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  • Python and App Engine project structure

    - by Joel
    Hello, I am relatively new to python and app engine, and I just finished my first project. It consists of several *.py files (usually py file for every page on the site) and respectively temple files for each py file. In addition, I have one big PY file that has many functions that are common to a lot of pages, in I also declared the classes of db.Model (that is the datastore kinds). My question is what is the convention (if there is one) of arranging these files. If I create a model.py with the datastore classes, should it be in different package? Where should I put my template files and all of the py files that handle every page (should they be in the same directory as the one big common PY file)? I have tried to look for MVC and such implementations online but there are very few. Thanks, Joel

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  • How to casue a CppUnit test to fail - from C?

    - by mawg
    I'd like to have an equivalent to CPPUNIT_ASSERT, CPPUNIT_ASSERT_MESSAGE or `CPPUNIT_FAIL' which I can call from some common C code. Our code is a mix of C and C++. Some older apps and those with specific requirements are coded in C and most, especially newer, are coded in C++. However, a lot of project-agnostic, common code, such as memory buffer pools, debug tracing, etc are coded in C. When testing a C++ app in CppUnit, I'd to be able to sprinkle some ASSSERT()s which would cause any running CppUnit test to fail. Maye something like: if testing if running in debugger (Eclipse) then asm("int3"); // stop the debugger, even if no breakpoint at this line else if running CppUnit test - fail the test and move on to next else trace to log file Most of that can be run by wrapping a macro around a few #ifdefs, but I am not sure how I would cause a CppUni test to fail from C code. Can it be done?

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  • How to "interleave" two DataTables.

    - by Brent
    Take these two lists: List 1 Red Green Blue List 2 Brown Red Blue Purple Orange I'm looking for a way to combine these lists together to produce: List 3 Brown Red Green Blue Purple Orange I think the basic rules are these: 1) Insert on top the list any row falling before the first common row (e.g., Brown comes before the first common row, Red); 2) Insert items between rows if both lists have two items (e.g., List 1 inserts Green between Red and Blue); and 3) Insert rows on the bottom if the there's no "between-ness" found in 2 (e.g., List 2 inserts Orange at the bottom). The lists are stored in a DataTable. I'm guessing I'll have to switch between them while iterating, but I'm having a hard time figuring out a method of combining the rows. Thanks for any help. --Brent

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  • Cannot install Apache Web Server on Ubuntu, Amazon WS

    - by Eugene Retunsky
    I enter command apt-get install apache2 --fix-missing (under the root user) and this is what I receive: Reading package lists... Done Building dependency tree Reading state information... Done The following extra packages will be installed: apache2-mpm-worker apache2-utils apache2.2-bin apache2.2-common libapr1 libaprutil1 libaprutil1-dbd-sqlite3 libaprutil1-ldap ssl-cert Suggested packages: apache2-doc apache2-suexec apache2-suexec-custom openssl-blacklist The following NEW packages will be installed: apache2 apache2-mpm-worker apache2-utils apache2.2-bin apache2.2-common libapr1 libaprutil1 libaprutil1-dbd-sqlite3 libaprutil1-ldap ssl-cert 0 upgraded, 10 newly installed, 0 to remove and 36 not upgraded. Need to get 2,945 kB/3,141 kB of archives. After this operation, 10.4 MB of additional disk space will be used. Do you want to continue [Y/n]? y Err http://us-west-1.ec2.archive.ubuntu.com/ubuntu/ oneiric-updates/main apache2.2-bin i386 2.2.20-1ubuntu1.1 404 Not Found [IP: 10.161.51.124 80] Err http://security.ubuntu.com/ubuntu/ oneiric-security/main apache2.2-bin i386 2.2.20-1ubuntu1.1 404 Not Found [IP: 91.189.92.167 80] Err http://security.ubuntu.com/ubuntu/ oneiric-security/main apache2-utils i386 2.2.20-1ubuntu1.1 404 Not Found [IP: 91.189.92.167 80] Err http://security.ubuntu.com/ubuntu/ oneiric-security/main apache2.2-common i386 2.2.20-1ubuntu1.1 404 Not Found [IP: 91.189.92.167 80] Err http://security.ubuntu.com/ubuntu/ oneiric-security/main apache2-mpm-worker i386 2.2.20-1ubuntu1.1 404 Not Found [IP: 91.189.92.167 80] Err http://security.ubuntu.com/ubuntu/ oneiric-security/main apache2 i386 2.2.20-1ubuntu1.1 404 Not Found [IP: 91.189.92.167 80] Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/a/apache2/apache2.2-bin_2.2.20-1ubuntu1.1_i386.deb 404 Not Found [IP: 91.189.92.167 80] Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/a/apache2/apache2-utils_2.2.20-1ubuntu1.1_i386.deb 404 Not Found [IP: 91.189.92.167 80] Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/a/apache2/apache2.2-common_2.2.20-1ubuntu1.1_i386.deb 404 Not Found [IP: 91.189.92.167 80] Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/a/apache2/apache2-mpm-worker_2.2.20-1ubuntu1.1_i386.deb 404 Not Found [IP: 91.189.92.167 80] Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/a/apache2/apache2_2.2.20-1ubuntu1.1_i386.deb 404 Not Found [IP: 91.189.92.167 80] Unable to correct missing packages. E: Aborting install. Any help is appreciated.

