the hall way conversations, the booth conversations, but more importantly it's the conversations at dinner tables or in the cars when you're getting transported to an event. There's a good story that illustrates this. Last year in the spring I was traveling to Goiânia in Brazil. I've been there many times and leaders there no me well. One young man has picked me up at the airport on more than one occasion. We were going out to dinner one evening and he brought his girl friend along. One thing let to another and I eventually asked him, in front of her, "Why haven't you asked her to marry you?" There were all kinds of excuses and she just looked at him and smiled. When I came back in December for JavaOne he came and sought me. "I just want to tell you that I thought a lot about what you said, and I asked her to marry me. We're getting married next Spring." Sometimes just one presentation is all it takes to make an impact. Other times it takes years. Some impacts are directly related to the company and some are more personal in nature. It doesn't matter which it is because it's having the impact that matters.

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How to Recover From a Virus Infection: 3 Things You Need to Do

- by Chris Hoffman

If your computer becomes infected with a virus or another piece of malware, removing the malware from your computer is only the first step. There’s more you need to do to ensure you’re secure. Note that not every antivirus alert is an actual infection. If your antivirus program catches a virus before it ever gets a chance to run on your computer, you’re safe. If it catches the malware later, you have a bigger problem. Change Your Passwords You’ve probably used your computer to log into your email, online banking websites, and other important accounts. Assuming you had malware on your computer, the malware could have logged your passwords and uploaded them to a malicious third party. With just your email account, the third party could reset your passwords on other websites and gain access to almost any of your online accounts. To prevent this, you’ll want to change the passwords for your important accounts — email, online banking, and whatever other important accounts you’ve logged into from the infected computer. You should probably use another computer that you know is clean to change the passwords, just to be safe. When changing your passwords, consider using a password manager to keep track of strong, unique passwords and two-factor authentication to prevent people from logging into your important accounts even if they know your password. This will help protect you in the future. Ensure the Malware Is Actually Removed Once malware gets access to your computer and starts running, it has the ability to do many more nasty things to your computer. For example, some malware may install rootkit software and attempt to hide itself from the system. Many types of Trojans also “open the floodgates” after they’re running, downloading many different types of malware from malicious web servers to the local system. In other words, if your computer was infected, you’ll want to take extra precautions. You shouldn’t assume it’s clean just because your antivirus removed what it found. It’s probably a good idea to scan your computer with multiple antivirus products to ensure maximum detection. You may also want to run a bootable antivirus program, which runs outside of Windows. Such bootable antivirus programs will be able to detect rootkits that hide themselves from Windows and even the software running within Windows. avast! offers the ability to quickly create a bootable CD or USB drive for scanning, as do many other antivirus programs. You may also want to reinstall Windows (or use the Refresh feature on Windows 8) to get your computer back to a clean state. This is more time-consuming, especially if you don’t have good backups and can’t get back up and running quickly, but this is the only way you can have 100% confidence that your Windows system isn’t infected. It’s all a matter of how paranoid you want to be. Figure Out How the Malware Arrived If your computer became infected, the malware must have arrived somehow. You’ll want to examine your computer’s security and your habits to prevent more malware from slipping through in the same way. Windows is complex. For example, there are over 50 different types of potentially dangerous file extensions that can contain malware to keep track of. We’ve tried to cover many of the most important security practices you should be following, but here are some of the more important questions to ask: Are you using an antivirus? – If you don’t have an antivirus installed, you should. If you have Microsoft Security Essentials (known as Windows Defender on Windows 8), you may want to switch to a different antivirus like the free version of avast!. Microsoft’s antivirus product has been doing very poorly in tests. Do you have Java installed? – Java is a huge source of security problems. The majority of computers on the Internet have an out-of-date, vulnerable version of Java installed, which would allow malicious websites to install malware on your computer. If you have Java installed, uninstall it. If you actually need Java for something (like Minecraft), at least disable the Java browser plugin. If you’re not sure whether you need Java, you probably don’t. Are any browser plugins out-of-date? – Visit Mozilla’s Plugin Check website (yes, it also works in other browsers, not just Firefox) and see if you have any critically vulnerable plugins installed. If you do, ensure you update them — or uninstall them. You probably don’t need older plugins like QuickTime or RealPlayer installed on your computer, although Flash is still widely used. Are your web browser and operating system set to automatically update? – You should be installing updates for Windows via Windows Update when they appear. Modern web browsers are set to automatically update, so they should be fine — unless you went out of your way to disable automatic updates. Using out-of-date web browsers and Windows versions is dangerous. Are you being careful about what you run? – Watch out when downloading software to ensure you don’t accidentally click sketchy advertisements and download harmful software. Avoid pirated software that may be full of malware. Don’t run programs from email attachments. Be careful about what you run and where you get it from in general. If you can’t figure out how the malware arrived because everything looks okay, there’s not much more you can do. Just try to follow proper security practices. You may also want to keep an extra-close eye on your credit card statement for a while if you did any online-shopping recently. As so much malware is now related to organized crime, credit card numbers are a popular target.

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Integration Patterns with Azure Service Bus Relay, Part 3: Anonymous partial-trust consumer

- by Elton Stoneman

This is the third in the IPASBR series, see also: Integration Patterns with Azure Service Bus Relay, Part 1: Exposing the on-premise service Integration Patterns with Azure Service Bus Relay, Part 2: Anonymous full-trust .NET consumer As the patterns get further from the simple .NET full-trust consumer, all that changes is the communication protocol and the authentication mechanism. In Part 3 the scenario is that we still have a secure .NET environment consuming our service, so we can store shared keys securely, but the runtime environment is locked down so we can't use Microsoft.ServiceBus to get the nice WCF relay bindings. To support this we will expose a RESTful endpoint through the Azure Service Bus, and require the consumer to send a security token with each HTTP service request. Pattern applicability This is a good fit for scenarios where: the runtime environment is secure enough to keep shared secrets the consumer can execute custom code, including building HTTP requests with custom headers the consumer cannot use the Azure SDK assemblies the service may need to know who is consuming it the service does not need to know who the end-user is Note there isn't actually a .NET requirement here. By exposing the service in a REST endpoint, anything that can talk HTTP can be a consumer. We'll authenticate through ACS which also gives us REST endpoints, so the service is still accessed securely. Our real-world example would be a hosted cloud app, where we we have enough room in the app's customisation to keep the shared secret somewhere safe and to hook in some HTTP calls. We will be flowing an identity through to the on-premise service now, but it will be the service identity given to the consuming app - the end user's identity isn't flown through yet. In this post, we’ll consume the service from Part 1 in ASP.NET using the WebHttpRelayBinding. The code for Part 3 (+ Part 1) is on GitHub here: IPASBR Part 3. Authenticating and authorizing with ACS We'll follow the previous examples and add a new service identity for the namespace in ACS, so we can separate permissions for different consumers (see walkthrough in Part 1). I've named the identity partialTrustConsumer. We’ll be authenticating against ACS with an explicit HTTP call, so we need a password credential rather than a symmetric key – for a nice secure option, generate a symmetric key, copy to the clipboard, then change type to password and paste in the key: We then need to do the same as in Part 2 , add a rule to map the incoming identity claim to an outgoing authorization claim that allows the identity to send messages to Service Bus: Issuer: Access Control Service Input claim type: http://schemas.xmlsoap.org/ws/2005/05/identity/claims/nameidentifier Input claim value: partialTrustConsumer Output claim type: net.windows.servicebus.action Output claim value: Send As with Part 2, this sets up a service identity which can send messages into Service Bus, but cannot register itself as a listener, or manage the namespace. RESTfully exposing the on-premise service through Azure Service Bus Relay The part 3 sample code is ready to go, just put your Azure details into Solution Items\AzureConnectionDetails.xml and “Run Custom Tool” on the .tt files. But to do it yourself is very simple. We already have a WebGet attribute in the service for locally making REST calls, so we are just going to add a new endpoint which uses the WebHttpRelayBinding to relay that service through Azure. It's as easy as adding this endpoint to Web.config for the service: <endpoint address="https://sixeyed-ipasbr.servicebus.windows.net/rest" binding="webHttpRelayBinding" contract="Sixeyed.Ipasbr.Services.IFormatService" behaviorConfiguration="SharedSecret"> </endpoint> - and adding the webHttp attribute in your endpoint behavior: <behavior name="SharedSecret"> <webHttp/> <transportClientEndpointBehavior credentialType="SharedSecret"> <clientCredentials> <sharedSecret issuerName="serviceProvider" issuerSecret="gl0xaVmlebKKJUAnpripKhr8YnLf9Neaf6LR53N8uGs="/> </clientCredentials> </transportClientEndpointBehavior> </behavior> Where's my WSDL? The metadata story for REST is a bit less automated. In our local webHttp endpoint we've enabled WCF's built-in help, so if you navigate to: http://localhost/Sixeyed.Ipasbr.Services/FormatService.svc/rest/help - you'll see the uri format for making a GET request to the service. The format is the same over Azure, so this is where you'll be connecting: https://[your-namespace].servicebus.windows.net/rest/reverse?string=abc123 Build the service with the new endpoint, open that in a browser and you'll get an XML version of an HTTP status code - a 401 with an error message stating that you haven’t provided an authorization header: <?xml version="1.0"?><Error><Code>401</Code><Detail>MissingToken: The request contains no authorization header..TrackingId:4cb53408-646b-4163-87b9-bc2b20cdfb75_5,TimeStamp:10/3/2012 8:34:07 PM</Detail></Error> By default, the setup of your Service Bus endpoint as a relying party in ACS expects a Simple Web Token to be presented with each service request, and in the browser we're not passing one, so we can't access the service. Note that this request doesn't get anywhere near your on-premise service, Service Bus only relays requests once they've got the necessary approval from ACS. Why didn't the consumer need to get ACS authorization in Part 2? It did, but it was all done behind the scenes in the NetTcpRelayBinding. By specifying our Shared Secret credentials in the consumer, the service call is preceded by a check on ACS to see that the identity provided is a) valid, and b) allowed access to our Service Bus endpoint. By making manual HTTP requests, we need to take care of that ACS check ourselves now. We do that with a simple WebClient call to the ACS endpoint of our service; passing the shared secret credentials, we will get back an SWT: var values = new System.Collections.Specialized.NameValueCollection(); values.Add("wrap_name", "partialTrustConsumer"); //service identity name values.Add("wrap_password", "suCei7AzdXY9toVH+S47C4TVyXO/UUFzu0zZiSCp64Y="); //service identity password values.Add("wrap_scope", "http://sixeyed-ipasbr.servicebus.windows.net/"); //this is the realm of the RP in ACS var acsClient = new WebClient(); var responseBytes = acsClient.UploadValues("https://sixeyed-ipasbr-sb.accesscontrol.windows.net/WRAPv0.9/", "POST", values); rawToken = System.Text.Encoding.UTF8.GetString(responseBytes); With a little manipulation, we then attach the SWT to subsequent REST calls in the authorization header; the token contains the Send claim returned from ACS, so we will be authorized to send messages into Service Bus. Running the sample Navigate to http://localhost:2028/Sixeyed.Ipasbr.WebHttpClient/Default.cshtml, enter a string and hit Go! - your string will be reversed by your on-premise service, routed through Azure: Using shared secret client credentials in this way means ACS is the identity provider for your service, and the claim which allows Send access to Service Bus is consumed by Service Bus. None of the authentication details make it through to your service, so your service is not aware who the consumer is (MSDN calls this "anonymous authentication").