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  • Can't use FAXCOMEXLib in VS 2010 anymore?

    - by Sam
    I'm just in the process of moving from Visual Studio 2008 to Visual Studio 2010. One of my projects use the Microsoft Fax Service Extended COM Type Library. After converting the project to VS 2010 I get the following compiler error: C:\Windows\Microsoft.NET\Framework\v4.0.30319\Microsoft.Common.Targets(1558,9): error MSB3648: The Keycontainer-path "VS_KEY_812A0248FF872DEC" ist invalid. KeyContainer must point to an existing file. C:\Windows\Microsoft.NET\Framework\v4.0.30319\Microsoft.Common.Targets(1558,9): warning MSB3283: Wrapperassembly for type library "FAXCOMEXLib" not found. I tried to remove FAXCOMEXLib from the project and adding it again, but it did not help. I got a similar problem with other COM references. How do I resolve this?

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  • CSS file pathing problem

    - by Alan Harris-Reid
    Hi there, When designing a HTML template in my favorite editor (TextPad at the moment) I can view my code in a browser by pressing F11 or the appropriate toolbar button. I have my common css rules in a separate file so my HTML contains the code: <link rel="stylesheet" href="commoncss.css" type="text/css"> This works when the .css file is in the same folder as the .html file, or if I fully path the .css file in the href property, eg. ///c:/mycssfolder/commoncss.css However, in a 'live' situation I want the .css file to reside in a common folder which is accessible from a number of .html files (eg. href='css/commoncss.css', where the css folder is configured at web-server level). How can I achieve this design vs. live dilemma without copying css file to all .html folders (and all the maintenance headaches that comes with it)? I am using Python 3.1 with Jinja2, but I guess this problem is applicable across any language and template-engine. Any help would be appreciated. Alan

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  • WindowsIdentity Token in Legacy ASP

    - by Max Schmeling
    I've created a .Net library at work that is used by all of our developers. The security part of it uses Microsoft AzMan for the security backend. In order to create a security (AzMan) ClientContext I have to pass it a token value (as a uint). This is all fine an dandy until I needed to make a COM wrapper for our common library so some of our legacy pages could take advantage of it without being rewritten for now. I cannot figure out how to get the token value to pass to AzMan from legacy ASP. The COM wrapper is setup to run as a COM Server and runs as a specific user that we use here for all COM objects, therefor the common library can't just pull the identity using .Net. Any ideas?

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  • How to find the longest continuous subsequence whose reverse is also a subsequence

    - by iecut
    Suppose I have a sequence x1,x2,x3.....xn, and I want to find the longest continuous subsequence xi,xi+1,xi+2......xi+k, whose reverse is also a subsequence of the given sequence. And if there are multiple such subsequences, then I also have to find the first. ex:- consider the sequences: abcdefgedcg here i=3 and k=2 aabcdddd here i=5, k=3 I tried looking at the original longest common subsequence problem, but that is used to compare the two sequences to find the longest common subsequence.... but here is only one sequence from which we have to find the subsequences. Please let me know what is the best way to approach this problem, to find the optimal solution.

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  • Shell script [Expected end of line, etc. but found unknown token]

    - by rockinthesixstring
    I'm trying to build a Synergy AutoStart script as per this article, the shell is giving me the error Syntax Error Expected end of line, etc. but found unknown token Here is the script I'm working on... #!/bin/sh . /etc/rc.common run=(/usr/local/bin/synergyc -n $(hostname -s) -1 -f 192.168.0.108) KeepAlive () { proc=${1##*/} while [ -x "$1" ] do if ! ps axco command | grep -q "^${proc}\$" then "$@" fi sleep 3 done } StartService () { ConsoleMessage "Starting Synergy" KeepAlive "${run[@]}" & } StopService () { return 0 } RestartService () { return 0 } RunService "$1" And when the error is thrown, the "period" is highlighted on this line . /etc/rc.common Is there something I'm missing here?

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  • gem install of mongrel

    - by atlantis
    I initiated myself into rails development yesterday. I installed ruby 1.9.1 , rubygems and rails. Running 'gem install mongrel' worked fine and ostensibly installed mongrel too. I am slightly puzzled because script/server starts webrick by default 'which mongrel' returns nothing 'locate mongrel' returns lots of entries like . /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1 /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib/mongrel . . . /usr/local/bin/mongrel_rails /usr/local/lib/ruby/gems/1.9.1/cache/mongrel-1.1.5.gem /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/evented_mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/swiftiplied_mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/evented_mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/swiftiplied_mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/mongrel-1.1.5 . . . Does look like I have mongrel installed (both the default installation and my custom install). So why doesn't which mongrel return something. Also trying to reinstall mongrel using 'gem install mongrel' returns throws its own set of exceptions : Building native extensions. This could take a while... ERROR: Error installing mongrel: ERROR: Failed to build gem native extension. /usr/local/bin/ruby extconf.rb install mongrel checking for main() in -lc... yes creating Makefile make gcc -I. -I/usr/local/include/ruby-1.9.1/i386-darwin9.7.0 -I/usr/local/include/ruby-1.9.1/ruby/backward -I/usr/local/include/ruby-1.9.1 -I. -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -fno-common -D_XOPEN_SOURCE=1 -O2 -g -Wall -Wno-parentheses -fno-common -pipe -fno-common -o http11.o -c http11.c http11.c: In function 'http_field': http11.c:77: error: 'struct RString' has no member named 'ptr' http11.c:77: error: 'struct RString' has no member named 'len' http11.c:77: warning: left-hand operand of comma expression has no effect http11.c:77: warning: statement with no effect http11.c: In function 'header_done': http11.c:172: error: 'struct RString' has no member named 'ptr' http11.c:174: error: 'struct RString' has no member named 'ptr' http11.c:176: error: 'struct RString' has no member named 'ptr' http11.c:177: error: 'struct RString' has no member named 'len' http11.c: In function 'HttpParser_execute': http11.c:298: error: 'struct RString' has no member named 'ptr' http11.c:299: error: 'struct RString' has no member named 'len' make: *** [http11.o] Error 1

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  • `gem install mongrel` fails with ruby 1.9.1

    - by atlantis
    I initiated myself into rails development yesterday. I installed ruby 1.9.1, rubygems and rails. Running gem install mongrel worked fine and ostensibly installed mongrel too. I am slightly puzzled because: script/server starts webrick by default which mongrel returns nothing locate mongrel returns lots of entries like /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1 /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib/mongrel . . . /usr/local/bin/mongrel_rails /usr/local/lib/ruby/gems/1.9.1/cache/mongrel-1.1.5.gem /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/evented_mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/swiftiplied_mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/evented_mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/swiftiplied_mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/mongrel-1.1.5 . . . Does look like I have mongrel installed (both the default installation and my custom install). So why doesn't which mongrel return something. Also trying to reinstall mongrel using gem install mongrel returns throws its own set of exceptions: Building native extensions. This could take a while... ERROR: Error installing mongrel: ERROR: Failed to build gem native extension. /usr/local/bin/ruby extconf.rb install mongrel checking for main() in -lc... yes creating Makefile make gcc -I. -I/usr/local/include/ruby-1.9.1/i386-darwin9.7.0 -I/usr/local/include/ruby-1.9.1/ruby/backward -I/usr/local/include/ruby-1.9.1 -I. -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -fno-common -D_XOPEN_SOURCE=1 -O2 -g -Wall -Wno-parentheses -fno-common -pipe -fno-common -o http11.o -c http11.c http11.c: In function 'http_field': http11.c:77: error: 'struct RString' has no member named 'ptr' http11.c:77: error: 'struct RString' has no member named 'len' http11.c:77: warning: left-hand operand of comma expression has no effect http11.c:77: warning: statement with no effect http11.c: In function 'header_done': http11.c:172: error: 'struct RString' has no member named 'ptr' http11.c:174: error: 'struct RString' has no member named 'ptr' http11.c:176: error: 'struct RString' has no member named 'ptr' http11.c:177: error: 'struct RString' has no member named 'len' http11.c: In function 'HttpParser_execute': http11.c:298: error: 'struct RString' has no member named 'ptr' http11.c:299: error: 'struct RString' has no member named 'len' make: *** [http11.o] Error 1

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  • Is it normal for a programmer with 2 years experience to take a long time to code simple programs?