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Oracle Enterprise Manager Ops Center : Using Operational Profiles to Install Packages and other Content

- by LeonShaner

Oracle Enterprise Manager Ops Center provides numerous ways to deploy content, such as through OS Update Profiles, or as part of an OS Provisioning plan or combinations of those and other "Install Software" capabilities of Deployment Plans. This short "how-to" blog will highlight an alternative way to deploy content using Operational Profiles. Usually we think of Operational Profiles as a way to execute a simple "one-time" script to perform a basic system administration function, which can optionally be based on user input; however, Operational Profiles can be much more powerful than that. There is often more to performing an action than merely running a script -- sometimes configuration files, packages, binaries, and other scripts, etc. are needed to perform the action, and sometimes the user would like to leave such content on the system for later use. For shell scripts and other content written to be generic enough to work on any flavor of UNIX, converting the same scripts and configuration files into Solaris 10 SVR4 package, Solaris 11 IPS package, and/or a Linux RPM's might be seen as three times the work, for little appreciable gain. That is where using an Operational Profile to deploy simple scripts and other generic content can be very helpful. The approach is so powerful, that pretty much any kind of content can be deployed using an Operational Profile, provided the files involved are not overly large, and it is not necessary to convert the content into UNIX variant-specific formats. The basic formula for deploying content with an Operational Profile is as follows: Begin with a traditional script header, which is a UNIX shell script that will be responsible for decoding and extracting content, copying files into the right places, and executing any other scripts and commands needed to install and configure that content. Include steps to make the script platform-aware, to do the right thing for a given UNIX variant, or a "sorry" message if the operator has somehow tried to run the Operational Profile on a system where the script is not designed to run. Ops Center can constrain execution by target type, so such checks at this level are an added safeguard, but also useful with the generic target type of "Operating System" where the admin wants the script to "do the right thing," whatever the UNIX variant. Include helpful output to show script progress, and any other informational messages that can help the admin determine what has gone wrong in the case of a problem in script execution. Such messages will be shown in the job execution log. Include necessary "clean up" steps for normal and error exit conditions Set non-zero exit codes when appropriate -- a non-zero exit code will cause an Operational Profile job to be marked failed, which is the admin's cue to look into the job details for diagnostic messages in the output from the script. That first bullet deserves some explanation. If Operational Profiles are usually simple "one-time" scripts and binary content is not allowed, then how does the actual content, packages, binaries, and other scripts get delivered along with the script? More specifically, how does one include such content without needing to first create some kind of traditional package? All that is required is to simply encode the content and append it to the end of the Operational Profile. The header portion of the Operational Profile will need to contain the commands to decode the embedded content that has been appended to the bottom of the script. The header code can do whatever else is needed, and finally clean up any intermediate files that were created during the decoding and extraction of the content. One way to encode binary and other content for inclusion in a script is to use the "uuencode" utility to convert the content into simple base64 ASCII text -- a form that is suitable to be appended to an Operational Profile. The behavior of the "uudecode" utility is such that it will skip over any parts of the input that do not fit the uuencoded "begin" and "end" clauses. For that reason, your header script will be skipped over, and uudecode will find your embedded content, that you will uuencode and paste at the end of the Operational Profile. You can have as many "begin" / "end" clauses as you need -- just separate each embedded file by an empty line between "begin" and "end" clauses. Example: Install SUNWsneep and set the system serial number Script: deploySUNWsneep.sh ( <- right-click / save to download) Highlights: #!/bin/sh # Required variables: OC_SERIAL="$OC_SERIAL" # The user-supplied serial number for the asset ... Above is a good practice, showing right up front what kind of input the Operational Profile will require. The right-hand side where $OC_SERIAL appears in this example will be filled in by Ops Center based on the user input at deployment time. The script goes on to restrict the use of the program to the intended OS type (Solaris 10 or older, in this example, but other content might be suitable for Solaris 11, or Linux -- it depends on the content and the script that will handle it). A temporary working directory is created, and then we have the command that decodes the embedded content from "self" which in scripting terms is $0 (a variable that expands to the name of the currently executing script): # Pass myself through uudecode, which will extract content to the current dir uudecode $0 At that point, whatever content was appended in uuencoded form at the end of the script has been written out to the current directory. In this example that yields a file, SUNWsneep.7.0.zip, which the rest of the script proceeds to unzip, and pkgadd, followed by running "/opt/SUNWsneep/bin/sneep -s $OC_SERIAL" which is the command that stores the system serial for future use by other programs such as Explorer. Don't get hung up on the example having used a pkgadd command. The content started as a zip file and it could have been a tar.gz, or any other file. This approach simply decodes the file. The header portion of the script has to make sense of the file and do the right thing (e.g. it's up to you). The script goes on to clean up after itself, whether or not the above was successful. Errors are echo'd by the script and a non-zero exit code is set where appropriate. Second to last, we have: # just in case, exit explicitly, so that uuencoded content will not cause error OPCleanUP exit # The rest of the script is ignored, except by uudecode # # UUencoded content follows # # e.g. for each file needed, # $ uuencode -m {source} {source} > {target}.uu5 # then paste the {target}.uu5 files below # they will be extracted into the workding dir at $TDIR # The commentary above also describes how to encode the content. Finally we have the uuencoded content: begin-base64 444 SUNWsneep.7.0.zip UEsDBBQAAAAIAPsRy0Di3vnukAAAAMcAAAAKABUAcmVhZG1lLnR4dFVUCQADOqnVT7up ... VXgAAFBLBQYAAAAAAgACAJEAAADTNwEAAAA= ==== That last line of "====" is the base64 uuencode equivalent of a blank line, followed by "end" and as mentioned you can have as many begin/end clauses as you need. Just separate each embedded file by a blank line after each ==== and before each begin-base64. Deploying the example Operational Profile looks like this (where I have pasted the system serial number into the required field): The job succeeded, but here is an example of the kind of diagnostic messages that the example script produces, and how Ops Center displays them in the job details: This same general approach could be used to deploy Explorer, and other useful utilities and scripts. Please let us know what you think? Until next time...\Leon-- Leon Shaner | Senior IT/Product ArchitectSystems Management | Ops Center Engineering @ Oracle The views expressed on this [blog; Web site] are my own and do not necessarily reflect the views of Oracle. 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HTG Explains: Why Does Rebooting a Computer Fix So Many Problems?

- by Chris Hoffman

Ask a geek how to fix a problem you’ve having with your Windows computer and they’ll likely ask “Have you tried rebooting it?” This seems like a flippant response, but rebooting a computer can actually solve many problems. So what’s going on here? Why does resetting a device or restarting a program fix so many problems? And why don’t geeks try to identify and fix problems rather than use the blunt hammer of “reset it”? This Isn’t Just About Windows Bear in mind that this soltion isn’t just limited to Windows computers, but applies to all types of computing devices. You’ll find the advice “try resetting it” applied to wireless routers, iPads, Android phones, and more. This same advice even applies to software — is Firefox acting slow and consuming a lot of memory? Try closing it and reopening it! Some Problems Require a Restart To illustrate why rebooting can fix so many problems, let’s take a look at the ultimate software problem a Windows computer can face: Windows halts, showing a blue screen of death. The blue screen was caused by a low-level error, likely a problem with a hardware driver or a hardware malfunction. Windows reaches a state where it doesn’t know how to recover, so it halts, shows a blue-screen of death, gathers information about the problem, and automatically restarts the computer for you . This restart fixes the blue screen of death. Windows has gotten better at dealing with errors — for example, if your graphics driver crashes, Windows XP would have frozen. In Windows Vista and newer versions of Windows, the Windows desktop will lose its fancy graphical effects for a few moments before regaining them. Behind the scenes, Windows is restarting the malfunctioning graphics driver. But why doesn’t Windows simply fix the problem rather than restarting the driver or the computer itself? Well, because it can’t — the code has encountered a problem and stopped working completely, so there’s no way for it to continue. By restarting, the code can start from square one and hopefully it won’t encounter the same problem again. Examples of Restarting Fixing Problems While certain problems require a complete restart because the operating system or a hardware driver has stopped working, not every problem does. Some problems may be fixable without a restart, though a restart may be the easiest option. Windows is Slow: Let’s say Windows is running very slowly. It’s possible that a misbehaving program is using 99% CPU and draining the computer’s resources. A geek could head to the task manager and look around, hoping to locate the misbehaving process an end it. If an average user encountered this same problem, they could simply reboot their computer to fix it rather than dig through their running processes. Firefox or Another Program is Using Too Much Memory: In the past, Firefox has been the poster child for memory leaks on average PCs. Over time, Firefox would often consume more and more memory, getting larger and larger and slowing down. Closing Firefox will cause it to relinquish all of its memory. When it starts again, it will start from a clean state without any leaked memory. This doesn’t just apply to Firefox, but applies to any software with memory leaks. Internet or Wi-Fi Network Problems: If you have a problem with your Wi-Fi or Internet connection, the software on your router or modem may have encountered a problem. Resetting the router — just by unplugging it from its power socket and then plugging it back in — is a common solution for connection problems. In all cases, a restart wipes away the current state of the software . Any code that’s stuck in a misbehaving state will be swept away, too. When you restart, the computer or device will bring the system up from scratch, restarting all the software from square one so it will work just as well as it was working before. “Soft Resets” vs. “Hard Resets” In the mobile device world, there are two types of “resets” you can perform. A “soft reset” is simply restarting a device normally — turning it off and then on again. A “hard reset” is resetting its software state back to its factory default state. When you think about it, both types of resets fix problems for a similar reason. For example, let’s say your Windows computer refuses to boot or becomes completely infected with malware. Simply restarting the computer won’t fix the problem, as the problem is with the files on the computer’s hard drive — it has corrupted files or malware that loads at startup on its hard drive. However, reinstalling Windows (performing a “Refresh or Reset your PC” operation in Windows 8 terms) will wipe away everything on the computer’s hard drive, restoring it to its formerly clean state. This is simpler than looking through the computer’s hard drive, trying to identify the exact reason for the problems or trying to ensure you’ve obliterated every last trace of malware. It’s much faster to simply start over from a known-good, clean state instead of trying to locate every possible problem and fix it. Ultimately, the answer is that “resetting a computer wipes away the current state of the software, including any problems that have developed, and allows it to start over from square one.” It’s easier and faster to start from a clean state than identify and fix any problems that may be occurring — in fact, in some cases, it may be impossible to fix problems without beginning from that clean state. Image Credit: Arria Belli on Flickr, DeclanTM on Flickr

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PostSharp, Obfuscation, and IL

- by Simon Cooper

Aspect-oriented programming (AOP) is a relatively new programming paradigm. Originating at Xerox PARC in 1994, the paradigm was first made available for general-purpose development as an extension to Java in 2001. From there, it has quickly been adapted for use in all the common languages used today. In the .NET world, one of the primary AOP toolkits is PostSharp. Attributes and AOP Normally, attributes in .NET are entirely a metadata construct. Apart from a few special attributes in the .NET framework, they have no effect whatsoever on how a class or method executes within the CLR. Only by using reflection at runtime can you access any attributes declared on a type or type member. PostSharp changes this. By declaring a custom attribute that derives from PostSharp.Aspects.Aspect, applying it to types and type members, and running the resulting assembly through the PostSharp postprocessor, you can essentially declare 'clever' attributes that change the behaviour of whatever the aspect has been applied to at runtime. A simple example of this is logging. By declaring a TraceAttribute that derives from OnMethodBoundaryAspect, you can automatically log when a method has been executed: public class TraceAttribute : PostSharp.Aspects.OnMethodBoundaryAspect { public override void OnEntry(MethodExecutionArgs args) { MethodBase method = args.Method; System.Diagnostics.Trace.WriteLine( String.Format( "Entering {0}.{1}.", method.DeclaringType.FullName, method.Name)); } public override void OnExit(MethodExecutionArgs args) { MethodBase method = args.Method; System.Diagnostics.Trace.WriteLine( String.Format( "Leaving {0}.{1}.", method.DeclaringType.FullName, method.Name)); } } [Trace] public void MethodToLog() { ... } Now, whenever MethodToLog is executed, the aspect will automatically log entry and exit, without having to add the logging code to MethodToLog itself. PostSharp Performance Now this does introduce a performance overhead - as you can see, the aspect allows access to the MethodBase of the method the aspect has been applied to. If you were limited to C#, you would be forced to retrieve each MethodBase instance using Type.GetMethod(), matching on the method name and signature. This is slow. Fortunately, PostSharp is not limited to C#. It can use any instruction available in IL. And in IL, you can do some very neat things. Ldtoken C# allows you to get the Type object corresponding to a specific type name using the typeof operator: Type t = typeof(Random); The C# compiler compiles this operator to the following IL: ldtoken [mscorlib]System.Random call class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle( valuetype [mscorlib]System.RuntimeTypeHandle) The ldtoken instruction obtains a special handle to a type called a RuntimeTypeHandle, and from that, the Type object can be obtained using GetTypeFromHandle. These are both relatively fast operations - no string lookup is required, only direct assembly and CLR constructs are used. However, a little-known feature is that ldtoken is not just limited to types; it can also get information on methods and fields, encapsulated in a RuntimeMethodHandle or RuntimeFieldHandle: // get a MethodBase for String.EndsWith(string) ldtoken method instance bool [mscorlib]System.String::EndsWith(string) call class [mscorlib]System.Reflection.MethodBase [mscorlib]System.Reflection.MethodBase::GetMethodFromHandle( valuetype [mscorlib]System.RuntimeMethodHandle) // get a FieldInfo for the String.Empty field ldtoken field string [mscorlib]System.String::Empty call class [mscorlib]System.Reflection.FieldInfo [mscorlib]System.Reflection.FieldInfo::GetFieldFromHandle( valuetype [mscorlib]System.RuntimeFieldHandle) These usages of ldtoken aren't usable from C# or VB, and aren't likely to be added anytime soon (Eric Lippert's done a blog post on the possibility of adding infoof, methodof or fieldof operators to C#). However, PostSharp deals directly with IL, and so can use ldtoken to get MethodBase objects quickly and cheaply, without having to resort to string lookups. The kicker However, there are problems. Because ldtoken for methods or fields isn't accessible from C# or VB, it hasn't been as well-tested as ldtoken for types. This has resulted in various obscure bugs in most versions of the CLR when dealing with ldtoken and methods, and specifically, generic methods and methods of generic types. This means that PostSharp was behaving incorrectly, or just plain crashing, when aspects were applied to methods that were generic in some way. So, PostSharp has to work around this. Without using the metadata tokens directly, the only way to get the MethodBase of generic methods is to use reflection: Type.GetMethod(), passing in the method name as a string along with information on the signature. Now, this works fine. It's slower than using ldtoken directly, but it works, and this only has to be done for generic methods. Unfortunately, this poses problems when the assembly is obfuscated. PostSharp and Obfuscation When using ldtoken, obfuscators don't affect how PostSharp operates. Because the ldtoken instruction directly references the type, method or field within the assembly, it is unaffected if the name of the object is changed by an obfuscator. However, the indirect loading used for generic methods was breaking, because that uses the name of the method when the assembly is put through the PostSharp postprocessor to lookup the MethodBase at runtime. If the name then changes, PostSharp can't find it anymore, and the assembly breaks. So, PostSharp needs to know about any changes an obfuscator does to an assembly. The way PostSharp does this is by adding another layer of indirection. When PostSharp obfuscation support is enabled, it includes an extra 'name table' resource in the assembly, consisting of a series of method & type names. When PostSharp needs to lookup a method using reflection, instead of encoding the method name directly, it looks up the method name at a fixed offset inside that name table: MethodBase genericMethod = typeof(ContainingClass).GetMethod(GetNameAtIndex(22)); PostSharp.NameTable resource: ... 20: get_Prop1 21: set_Prop1 22: DoFoo 23: GetWibble When the assembly is later processed by an obfuscator, the obfuscator can replace all the method and type names within the name table with their new name. That way, the reflection lookups performed by PostSharp will now use the new names, and everything will work as expected: MethodBase genericMethod = typeof(#kGy).GetMethod(GetNameAtIndex(22)); PostSharp.NameTable resource: ... 20: #kkA 21: #zAb 22: #EF5a 23: #2tg As you can see, this requires direct support by an obfuscator in order to perform these rewrites. Dotfuscator supports it, and now, starting with SmartAssembly 6.6.4, SmartAssembly does too. So, a relatively simple solution to a tricky problem, with some CLR bugs thrown in for good measure. You don't see those every day!

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Orchestrating the Virtual Enterprise

- by John Murphy

During the American Industrial Revolution, the Ford Motor Company did it all. It turned raw materials into a showroom full of Model Ts. It owned a steel mill, a glass factory, and an automobile assembly line. The company was both self-sufficient and innovative and went on to become one of the largest and most profitable companies in the world. Nowadays, it's unusual for any business to follow this vertical integration model because its much harder to be best in class across such a wide a range of capabilities and services. Instead, businesses focus on their core competencies and outsource other business functions to specialized suppliers. They exchange vertical integration for collaboration. When done well, all parties benefit from this arrangement and the collaboration leads to the creation of an agile, lean and successful "virtual enterprise." Case in point: For Sun hardware, Oracle outsources most of its manufacturing and all of its logistics to third parties. These are vital activities, but ones where Oracle doesn't have a core competency, so we shift them to business partners who do. Within our enterprise, we always retain the core functions of product development, support, and most of the sales function, because that's what constitutes our core value to our customers. This is a perfect example of a virtual enterprise. What are the implications of this? It means that we must exchange direct internal control for indirect external collaboration. This fundamentally changes the relative importance of different business processes, the boundaries of security and information sharing, and the relationship of the supply chain systems to the ERP. The challenge is that the systems required to support this virtual paradigm are still mired in "island enterprise" thinking. But help is at hand. Developments such as the Web, social networks, collaboration, and rules-based orchestration offer great potential to fundamentally re-architect supply chain systems to better support the virtual enterprise. Supply Chain Management Systems in a Virtual Enterprise Historically enterprise software was constructed to automate the ERP - and then the supply chain systems extended the ERP. They were joined at the hip. In virtual enterprises, the supply chain system needs to be ERP agnostic, sitting above each of the ERPs that are distributed across the virtual enterprise - most of which are operating in other businesses. This is vital so that the supply chain system can manage the flow of material and the related information through the multiple enterprises. It has to have strong collaboration tools. It needs to be highly flexible. Users need to be able to see information that's coming from multiple sources and be able to react and respond to events across those sources. Oracle Fusion Distributed Order Orchestration (DOO) is a perfect example of a supply chain system designed to operate in this virtual way. DOO embraces the idea that a company's fulfillment challenge is a distributed, multi-enterprise problem. It enables users to manage the process and the trading partners in a uniform way and deliver a consistent user experience while operating over a heterogeneous, virtual enterprise. This is a fundamental shift at the core of managing supply chains. It forces virtual enterprises to think architecturally about how best to construct their supply chain systems. Case in point, almost everyone has ordered from Amazon.com at one time or another. Our orders are as likely to be fulfilled by third parties as they are by Amazon itself. To deliver the order promptly and efficiently, Amazon has to send it to the right fulfillment location and know the availability in that location. It needs to be able to track status of the fulfillment and deal with exceptions. As a virtual enterprise, Amazon's operations, using thousands of trading partners, requires a very different approach to fulfillment than the traditional 'take an order and ship it from your own warehouse' model. Amazon had no choice but to develop a complex, expensive and custom solution to tackle this problem as there used to be no product solution available. Now, other companies who want to follow similar models have a better off-the-shelf choice -- Oracle Distributed Order Orchestration (DOO). Consider how another of our customers is using our distributed orchestration solution. This major airplane manufacturer has a highly complex business and interacts regularly with the U.S. Government and major airlines. It sits in the middle of an intricate supply chain and needed to improve visibility across its many different entities. Oracle Fusion DOO gives the company an orchestration mechanism so it could improve quality, speed, flexibility, and consistency without requiring an organ transplant of these highly complex legacy systems. Many retailers face the challenge of dealing with brick and mortar, Web, and reseller channels. They all need to be knitted together into a virtual enterprise experience that is consistent for their customers. When a large U.K. grocer with a strong brick and mortar retail operation added an online business, they turned to Oracle Fusion DOO to bring these entities together. Disturbing the Peace with Acquisitions Quite often a company's ERP system is disrupted when it acquires a new company. An acquisition can inject a new set of processes and systems -- or even introduce an entirely new business like Sun's hardware did at Oracle. This challenge has been a driver for some of our DOO customers. A large power management company is using Oracle Fusion DOO to provide the flexibility to rapidly integrate additional products and services into its central fulfillment operation. The Flip Side of Fulfillment Meanwhile, we haven't ignored similar challenges on the supply side of the equation. Specifically, how to manage complex supply in a flexible way when there are multiple trading parties involved? How to manage the supply to suppliers? How to manage critical components that need to merge in a tier two or tier three supply chain? By investing in supply orchestration solutions for the virtual enterprise, we plan to give users better visibility into their network of suppliers to help them drive down costs. We also think this technology and full orchestration process can be applied to the financial side of organizations. An example is transactions that flow through complex internal structures to minimize tax exposure. We can help companies manage those transactions effectively by thinking about the internal organization as a virtual enterprise and bringing the same solution set to this internal challenge. The Clear Front Runner No other company is investing in solving the virtual enterprise supply chain issues like Oracle is. Oracle is in a unique position to become the gold standard in this market space. We have the infrastructure of Oracle technology. We already have an Oracle Fusion DOO application which embraces the best of what's required in this area. And we're absolutely committed to extending our Fusion solution to other use cases and delivering even more business value.

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MapReduce in DryadLINQ and PLINQ

- by JoshReuben

MapReduce See http://en.wikipedia.org/wiki/Mapreduce The MapReduce pattern aims to handle large-scale computations across a cluster of servers, often involving massive amounts of data. "The computation takes a set of input key/value pairs, and produces a set of output key/value pairs. The developer expresses the computation as two Func delegates: Map and Reduce. Map - takes a single input pair and produces a set of intermediate key/value pairs. The MapReduce function groups results by key and passes them to the Reduce function. Reduce - accepts an intermediate key I and a set of values for that key. It merges together these values to form a possibly smaller set of values. Typically just zero or one output value is produced per Reduce invocation. The intermediate values are supplied to the user's Reduce function via an iterator." the canonical MapReduce example: counting word frequency in a text file. MapReduce using DryadLINQ see http://research.microsoft.com/en-us/projects/dryadlinq/ and http://connect.microsoft.com/Dryad DryadLINQ provides a simple and straightforward way to implement MapReduce operations. This The implementation has two primary components: A Pair structure, which serves as a data container. A MapReduce method, which counts word frequency and returns the top five words. The Pair Structure - Pair has two properties: Word is a string that holds a word or key. Count is an int that holds the word count. The structure also overrides ToString to simplify printing the results. The following example shows the Pair implementation. public struct Pair { private string word; private int count; public Pair(string w, int c) { word = w; count = c; } public int Count { get { return count; } } public string Word { get { return word; } } public override string ToString() { return word + ":" + count.ToString(); } } The MapReduce function that gets the results. the input data could be partitioned and distributed across the cluster. 1. Creates a DryadTable<LineRecord> object, inputTable, to represent the lines of input text. For partitioned data, use GetPartitionedTable<T> instead of GetTable<T> and pass the method a metadata file. 2. Applies the SelectMany operator to inputTable to transform the collection of lines into collection of words. The String.Split method converts the line into a collection of words. SelectMany concatenates the collections created by Split into a single IQueryable<string> collection named words, which represents all the words in the file. 3. Performs the Map part of the operation by applying GroupBy to the words object. The GroupBy operation groups elements with the same key, which is defined by the selector delegate. This creates a higher order collection, whose elements are groups. In this case, the delegate is an identity function, so the key is the word itself and the operation creates a groups collection that consists of groups of identical words. 4. Performs the Reduce part of the operation by applying Select to groups. This operation reduces the groups of words from Step 3 to an IQueryable<Pair> collection named counts that represents the unique words in the file and how many instances there are of each word. Each key value in groups represents a unique word, so Select creates one Pair object for each unique word. IGrouping.Count returns the number of items in the group, so each Pair object's Count member is set to the number of instances of the word. 5. Applies OrderByDescending to counts. This operation sorts the input collection in descending order of frequency and creates an ordered collection named ordered. 6. Applies Take to ordered to create an IQueryable<Pair> collection named top, which contains the 100 most common words in the input file, and their frequency. Test then uses the Pair object's ToString implementation to print the top one hundred words, and their frequency. public static IQueryable<Pair> MapReduce( string directory, string fileName, int k) { DryadDataContext ddc = new DryadDataContext("file://" + directory); DryadTable<LineRecord> inputTable = ddc.GetTable<LineRecord>(fileName); IQueryable<string> words = inputTable.SelectMany(x => x.line.Split(' ')); IQueryable<IGrouping<string, string>> groups = words.GroupBy(x => x); IQueryable<Pair> counts = groups.Select(x => new Pair(x.Key, x.Count())); IQueryable<Pair> ordered = counts.OrderByDescending(x => x.Count); IQueryable<Pair> top = ordered.Take(k); return top; } To Test: IQueryable<Pair> results = MapReduce(@"c:\DryadData\input", "TestFile.txt", 100); foreach (Pair words in results) Debug.Print(words.ToString()); Note: DryadLINQ applications can use a more compact way to represent the query: return inputTable .SelectMany(x => x.line.Split(' ')) .GroupBy(x => x) .Select(x => new Pair(x.Key, x.Count())) .OrderByDescending(x => x.Count) .Take(k); MapReduce using PLINQ The pattern is relevant even for a single multi-core machine, however. We can write our own PLINQ MapReduce in a few lines. the Map function takes a single input value and returns a set of mapped values àLINQ's SelectMany operator. These are then grouped according to an intermediate key à LINQ GroupBy operator. The Reduce function takes each intermediate key and a set of values for that key, and produces any number of outputs per key à LINQ SelectMany again. We can put all of this together to implement MapReduce in PLINQ that returns a ParallelQuery<T> public static ParallelQuery<TResult> MapReduce<TSource, TMapped, TKey, TResult>( this ParallelQuery<TSource> source, Func<TSource, IEnumerable<TMapped>> map, Func<TMapped, TKey> keySelector, Func<IGrouping<TKey, TMapped>, IEnumerable<TResult>> reduce) { return source .SelectMany(map) .GroupBy(keySelector) .SelectMany(reduce); } the map function takes in an input document and outputs all of the words in that document. The grouping phase groups all of the identical words together, such that the reduce phase can then count the words in each group and output a word/count pair for each grouping: var files = Directory.EnumerateFiles(dirPath, "*.txt").AsParallel(); var counts = files.MapReduce( path => File.ReadLines(path).SelectMany(line => line.Split(delimiters)), word => word, group => new[] { new KeyValuePair<string, int>(group.Key, group.Count()) });

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General Purpose ASP.NET Data Source Control

- by Ricardo Peres

OK, you already know about the ObjectDataSource control, so what’s wrong with it? Well, for once, it doesn’t pass any context to the SelectMethod, you only get the parameters supplied on the SelectParameters plus the desired ordering, starting page and maximum number of rows to display. Also, you must have two separate methods, one for actually retrieving the data, and the other for getting the total number of records (SelectCountMethod). Finally, you don’t get a chance to alter the supplied data before you bind it to the target control. I wanted something simple to use, and more similar to ASP.NET 4.5, where you can have the select method on the page itself, so I came up with CustomDataSource. Here’s how to use it (I chose a GridView, but it works equally well with any regular data-bound control): 1: <web:CustomDataSourceControl runat="server" ID="datasource" PageSize="10" OnData="OnData" /> 2: <asp:GridView runat="server" ID="grid" DataSourceID="datasource" DataKeyNames="Id" PageSize="10" AllowPaging="true" AllowSorting="true" /> The OnData event handler receives a DataEventArgs instance, which contains some properties that describe the desired paging location and size, and it’s where you return the data plus the total record count. Here’s a quick example: 1: protected void OnData(object sender, DataEventArgs e) 2: { 3: //just return some data 4: var data = Enumerable.Range(e.StartRowIndex, e.PageSize).Select(x => new { Id = x, Value = x.ToString(), IsPair = ((x % 2) == 0) }); 5: e.Data = data; 6: //the total number of records 7: e.TotalRowCount = 100; 8: } Here’s the code for the DataEventArgs: 1: [Serializable] 2: public class DataEventArgs : EventArgs 3: { 4: public DataEventArgs(Int32 pageSize, Int32 startRowIndex, String sortExpression, IOrderedDictionary parameters) 5: { 6: this.PageSize = pageSize; 7: this.StartRowIndex = startRowIndex; 8: this.SortExpression = sortExpression; 9: this.Parameters = parameters; 10: } 11: 12: public IEnumerable Data 13: { 14: get; 15: set; 16: } 17: 18: public IOrderedDictionary Parameters 19: { 20: get; 21: private set; 22: } 23: 24: public String SortExpression 25: { 26: get; 27: private set; 28: } 29: 30: public Int32 StartRowIndex 31: { 32: get; 33: private set; 34: } 35: 36: public Int32 PageSize 37: { 38: get; 39: private set; 40: } 41: 42: public Int32 TotalRowCount 43: { 44: get; 45: set; 46: } 47: } As you can guess, the StartRowIndex and PageSize receive the starting row and the desired page size, where the page size comes from the PageSize property on the markup. There’s also a SortExpression, which gets passed the sorted-by column and direction (if descending) and a dictionary containing all the values coming from the SelectParameters collection, if any. All of these are read only, and it is your responsibility to fill in the Data and TotalRowCount. The code for the CustomDataSource is very simple: 1: [NonVisualControl] 2: public class CustomDataSourceControl : DataSourceControl 3: { 4: public CustomDataSourceControl() 5: { 6: this.SelectParameters = new ParameterCollection(); 7: } 8: 9: protected override DataSourceView GetView(String viewName) 10: { 11: return (new CustomDataSourceView(this, viewName)); 12: } 13: 14: internal void GetData(DataEventArgs args) 15: { 16: this.OnData(args); 17: } 18: 19: protected virtual void OnData(DataEventArgs args) 20: { 21: EventHandler<DataEventArgs> data = this.Data; 22: 23: if (data != null) 24: { 25: data(this, args); 26: } 27: } 28: 29: [Browsable(false)] 30: [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)] 31: [PersistenceMode(PersistenceMode.InnerProperty)] 32: public ParameterCollection SelectParameters 33: { 34: get; 35: private set; 36: } 37: 38: public event EventHandler<DataEventArgs> Data; 39: 40: public Int32 PageSize 41: { 42: get; 43: set; 44: } 45: } Also, the code for the accompanying internal – as there is no need to use it from outside of its declaring assembly - data source view: 1: sealed class CustomDataSourceView : DataSourceView 2: { 3: private readonly CustomDataSourceControl dataSourceControl = null; 4: 5: public CustomDataSourceView(CustomDataSourceControl dataSourceControl, String viewName) : base(dataSourceControl, viewName) 6: { 7: this.dataSourceControl = dataSourceControl; 8: } 9: 10: public override Boolean CanPage 11: { 12: get 13: { 14: return (true); 15: } 16: } 17: 18: public override Boolean CanRetrieveTotalRowCount 19: { 20: get 21: { 22: return (true); 23: } 24: } 25: 26: public override Boolean CanSort 27: { 28: get 29: { 30: return (true); 31: } 32: } 33: 34: protected override IEnumerable ExecuteSelect(DataSourceSelectArguments arguments) 35: { 36: IOrderedDictionary parameters = this.dataSourceControl.SelectParameters.GetValues(HttpContext.Current, this.dataSourceControl); 37: DataEventArgs args = new DataEventArgs(this.dataSourceControl.PageSize, arguments.StartRowIndex, arguments.SortExpression, parameters); 38: 39: this.dataSourceControl.GetData(args); 40: 41: arguments.TotalRowCount = args.TotalRowCount; 42: arguments.MaximumRows = this.dataSourceControl.PageSize; 43: arguments.AddSupportedCapabilities(DataSourceCapabilities.Page | DataSourceCapabilities.Sort | DataSourceCapabilities.RetrieveTotalRowCount); 44: arguments.RetrieveTotalRowCount = true; 45: 46: if (!(args.Data is ICollection)) 47: { 48: return (args.Data.OfType<Object>().ToList()); 49: } 50: else 51: { 52: return (args.Data); 53: } 54: } 55: } As always, looking forward to hearing from you!

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Responsive Design for your ADF Faces Web Applications

- by Shay Shmeltzer

Responsive web applications are a common pattern for designing web pages that adjust their UI based on the device that access them. With the increase in the number of ADF applications that are being accessed from mobile phones and tablet we are getting more and more questions around this topic. Steven Davelaar wrote a comprehensive article covering key concepts in this area that you can find here. The article focuses on what I would refer to as server adaptive application, where the server adapts the UI it generates based on the device that is accessing the server. However there is one more technique that is not covered in that article and can be used with Oracle ADF - it is CSS manipulation on the client that can achieve responsive design. I'll cover this technique in this blog entry. The main advantage of this technique is that the UI manipulation does not require the server to send over a new UI when a change is needed. This for example allows your page to change immediately when you change the orientation of your device. (By the way this example was developed for one of the seminars in the upcoming Oracle ADF OTN Virtual Developer Day). In the demo that you'll see below you'll see a single page that changes the way it is displayed based on the orientation of the device. Here is the page with the tablet in landscape and portrait: To achieve this I'm using a CSS media query in my page template that changes the display property of a couple of style classes that are used in my page. The media query has this format: @media screen and (max-width:700px) { .narrow { display: inline; } .wide { display: none; } .adjustFont { font-size: small; } .icon-home { font-size: 24px; } } This changes the properties of the same styleClasses that are defined in my application's skin. Here is a quick demo video that shows you the full application and explains how it works. For those looking to replicate this, here are the basic files: skin1.css @charset "UTF-8";/**ADFFaces_Skin_File / DO NOT REMOVE**/@namespace af "http://xmlns.oracle.com/adf/faces/rich";@namespace dvt "http://xmlns.oracle.com/dss/adf/faces";.wide { display: inline;}.narrow { display: none;}.adjustFont { font-size: large;}.icon-home { font-family: 'UIShellUGH'; -webkit-font-smoothing: antialiased; font-size: 36px; color: #ffa000;} pageTemplate: <?xml version='1.0' encoding='UTF-8'?><af:pageTemplateDef xmlns:af="http://xmlns.oracle.com/adf/faces/rich" var="attrs" definition="private" xmlns:afc="http://xmlns.oracle.com/adf/faces/rich/component"> <af:xmlContent> <afc:component> <afc:description>A template that will work on phones and desktop</afc:description> <afc:display-name>ResponsiveTemplate</afc:display-name> <afc:facet> <afc:facet-name>main</afc:facet-name> </afc:facet> </afc:component> </af:xmlContent> <meta name="viewport" content="width=device-width, initial-scale=1"/> <af:resource type="css">@media screen and (max-width:700px) { .narrow { display: inline; } .wide { display: none; } .adjustFont { font-size: small; } .icon-home { font-size: 24px; } }@font-face { font-family: 'UIShellUGH'; src: url(data:application/x-font-woff;charset=utf-8;base64,d09GRk9UVE8AA..removed code here...AzV6b1g==)format('truetype'); font-weight: normal; font-style: normal; } </af:resource> <af:panelGroupLayout id="pt_pgl4" layout="vertical" styleClass="sizeStyle"> <af:panelGridLayout id="pt_pgl1"> <af:gridRow marginTop="5px" height="40px" id="pt_gr1"> <af:gridCell marginStart="5px" width="100%" marginEnd="5px" id="pt_gc1"> <af:panelGroupLayout id="pt_pgl3" halign="center" layout="horizontal"> <af:outputText value="h" id="ot2" styleClass="icon-home"/> <af:outputText value="HR System" id="ot3" styleClass="adjustFont"/> </af:panelGroupLayout> </af:gridCell> </af:gridRow> <af:gridRow marginTop="5px" height="auto" id="pt_gr2"> <af:gridCell marginStart="5px" width="100%" marginEnd="5px" id="pt_gc2" halign="stretch"> <af:panelGroupLayout id="pt_pgl2" layout="scroll"> <af:facetRef facetName="main"/> </af:panelGroupLayout> </af:gridCell> </af:gridRow> <af:gridRow marginTop="5px" height="20px" marginBottom="5px" id="pt_gr3"> <af:gridCell marginStart="5px" width="100%" marginEnd="5px" id="pt_gc3"> <af:panelGroupLayout id="pt_pgl5" layout="vertical" halign="center"> <af:separator id="pt_s1"/> <af:outputText value="Copyright Oracle Corp. 2013" id="pt_ot1" styleClass="adjustFont"/> </af:panelGroupLayout> </af:gridCell> </af:gridRow> </af:panelGridLayout> </af:panelGroupLayout></af:pageTemplateDef> Example from the page: <af:gridRow id="gr3"> <af:gridCell id="gc7" columnSpan="2"> <af:panelGroupLayout id="pgl8" styleClass="narrow"> <af:link text="Menu" id="l1"> <af:showPopupBehavior triggerType="action" popupId="p1" align="afterEnd"/> </af:link> </af:panelGroupLayout> <af:panelGroupLayout id="pgl7" styleClass="wide"> <af:navigationPane id="np1" hint="buttons"> <af:commandNavigationItem text="Departments" id="cni1"/> <af:commandNavigationItem text="Employees" id="cni2"/> <af:commandNavigationItem text="Salaries" id="cni3"/> <af:commandNavigationItem text="Jobs" id="cni4"/> <af:commandNavigationItem text="Services" id="cni5"/> <af:commandNavigationItem text="Support" id="cni6"/> <af:commandNavigationItem text="Help" id="cni7"/> </af:navigationPane> </af:panelGroupLayout> </af:gridCell> </af:gridRow>

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Why do we (really) program to interfaces?

- by Kyle Burns

One of the earliest lessons I was taught in Enterprise development was "always program against an interface". This was back in the VB6 days and I quickly learned that no code would be allowed to move to the QA server unless my business objects and data access objects each are defined as an interface and have a matching implementation class. Why? "It's more reusable" was one answer. "It doesn't tie you to a specific implementation" a slightly more knowing answer. And let's not forget the discussion ending "it's a standard". The problem with these responses was that senior people didn't really understand the reason we were doing the things we were doing and because of that, we were entirely unable to realize the intent behind the practice - we simply used interfaces and had a bunch of extra code to maintain to show for it. It wasn't until a few years later that I finally heard the term "Inversion of Control". Simply put, "Inversion of Control" takes the creation of objects that used to be within the control (and therefore a responsibility of) of your component and moves it to some outside force. For example, consider the following code which follows the old "always program against an interface" rule in the manner of many corporate development shops: 1: ICatalog catalog = new Catalog(); 2: Category[] categories = catalog.GetCategories(); In this example, I met the requirement of the rule by declaring the variable as ICatalog, but I didn't hit "it doesn't tie you to a specific implementation" because I explicitly created an instance of the concrete Catalog object. If I want to test the functionality of the code I just wrote I have to have an environment in which Catalog can be created along with any of the resources upon which it depends (e.g. configuration files, database connections, etc) in order to test my functionality. That's a lot of setup work and one of the things that I think ultimately discourages real buy-in of unit testing in many development shops. So how do I test my code without needing Catalog to work? A very primitive approach I've seen is to change the line the instantiates catalog to read: 1: ICatalog catalog = new FakeCatalog(); once the test is run and passes, the code is switched back to the real thing. This obviously poses a huge risk for introducing test code into production and in my opinion is worse than just keeping the dependency and its associated setup work. Another popular approach is to make use of Factory methods which use an object whose "job" is to know how to obtain a valid instance of the object. Using this approach, the code may look something like this: 1: ICatalog catalog = CatalogFactory.GetCatalog(); The code inside the factory is responsible for deciding "what kind" of catalog is needed. This is a far better approach than the previous one, but it does make projects grow considerably because now in addition to the interface, the real implementation, and the fake implementation(s) for testing you have added a minimum of one factory (or at least a factory method) for each of your interfaces. Once again, developers say "that's too complicated and has me writing a bunch of useless code" and quietly slip back into just creating a new Catalog and chalking any test failures up to "it will probably work on the server". This is where software intended specifically to facilitate Inversion of Control comes into play. There are many libraries that take on the Inversion of Control responsibilities in .Net and most of them have many pros and cons. From this point forward I'll discuss concepts from the standpoint of the Unity framework produced by Microsoft's Patterns and Practices team. I'm primarily focusing on this library because it questions about it inspired this posting. At Unity's core and that of most any IoC framework is a catalog or registry of components. This registry can be configured either through code or using the application's configuration file and in the most simple terms says "interface X maps to concrete implementation Y". It can get much more complicated, but I want to keep things at the "what does it do" level instead of "how does it do it". The object that exposes most of the Unity functionality is the UnityContainer. This object exposes methods to configure the catalog as well as the Resolve<T> method which is used to obtain an instance of the type represented by T. When using the Resolve<T> method, Unity does not necessarily have to just "new up" the requested object, but also can track dependencies of that object and ensure that the entire dependency chain is satisfied. There are three basic ways that I have seen Unity used within projects. Those are through classes directly using the Unity container, classes requiring injection of dependencies, and classes making use of the Service Locator pattern. The first usage of Unity is when classes are aware of the Unity container and directly call its Resolve method whenever they need the services advertised by an interface. The up side of this approach is that IoC is utilized, but the down side is that every class has to be aware that Unity is being used and tied directly to that implementation. Many developers don't like the idea of as close a tie to specific IoC implementation as is represented by using Unity within all of your classes and for the most part I agree that this isn't a good idea. As an alternative, classes can be designed for Dependency Injection. Dependency Injection is where a force outside the class itself manipulates the object to provide implementations of the interfaces that the class needs to interact with the outside world. This is typically done either through constructor injection where the object has a constructor that accepts an instance of each interface it requires or through property setters accepting the service providers. When using dependency, I lean toward the use of constructor injection because I view the constructor as being a much better way to "discover" what is required for the instance to be ready for use. During resolution, Unity looks for an injection constructor and will attempt to resolve instances of each interface required by the constructor, throwing an exception of unable to meet the advertised needs of the class. The up side of this approach is that the needs of the class are very clearly advertised and the class is unaware of which IoC container (if any) is being used. The down side of this approach is that you're required to maintain the objects passed to the constructor as instance variables throughout the life of your object and that objects which coordinate with many external services require a lot of additional constructor arguments (this gets ugly and may indicate a need for refactoring). The final way that I've seen and used Unity is to make use of the ServiceLocator pattern, of which the Patterns and Practices team has also provided a Unity-compatible implementation. When using the ServiceLocator, your class calls ServiceLocator.Retrieve in places where it would have called Resolve on the Unity container. Like using Unity directly, it does tie you directly to the ServiceLocator implementation and makes your code aware that dependency injection is taking place, but it does have the up side of giving you the freedom to swap out the underlying IoC container if necessary. I'm not hugely concerned with hiding IoC entirely from the class (I view this as a "nice to have"), so the single biggest problem that I see with the ServiceLocator approach is that it provides no way to proactively advertise needs in the way that constructor injection does, allowing more opportunity for difficult to track runtime errors. This blog entry has not been intended in any way to be a definitive work on IoC, but rather as something to spur thought about why we program to interfaces and some ways to reach the intended value of the practice instead of having it just complicate your code. I hope that it helps somebody begin or continue a journey away from being a "Cargo Cult Programmer".

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We've completed the first iteration

- by CliveT

There are a lot of features in C# that are implemented by the compiler and not by the underlying platform. One such feature is a lambda expression. Since local variables cannot be accessed once the current method activation finishes, the compiler has to go out of its way to generate a new class which acts as a home for any variable whose lifetime needs to be extended past the activation of the procedure. Take the following example: Random generator = new Random(); Func func = () = generator.Next(10); In this case, the compiler generates a new class called c_DisplayClass1 which is marked with the CompilerGenerated attribute. [CompilerGenerated] private sealed class c__DisplayClass1 { // Fields public Random generator; // Methods public int b__0() { return this.generator.Next(10); } } Two quick comments on this: (i) A display was the means that compilers for languages like Algol recorded the various lexical contours of the nested procedure activations on the stack. I imagine that this is what has led to the name. (ii) It is a shame that the same attribute is used to mark all compiler generated classes as it makes it hard to figure out what they are being used for. Indeed, you could imagine optimisations that the runtime could perform if it knew that classes corresponded to certain high level concepts. We can see that the local variable generator has been turned into a field in the class, and the body of the lambda expression has been turned into a method of the new class. The code that builds the Func object simply constructs an instance of this class and initialises the fields to their initial values. c__DisplayClass1 class2 = new c__DisplayClass1(); class2.generator = new Random(); Func func = new Func(class2.b__0); Reflector already contains code to spot this pattern of code and reproduce the form containing the lambda expression, so this is example is correctly decompiled. The use of compiler generated code is even more spectacular in the case of iterators. C# introduced the idea of a method that could automatically store its state between calls, so that it can pick up where it left off. The code can express the logical flow with yield return and yield break denoting places where the method should return a particular value and be prepared to resume. { yield return 1; yield return 2; yield return 3; } Of course, there was already a .NET pattern for expressing the idea of returning a sequence of values with the computation proceeding lazily (in the sense that the work for the next value is executed on demand). This is expressed by the IEnumerable interface with its Current property for fetching the current value and the MoveNext method for forcing the computation of the next value. The sequence is terminated when this method returns false. The C# compiler links these two ideas together so that an IEnumerator returning method using the yield keyword causes the compiler to produce the implementation of an Iterator. Take the following piece of code. IEnumerable GetItems() { yield return 1; yield return 2; yield return 3; } The compiler implements this by defining a new class that implements a state machine. This has an integer state that records which yield point we should go to if we are resumed. It also has a field that records the Current value of the enumerator and a field for recording the thread. This latter value is used for optimising the creation of iterator instances. [CompilerGenerated] private sealed class d__0 : IEnumerable, IEnumerable, IEnumerator, IEnumerator, IDisposable { // Fields private int 1__state; private int 2__current; public Program 4__this; private int l__initialThreadId; The body gets converted into the code to construct and initialize this new class. private IEnumerable GetItems() { d__0 d__ = new d__0(-2); d__.4__this = this; return d__; } When the class is constructed we set the state, which was passed through as -2 and the current thread. public d__0(int 1__state) { this.1__state = 1__state; this.l__initialThreadId = Thread.CurrentThread.ManagedThreadId; } The state needs to be set to 0 to represent a valid enumerator and this is done in the GetEnumerator method which optimises for the usual case where the returned enumerator is only used once. IEnumerator IEnumerable.GetEnumerator() { if ((Thread.CurrentThread.ManagedThreadId == this.l__initialThreadId) && (this.1__state == -2)) { this.1__state = 0; return this; } The state machine itself is implemented inside the MoveNext method. private bool MoveNext() { switch (this.1__state) { case 0: this.1__state = -1; this.2__current = 1; this.1__state = 1; return true; case 1: this.1__state = -1; this.2__current = 2; this.1__state = 2; return true; case 2: this.1__state = -1; this.2__current = 3; this.1__state = 3; return true; case 3: this.1__state = -1; break; } return false; } At each stage, the current value of the state is used to determine how far we got, and then we generate the next value which we return after recording the next state. Finally we return false from the MoveNext to signify the end of the sequence. Of course, that example was really simple. The original method body didn't have any local variables. Any local variables need to live between the calls to MoveNext and so they need to be transformed into fields in much the same way that we did in the case of the lambda expression. More complicated MoveNext methods are required to deal with resources that need to be disposed when the iterator finishes, and sometimes the compiler uses a temporary variable to hold the return value. Why all of this explanation? We've implemented the de-compilation of iterators in the current EAP version of Reflector (7). This contrasts with previous version where all you could do was look at the MoveNext method and try to figure out the control flow. There's a fair amount of things we have to do. We have to spot the use of a CompilerGenerated class which implements the Enumerator pattern. We need to go to the class and figure out the fields corresponding to the local variables. We then need to go to the MoveNext method and try to break it into the various possible states and spot the state transitions. We can then take these pieces and put them back together into an object model that uses yield return to show the transition points. After that Reflector can carry on optimising using its usual optimisations. The pattern matching is currently a little too sensitive to changes in the code generation, and we only do a limited analysis of the MoveNext method to determine use of the compiler generated fields. In some ways, it is a pity that iterators are compiled away and there is no metadata that reflects the original intent. Without it, we are always going to dependent on our knowledge of the compiler's implementation. For example, we have noticed that the Async CTP changes the way that iterators are code generated, so we'll have to do some more work to support that. However, with that warning in place, we seem to do a reasonable job of decompiling the iterators that are built into the framework. Hopefully, the EAP will give us a chance to find examples where we don't spot the pattern correctly or regenerate the wrong code, and we can improve things. Please give it a go, and report any problems.

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PostSharp, Obfuscation, and IL

- by simonc

Aspect-oriented programming (AOP) is a relatively new programming paradigm. Originating at Xerox PARC in 1994, the paradigm was first made available for general-purpose development as an extension to Java in 2001. From there, it has quickly been adapted for use in all the common languages used today. In the .NET world, one of the primary AOP toolkits is PostSharp. Attributes and AOP Normally, attributes in .NET are entirely a metadata construct. Apart from a few special attributes in the .NET framework, they have no effect whatsoever on how a class or method executes within the CLR. Only by using reflection at runtime can you access any attributes declared on a type or type member. PostSharp changes this. By declaring a custom attribute that derives from PostSharp.Aspects.Aspect, applying it to types and type members, and running the resulting assembly through the PostSharp postprocessor, you can essentially declare 'clever' attributes that change the behaviour of whatever the aspect has been applied to at runtime. A simple example of this is logging. By declaring a TraceAttribute that derives from OnMethodBoundaryAspect, you can automatically log when a method has been executed: public class TraceAttribute : PostSharp.Aspects.OnMethodBoundaryAspect { public override void OnEntry(MethodExecutionArgs args) { MethodBase method = args.Method; System.Diagnostics.Trace.WriteLine( String.Format( "Entering {0}.{1}.", method.DeclaringType.FullName, method.Name)); } public override void OnExit(MethodExecutionArgs args) { MethodBase method = args.Method; System.Diagnostics.Trace.WriteLine( String.Format( "Leaving {0}.{1}.", method.DeclaringType.FullName, method.Name)); } } [Trace] public void MethodToLog() { ... } Now, whenever MethodToLog is executed, the aspect will automatically log entry and exit, without having to add the logging code to MethodToLog itself. PostSharp Performance Now this does introduce a performance overhead - as you can see, the aspect allows access to the MethodBase of the method the aspect has been applied to. If you were limited to C#, you would be forced to retrieve each MethodBase instance using Type.GetMethod(), matching on the method name and signature. This is slow. Fortunately, PostSharp is not limited to C#. It can use any instruction available in IL. And in IL, you can do some very neat things. Ldtoken C# allows you to get the Type object corresponding to a specific type name using the typeof operator: Type t = typeof(Random); The C# compiler compiles this operator to the following IL: ldtoken [mscorlib]System.Random call class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle( valuetype [mscorlib]System.RuntimeTypeHandle) The ldtoken instruction obtains a special handle to a type called a RuntimeTypeHandle, and from that, the Type object can be obtained using GetTypeFromHandle. These are both relatively fast operations - no string lookup is required, only direct assembly and CLR constructs are used. However, a little-known feature is that ldtoken is not just limited to types; it can also get information on methods and fields, encapsulated in a RuntimeMethodHandle or RuntimeFieldHandle: // get a MethodBase for String.EndsWith(string) ldtoken method instance bool [mscorlib]System.String::EndsWith(string) call class [mscorlib]System.Reflection.MethodBase [mscorlib]System.Reflection.MethodBase::GetMethodFromHandle( valuetype [mscorlib]System.RuntimeMethodHandle) // get a FieldInfo for the String.Empty field ldtoken field string [mscorlib]System.String::Empty call class [mscorlib]System.Reflection.FieldInfo [mscorlib]System.Reflection.FieldInfo::GetFieldFromHandle( valuetype [mscorlib]System.RuntimeFieldHandle) These usages of ldtoken aren't usable from C# or VB, and aren't likely to be added anytime soon (Eric Lippert's done a blog post on the possibility of adding infoof, methodof or fieldof operators to C#). However, PostSharp deals directly with IL, and so can use ldtoken to get MethodBase objects quickly and cheaply, without having to resort to string lookups. The kicker However, there are problems. Because ldtoken for methods or fields isn't accessible from C# or VB, it hasn't been as well-tested as ldtoken for types. This has resulted in various obscure bugs in most versions of the CLR when dealing with ldtoken and methods, and specifically, generic methods and methods of generic types. This means that PostSharp was behaving incorrectly, or just plain crashing, when aspects were applied to methods that were generic in some way. So, PostSharp has to work around this. Without using the metadata tokens directly, the only way to get the MethodBase of generic methods is to use reflection: Type.GetMethod(), passing in the method name as a string along with information on the signature. Now, this works fine. It's slower than using ldtoken directly, but it works, and this only has to be done for generic methods. Unfortunately, this poses problems when the assembly is obfuscated. PostSharp and Obfuscation When using ldtoken, obfuscators don't affect how PostSharp operates. Because the ldtoken instruction directly references the type, method or field within the assembly, it is unaffected if the name of the object is changed by an obfuscator. However, the indirect loading used for generic methods was breaking, because that uses the name of the method when the assembly is put through the PostSharp postprocessor to lookup the MethodBase at runtime. If the name then changes, PostSharp can't find it anymore, and the assembly breaks. So, PostSharp needs to know about any changes an obfuscator does to an assembly. The way PostSharp does this is by adding another layer of indirection. When PostSharp obfuscation support is enabled, it includes an extra 'name table' resource in the assembly, consisting of a series of method & type names. When PostSharp needs to lookup a method using reflection, instead of encoding the method name directly, it looks up the method name at a fixed offset inside that name table: MethodBase genericMethod = typeof(ContainingClass).GetMethod(GetNameAtIndex(22)); PostSharp.NameTable resource: ... 20: get_Prop1 21: set_Prop1 22: DoFoo 23: GetWibble When the assembly is later processed by an obfuscator, the obfuscator can replace all the method and type names within the name table with their new name. That way, the reflection lookups performed by PostSharp will now use the new names, and everything will work as expected: MethodBase genericMethod = typeof(#kGy).GetMethod(GetNameAtIndex(22)); PostSharp.NameTable resource: ... 20: #kkA 21: #zAb 22: #EF5a 23: #2tg As you can see, this requires direct support by an obfuscator in order to perform these rewrites. Dotfuscator supports it, and now, starting with SmartAssembly 6.6.4, SmartAssembly does too. So, a relatively simple solution to a tricky problem, with some CLR bugs thrown in for good measure. You don't see those every day! Cross posted from Simple Talk.

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I Know What I Did This Summer: Put Down Trex Decking

- by thatjeffsmith

If you’re wondering why I would bore everyone with my pictures and frequent status updates/tweets from the past week – it’s so I could document the process of refurbishing my deck, or what some would call a porch. When we go to take a vacation, buy a car, do anything – we also read personal blogs to get the real story. So, if you’re curious about what it takes to tackle this sort of project, read on. Skills/Equipment/Manpower We Possessed I took the old decking out by myself. I’m about 230 lbs, more than 6′ tall, and I’m pretty healthy. This took about 8 hours over two afternoons. Three of us put the deck back together. My wife has two engineering degrees. Her father also has two engineering degrees. Lots of brainpower available here. Also, her dad ran the public works department for a country for more than 20 years – so lots and lots of practical experience on hand. We had a compound mitre saw, a skilsaw, 2-3 crowbars, a framing hammer, 3 cordless drills, a corded drill, lots of sawhorses, a power sander, an angle grinder, a 10×10 Coleman canopy tent, a Ford F-150 pickup truck, outdoor speakers and lots of iTunes playlists, plenty of water and cold beer. Why We Did This Our deck was relatively young – it was built in 2005. However, the pressure treated boards must not have been adequately maintained before we bought the house. I had powerwashed the deck every other year and had it stained a few times. The boards just rotted. We’re going to be in the house for a long time, and we wanted something that would look nice and require little maintenance. More bad deck boards The deck boards were in bad shape Things We Learned The two most important things: The hidden fasteners have to be put in JUST right. Wedge them into the grooved board, then bend down the bit that is screwed down. We didn’t do this on the first board and couldn’t get the second board to fit nearly close enough. Watching the official TREX YouTube video helped immensely, and we should have watched that first. When pre-drilling holes for the boards that need screwed down – DO NOT pre-drill through the underlying framing wood. ONLY pre-drill through the TREX itself. The screw won’t seat in the board properly. Instead of sitting down flush with the board, it will stop at the top of the board and just spin. I had to call the the place that sold me the screws to find this out. So about a third of our screws look like crap. If it doesn’t look or feel right – stop everything and pick up your computer or your phone. It’s not right, and it will be much easier to stop and find out why. We didn’t do this, and now I’m going to see every screw that’s not flush with the boards and get upset. Oh well. The Process How much time did it take? Well I spent about 8 hours taking the deck apart. And then the 3 of use spent 8 hours the first day, 10 hours the second day, 8 hours the third, and another 6 hours on the fourth day. That’s like 104 man-hours. We supposedly saved four or five thousand dollars in labor, but don’t do the math here or you might get a bit upset. The main thing is that we got what we wanted, and there won’t be any surprises later. Now for some pictures… This 6”+ pry bar made the destruction of the old deck much easier Most of the joists, once exposed, were OK. This joist wasn’t sitting on ANYTHING before. We think a lazy gas person cut the board to sneak a gas line in. Awesome… These monster lag bolts had to be accounted for when putting in the additional framing The border pattern Sheri wanted to put in required a lot more framing. These were the first boards to go down – we screwed them in as there was no way to attach clips I sat, kicked in the boards, and then drilled these clips in – but my wife was able to go MUCH faster by using her hands to lock the boards in and drill on her knees. I liked locking the board in with my feet when they needed to be ‘encouraged’ to go straight. The first board took FOREVER to go in, but then when we got rolling, we were able to put in a 20′ board in less than 10 minutes. This was end of construction day #2 – we got much further than we thought we would. Ah, the dreaded last 10% – what to do here? Remember those ‘floating’ stringers? Yeah, we fixed that up a bit, too. My wife used a website (and her brain) to calculate exactly how to cut the stringers to give us the rise/run we needed with the proper clearance and all that jazz. The stairs with stringers and toe kicks – this was worth the effort It started raining on us as I screwed down the steps – this we managed to get our shade tent up on the deck to protect us from the rain too The stairs, finished Finished, mostly Good corner shot The top of the stairs Stairs, looking down Celebratory beer In Summary There are a few things we’re not happy with. I think we can fix them up – but later. I have a few things left to finish, rewire the lighting, get the gas grille put back in, and rehang some screen doors. I was expecting this to be a lot worse than it was. If I didn’t have the help, I would have never done it myself. But I’m glad that I did have that help and did do that project. It’s not often you get to spend that kind of qualify time with family and building cool stuff.

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Need personal advice on how to get out of a company..

- by SOfan

Hi, I am an SO user since past 6 months and this is the first time I am turning to SO for personal help. I have asked technical questions before with my real ID. I am stuck inside a service based IT company for the past one year and haven't been able to decide if to leave it, when to leave it and how to leave it. I had taken 2 weeks LWP on medical reason roughly at end of 1 year and then soon after reporting, I applied for 2 months more LWP (on medical/personal ground) with the intention of working on my health,take up a hobby class to ward off depression,pessimism, to have some fun in life, and to look for a job which I really would be excited about - that interests me and which matches with my strength. My leave starts from this Monday. So in any case, I had hard set in mind that I will leave the company after I join them back hopefully with some job offer already in hand (after figuring out what I want do). Neither I can stand the past project,past colleagues,company, HR, pathetically low salary. But if I really listen to my heart, I don't want to have to go back to that office after my sabbatical and again have to see those people. I will have to resign it after my sabbatical ends. Then HR people perhaps wont like it, may even accuse me on face or behind back that primary purpose of my leave must have been to hunt for a better job and I lied about medical and person reasons. Also, if they get nasty and force me to serve 2 months notice period. There is no way I see myself after sabbatical resuming in old project or starting new work. It will be a pain. Since they have already approved 2 months leave and stuff, ideally if they want, they should be just able to relieve me right on the next day after I join back. But, I don't know if they want to get nasty, will they mention about my 2 months sabbatical leave in my experience letter or more scary, the term medical/personal reason. I have hard earned my experience here, have worked against my will, mostly it has been painful and slogged like anything, because I realize the importance of work experience in IT industry. I don't have greed to have those 2 months included extra in my experience letter, but I don't want to mess up with my experience letter in a way which makes my next employer ask question, get suspicious, or be wary if I have any medical reason going on. Being an emotional,moody person or somebody who can't be in an environment, once my mind and heart starts hating it. I think it perhaps is best, if I resign on Monday itself telling them (in polite manner) something that look I took sabbatical for some reason but I don't want to resume working in the company after my sabbatical ends. So please accept my resignation. Now tell me what you want to do about my leave request, my notice period and when you are willing to relieve me. What should I write and how? Some background: I am working in an IT company in India.I am overqualified in the company. It is grossly underpaying me. My education qualifications far exceed anyone's in the whole company being a CS undergrad as well as a CS grad. I joined this company after finishing the grad. I had self-doubts about my skills and interest as a programmer. I like doing research oriented work, though didn't have any particular success during grad. My life here has been very hectic. The project containing many many sub-projects has kept me on my toes and I have never really liked the work. I have been playing against my strength. Also the company strict internet usage policy (you can't read gmails, can't browse any non-work related sites not even news). When working for a client, from the machine we can't even check company related emails.For this one has to go to kiosk like 5 machines in a small room etc. Most of the times those machines are not available, so it was not unusual to keep making rounds to these kiosk machines to check company emails, browse company related emails etc.So it was not so easy to keep in touch with company related basic affairs for a not particular careful person. Things like this which are new to me, make me feel restricted. I am an undecisive person with a sense of failure, self-doubt, not meeting up unrealistic expectation. Somewhere at back of mind, I envy my classmates who make a smooth transition from company to company without causing any gap in their resume. I on other hand have gaps in resume. I get tired after working in a place for sometime. problem with colleagues in general. I am not particular great with people, have few friends, not known for a fun nature, rather serious, scholar. I am not a typical conventional female. I think females are usually more disciplined. But I am not so. I reach office late (though after informing manager). I don't want to blame them entirely, because from my past, it is not unusual for me to get undecisive on things. Also I had doubts about my ability as researched and to succeed there. of building a relationship in a group, to have something to talk about, newspaper. I get cut-off from people. peer pressure. I make blunders in coding, lose patience. Consciously or unconsciously I feel contempt for people here, work here, environment here. I have doubts that either I go to a place which does innovation, does research oriented work, product biggies, have great motivated people, have competent people passionate about products they are building. But then I also doubt my ability to survive there. I have identified that an idea job for me would be 4 days a week, a high salary job. When among people in company/team, I can't think much. I need some time at home to read good authentic books written in good style on what work I am doing.So that I am comfortable with my understanding of work. I get into pressure easily under deadline and need 5th day to cool myself off. I took for 2 weeks leave, because each day was hell for me. May be the depression phase of bipolar is on and also partially it could be that being a work centered person, who derives happiness,self-esteem from work, haven't been enjoying work and have been working for the sole person of proving stability, and ability to stick, against all odds, and facing what challenges I see, bonding with people, identifying opportunities to learn in given task etc.have been averaging one day LWP in 1 week or 10 days. or may be because of my nature,ADD,not being able to switch context,out of touch with news, don't have a circle of friends with who I enjoy. less knowledge in general to talk about, just some technical stuff.anyway, so due to emotional reason, some practical reason etc, I wanted to be very sure before leaving. So my leave starts from Monday and I should feel happy about it. I have taken the leave to for a few purposes - to take care of my health by regular yoga/exercise (with project on, I just can't do anything regular), reassess myself to see what I want to try next which work I might like, look for next job, take up a hobby which I like say singing. I am not clear on my career,job aspiration. I have tried my hands on research. During this year appraisal yesterday, I even had some conflict with my last manager. In meeting with me one on one, he would say all nice things about me, but in feedback to new manager, he hasn't given any excellent feedback. It is all only good. I am angry at this old Manager. Also new manager also scolded me as I didn't agree to his appraisal and waited to hear myself from old Manager. He kind of scolded me for wasting his time. Am I being unethical somewhere? I am always very conscious of if I am cheating anywhere. What advice I am seeking? How to resign and what to write in resignation letter

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WIF, ADFS 2 and WCF–Part 2: The Service

- by Your DisplayName here!

OK – so let’s first start with a simple WCF service and connect that to ADFS 2 for authentication. The service itself simply echoes back the user’s claims – just so we can make sure it actually works and to see how the ADFS 2 issuance rules emit claims for the service: [ServiceContract(Namespace = "urn:leastprivilege:samples")] public interface IService { [OperationContract] List<ViewClaim> GetClaims(); } public class Service : IService { public List<ViewClaim> GetClaims() { var id = Thread.CurrentPrincipal.Identity as IClaimsIdentity; return (from c in id.Claims select new ViewClaim { ClaimType = c.ClaimType, Value = c.Value, Issuer = c.Issuer, OriginalIssuer = c.OriginalIssuer }).ToList(); } } The ViewClaim data contract is simply a DTO that holds the claim information. Next is the WCF configuration – let’s have a look step by step. First I mapped all my http based services to the federation binding. This is achieved by using .NET 4.0’s protocol mapping feature (this can be also done the 3.x way – but in that scenario all services will be federated): <protocolMapping> <add scheme="http" binding="ws2007FederationHttpBinding" /> </protocolMapping> Next, I provide a standard configuration for the federation binding: <bindings> <ws2007FederationHttpBinding> <binding> <security mode="TransportWithMessageCredential"> <message establishSecurityContext="false"> <issuerMetadata address="https://server/adfs/services/trust/mex" /> </message> </security> </binding> </ws2007FederationHttpBinding> </bindings> This binding points to our ADFS 2 installation metadata endpoint. This is all that is needed for svcutil (aka “Add Service Reference”) to generate the required client configuration. I also chose mixed mode security (SSL + basic message credential) for best performance. This binding also disables session – you can control that via the establishSecurityContext setting on the binding. This has its pros and cons. Something for a separate blog post, I guess. Next, the behavior section adds support for metadata and WIF: <behaviors> <serviceBehaviors> <behavior> <serviceMetadata httpsGetEnabled="true" /> <federatedServiceHostConfiguration /> </behavior> </serviceBehaviors> </behaviors> The next step is to add the WIF specific configuration (in <microsoft.identityModel />). First we need to specify the key material that we will use to decrypt the incoming tokens. This is optional for web applications but for web services you need to protect the proof key – so this is mandatory (at least for symmetric proof keys, which is the default): <serviceCertificate> <certificateReference storeLocation="LocalMachine" storeName="My" x509FindType="FindBySubjectDistinguishedName" findValue="CN=Service" /> </serviceCertificate> You also have to specify which incoming tokens you trust. This is accomplished by registering the thumbprint of the signing keys you want to accept. You get this information from the signing certificate configured in ADFS 2: <issuerNameRegistry type="...ConfigurationBasedIssuerNameRegistry"> <trustedIssuers> <add thumbprint="d1 … db" name="ADFS" /> </trustedIssuers> </issuerNameRegistry> The last step (promised) is to add the allowed audience URIs to the configuration – WCF clients use (by default – and we’ll come back to this) the endpoint address of the service: <audienceUris> <add value="https://machine/soapadfs/service.svc" /> </audienceUris> OK – that’s it – now we have a basic WCF service that uses ADFS 2 for authentication. The next step will be to set-up ADFS to issue tokens for this service. Afterwards we can explore various options on how to use this service from a client. Stay tuned… (if you want to have a look at the full source code or peek at the upcoming parts – you can download the complete solution here)

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D2K to OA Framework Transition

- by PRajkumar

What is the difference between D2K form and OA Framework? It is a very innocent but important question for someone that desires to make transition from D2K to OA Framework. I hope you have already read and implemented OA Framework Getting Started. I will re-visit my own experience of implementing HelloWorld program in "OA Framework". When I implemented HelloWorld a year ago, I had no clue as to what I was doing & why I was doing those steps. I merely copied the steps from Oracle Tutorial without understanding them. Hence in this blog, I will try to explain in simple manner the meaning of OA Framework HelloWorld Program and compare the steps to D2K form [where possible]. To keep things simple, only basics will be discussed. Following key Steps were needed for HelloWorld Step 1 Create a new Workspace and a new Project as dictated by Oracle's tutorial. When defining project, you will specify a default package, which in this case was oracle.apps.ak.hello This means the following: - ak is the short name of the Application in Oracle [means fnd_applications.short_name] hello is the name of your project Step 2 Next, you will create a OA Page within hello project Think OA Page as the fmx file itself in D2K. I am saying so because this page gets attached to the form function. This page will be created within hello project, hence the package name oracle.apps.ak.hello.webui Note the webui, it is a convention to have page in webui, means this page represents the Web User Interface You will assign the default AM [OAApplicationModule]. Think of AM "Connection Manager" and "Transaction State Manager" for your page I can't co-relate this to anything in D2k, as there is no concept of Connection Pooling and that D2k is not stateless. Reason being that as soon as you kick off a D2K Form, it connects to a single session of Oracle and sticks to that single Oracle database session. So is not the case in OAF, hence AM is needed. Step 3 You create Region within the Page. · Region is what will store your fields. Text input fields will be of type messageTextInput. Think of Canvas in D2K. You can have nested regions. Stacked Canvas in D2K comes the closest to this component of OA Framework Step 4 Add a button to one of the nested regions The itemStyle should be submitButton, in case you want the page to be submitted when this button is clicked There is no WHEN-BUTTON-PRESSED trigger in OAF. In Framework, you will add a controller java code to handle events like Form Submit button clicks. JDeveloper generates the default code for you. Primarily two functions [should I call methods] will be created processRequest [for UI Rendering Handling] and processFormRequest Think of processRequest as WHEN-NEW-FORM-INSTANCE, though processRequest is very restrictive. Note What is the difference between processRequest and processFormRequest? These two methods are available in the Default Controller class that gets created. processFormRequest This method is commonly used to react/respond to the event that has taken place, for example click of a button. Some examples are if(oapagecontext.getParameter("Cancel") != null) (Do your processing for Cancellation/ Rollback) if(oapagecontext.getParameter("Submit") != null) (Do your validations and commit here) if(oapagecontext.getParameter("Update") != null) (Do your validations and commit here) In the above three examples, you could be calling oapagecontext.forwardImmediately to re-direct the page navigation to some other page if needed. processRequest In this method, usually page rendering related code is written. Effectively, each GUI component is a bean that gets initialised during processRequest. Those who are familiar with D2K forms, something like pre-query may be written in this method. Step 5 In the controller to access the value in field "HelloName" the command is String userContent = pageContext.getParameter("HelloName"); In D2k, we used :block.field. In OAFramework, at submission of page, all the field values get passed into to OAPageContext object. Use getParameter to access the field value To set the value of the field, use OAMessageTextInputBean field HelloName = (OAMessageTextInputBean)webBean.findChildRecursive("HelloName"); fieldHelloName.setText(pageContext,"Setting the default value" ); Note when setting field value in controller: Note 1. Do not set the value in processFormRequest Note 2. If the field comes from View Object, then do not use setText in controller Note 3. For control fields [that are not based on View Objects], you can use setText to assign values in processRequest method Lets take some notes to expand beyond the HelloWorld Project Note 1 In D2K-forms we sort of created a Window, attached to Canvas, and then fields within that Canvas. However in OA Framework, think of Page being fmx/Window, think of Region being a Canvas, and fields being within Regions. This is not a formal/accurate understanding of analogy between D2k and Framework, but is close to being logical. Note 2 In D2k, your Forms fmb file was compiled to fmx. It was fmx file that was deployed on mid-tier. In case of OAF, your OA Page is nothing but a XML file. We call this MDS [meta data]. Whatever name you give to "Page" in OAF, an XML file of the same name gets created. This xml file must then be loaded into database by using XML Importer command. Note 3 Apart from MDS XML file, almost everything else is merely deployed to your mid-tier. Usually this is underneath $JAVA_TOP/oracle/apps/../.. All java files will go underneath java top/oracle/apps/../.. etc. Note 4 When building tutorial, ignore the steps for setting "Attribute Sets". These are not mandatory. Oracle might just have developed their tutorials without including these. Think of these like Visual Attributes of D2K forms Note 5 Controller is where you will write any java code in OA Framework. You can create a Controller per Page or have a different Controller for each of the Regions with the same Page. Note 6 In the method processFormRequest of the Controller, you can access the values of the page by using notation pageContext.getParameter("<fieldname here>"). This method processFormRequest is executed when the OAF Screen/Page is submitted by click of a button. Note 7 Inside the controller, all the Database Related interactions for example interaction with View Objects happen via Application Module. But why so? Because Application Module Manages the transaction state of the Application. OAApplicationModuleImpl oaapplicationmoduleimpl = OAApplicationModuleImpl)oapagecontext.getApplicationModule(oawebbean); OADBTransaction oadbtransaction = OADBTransaction)oaapplicationmoduleimpl.getDBTransaction(); Note 8 In D2K, we have control block or a block based on database view. Similarly, in OA Framework, if the field does not have view Object attached, then it is like a control field. Hence in HelloWorld example, field HelloName is a control field [in D2K terminology]. A view Object can either be based on a view/table, synonym or on a SQL statement. Note 9 I wish to access the fields in multi record block that is based on view Object. Can I do this in Controller? Sure you can. To traverse through those records, do the below · Get the reference to the View Object using (OAViewObject)oapagecontext.getApplicationModule(oawebbean).findViewObject("VO Name Here") · Loop through the records in View Objects using count returned from oaviewobject.getFetchedRowCount() · For each record, fetch the value of the fields within the loop as oracle.jbo.Row row = oaviewobject.getRowAtRangeIndex(loop index here); (String)row.getAttribute("Column name of VO here ");

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CodePlex Daily Summary for Monday, September 03, 2012

CodePlex Daily Summary for Monday, September 03, 2012Popular ReleasesMetodología General Ajustada - MGA: 03.01.03: Cambios Aury: Ajuste del margen del reporte. Visualización de la columna de Supuestos en la parte del módulo de Decisión. Cambios John: Integración de código con cambios enviados por Aury Niño. Generación de instaladores. Soporte técnico por correo electrónico y telefónico.Iveely Search Engine: Iveely Search Engine （0.2.0）: ????ISE?0.1.0??，?????，ISE?0.2.0?????????，???????，????????20???follow?ISE，????，??ISE??????????，??????????，?????????，?????????0.2.0??????，??????????。 Iveely Search Engine ?0.2.0?????????“??????????”，??????，?????????，???????，???????????????????，????、????????????。???0.1.0????????????： 1. ??“????” ??。??????????，?????????，???????????????????。??：????????，????????????，??????????????????。??????。 2. ??“????”??。?0.1.0??????，???????，???????????????，?????????????，????????，?0.2.0?，???????...Thisismyusername's codeplex page.: HTML5 Mulititouch Fruit Ninja Proof of Concept: This is an example of how you could create a game such as Fruit Ninja using HTML5's multitouch capabilities. Sorry this example doesn't have great graphics. If I had my own webpage, I could store some graphics and upload the game there and it might look halfway decent, but since I'm only using a Codeplex page and most mobile devices can't open .zip files, the fruits are just circles. I hope you enjoy reading the source code anyway.GmailDefaultMaker: GmailDefaultMaker 3.0.0.2: Add QQ Mail BugfixSmart Data Access layer: Smart Data access Layer Ver 3: In this version support executing inline query is added. Check Documentation section for detail.TSQL Code Smells Finder: POC 1.01: Proof of concept 1.01 TSQLDomTest.ps1 and Errors.Txt are requiredConfuser: Confuser build 76542: This is a build of changeset 76542.Reactive State Machine: ReactiveStateMachine-beta: TouchStateMachine now supports Microsoft Surface 2.0 SDK. The TouchStateMachine is an extension to the Reactive State Machine. Reactive State Machine uses NuGet for dependency managementSharePoint Column & View Permission: SharePoint Column and View Permission v1.2: Version 1.2 of this project. If you will find any bugs please let me know at enti@zoznam.sk or post your findings in Issue TrackerMihmojsos OS: Mihmojsos OS 3 (Smart Rabbit): !Mihmojsos OS 3 Smart Rabbit Mihmojsos Smart Rabbit is now availableDotNetNuke Translator: 01.00.00 Beta: First release of the project.YNA: YNA 0.2 alpha: Wath's new since 0.1 alpha ? A lot of changes but there are the most interresting : StateManager is now better and faster Mouse events for all YnObjects (Sprites, Images, texts) A really big improvement for YnGroup Gamepad support And the news : Tiled Map support (need refactoring) Isometric tiled map support (need refactoring) Transition effect like "FadeIn" and "FadeOut" (YnTransition) Timers (YnTimer) Path management (YnPath, need more refactoring) Downloads All downloads...Audio Pitch & Shift: Audio Pitch And Shift 5.1.0.2: fixed several issues with streaming modeUrlPager: UrlPager 1.2: Fixed bug in which url parameters will lost after paging; ????????url???bug；Sofire Suite: Sofire v1.5.0.0: Sofire v1.5.0.0 ?? ???????? ?????： 1、?? 2、????EntLib.com????????: EntLib.com???????? v3.0: EntLib eCommerce Solution ???Microsoft .Net Framework?????????????????????。Coevery - Free CRM: Coevery 1.0.0.24: Add a sample database, and installation instructions.Math.NET Numerics: Math.NET Numerics v2.2.1: Major linear algebra rework since v2.1, now available on Codeplex as well (previous versions were only available via NuGet). Since v2.2.0: Student-T density more robust for very large degrees of freedom Sparse Kronecker product much more efficient (now leverages sparsity) Direct access to raw matrix storage implementations for advanced extensibility Now also separate package for signed core library with a strong name (we dropped strong names in v2.2.0) Also available as NuGet packages...Microsoft SQL Server Product Samples: Database: AdventureWorks Databases – 2012, 2008R2 and 2008: About this release This release consolidates AdventureWorks databases for SQL Server 2012, 2008R2 and 2008 versions to one page. Each zip file contains an mdf database file and ldf log file. This should make it easier to find and download AdventureWorks databases since all OLTP versions are on one page. There are no database schema changes. For each release of the product, there is a light-weight and full version of the AdventureWorks sample database. The light-weight version is denoted by ...Christoc's DotNetNuke Module Development Template: DotNetNuke Project Templates V1.1 for VS2012: This release is specifically for Visual Studio 2012 Support, distributed through the Visual Studio Extensions gallery at http://visualstudiogallery.msdn.microsoft.com/ After you build in Release mode the installable packages (source/install) can be found in the INSTALL folder now, within your module's folder, not the packages folder anymore Check out the blog post for all of the details about this release. http://www.dotnetnuke.com/Resources/Blogs/EntryId/3471/New-Visual-Studio-2012-Projec...New ProjectsBPVote4PPT: BPVote For PowerPointCosmo OS: La semplicità in un OSFinancial Analytic Tools: C#.Net Financial Analytic ToolsGeminiMVC: An Open Source CMS written in ASP.net MVC 4 with speed, extensibility, and ease-of-us in mind.JQuery SharePoint Autocomplete People Picker: This JQUery bundle provides an autocomplete people picker based on SharePoint profiles. It can be hosted on the SharePoint itself or on remote applications.Kerbal Space Program PartModule Library: This project is designed to add various functionalities to custom parts for the space program simulation game Kerbal Space Program.KeyboardRemapper: This tool to remaps keys in the keyboard. If you have more than one keyboard or an additional keypad, you can remap the keys of the each keyboard independentlyKHStudent: ??????Localized DataAnnotations with T4 templates: Simplified DataAnnotations localization using T4 templates.MfcLightToolkit: Supports development for small and simple MFC application. Provides asynchronous programming model like .NET, file download, easy control resizing, and so on.Müslüm ÖZTÜRK Code Lib: Test amaçli olusturulan projemdirPolska: Testproject in how a polish grammerprogram can look like.QueueLessApp: Here is the codeRusIS.CMS: aaaSGPS: Projeto de controle de produtos e serviçosStemmersNet: Stemmers pack for .Net FrameworkTrabajo Final de Ingenieria - Javier Vallejos: Tesis Final de la carrera de Ingenieria - Universidad Abierta Interamericana.TSQL Code Smells Finder: TSQL 'smells' findersXNA and Data Driven Design: This project includes links for XNA and Data Driven DesignXNA and System Testing: This project includes code for XNA and System TestingYUGI-AR Project: an open source project for yugioh based augmented reality???????? ? ?????????????: ???? ??????? ??????? ?????????????? ??????????? ?????????? ??? ? ????? ?????? ? ? ??? ??? ????? ? ??? ?????????? ????????????.

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