    - by ajax81
    Hi all, I'm a relatively new programmer (18 months on the scene), and I'm finally getting to the point where I'm comfortable accepting projects and developing solutions under minimal supervision. Unfortunately, this also means that I've become acutely aware of my performance shortfalls, the most prevalent of which is the amount of time it takes me to develop, test, and submit algorithms for review. A great example of what I'm talking about occurred this week when I was tasked with developing a simple XML web service (asp.net 3.5) callable via client-side JavaScript, that accepts a single parameter and returns a dataset output to a modal window (please note this is the first time I've had to develop a web service and have had ZERO experience creating/consuming them...let alone calling them from JS client side). Keeping a long story short -- I worked on it for 4 days straight, all day each day, for a grand total of 36 hours, not including the time I spent dwelling on the problem in the shower, the morning commute, and laying awake in bed at night. I learned a great deal about web services and xml/json/javascript...but was called in for a management review to discuss the length of time it took me to develop the solution. In the meeting, I was praised for the quality of my work and was in fact told that my effort was commendable. However, they (senior leads and pm's) weren't impressed with the amount of time it took me to develop the solution and expressed that they would have liked to see the solution in roughly 1/3 of the time it took me. I guess what concerns me the most is that I've identified this pattern as common for myself. Between online videos, book research, and trial/error coding...if its something I haven't seen before, I can spend up to two weeks on a problem that seems to only take the pros in the videos moments to code up. And of course, knowing that management isn't happy with this pattern has shaken me up a bit. To sum up, I have some very specific questions I'd like to ask, and would greatly appreciate your objective professional feedback. Is my experience as a junior programmer common among new developers? Or is it possible that I'm just not cut out for the work? If you suspect that my experience is not common and that there may be an aptitude issue, do you have any suggestions/solutions that I could propose to management to help bring me up to speed? Do seasoned, professional programmers ever encounter knowledge barriers that considerably delay deliverables? When you started out in the industry, did you know how to "do it all"? If not, how long did it take you to be perceived as "proficient"? Was it a natural progression of trial and error, or was there a particular zen moment when you knew you had achieved super saiyen power level? Anyways, thanks for taking the time to read my question(s). I don't know if this is the right place to ask for professional career guidance, but I greatly appreciate your willingness to help me out. Cheers, Daniel

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  • What Does OSGi Solve?

    - by Pablo Fernandez
    I've read on wikipedia and other sites about OSGi, but I don't really see the big picture. It says that it's a component based platform, and that you can reload modules at runtime. Also the "practical example" given everywhere is the Eclipse Plugin Framework. My questions are: 1) What is the CLEAR and SIMPLE definition of OSGi? 2) What COMMON PROBLEMS does it solve? By "common problems" I mean problems we face everyday, like "what can OSGi do for making our jobs more efficient/fun/simple" Thanks.

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  • How to publish multiple jar files to maven on a clean install

    - by Abhijit Hukkeri
    I have a used the maven assembly plugin to create multiple jar from one jar now the problem is that I have to publish these jar to the local repo, just like other maven jars publish by them self when they are built maven clean install how will I be able to do this here is my pom file <project> <parent> <groupId>parent.common.bundles</groupId> <version>1.0</version> <artifactId>child-bundle</artifactId> </parent> <modelVersion>4.0.0</modelVersion> <groupId>common.dataobject</groupId> <artifactId>common-dataobject</artifactId> <packaging>jar</packaging> <name>common-dataobject</name> <version>1.0</version> <dependencies> </dependencies> <build> <plugins> <plugin> <groupId>org.jibx</groupId> <artifactId>maven-jibx-plugin</artifactId> <version>1.2.1</version> <configuration> <directory>src/main/resources/jibx_mapping</directory> <includes> <includes>binding.xml</includes> </includes> <verbose>false</verbose> </configuration> <executions> <execution> <goals> <goal>bind</goal> </goals> </execution> </executions> </plugin> <plugin> <artifactId>maven-assembly-plugin</artifactId> <executions> <execution> <id>make-business-assembly</id> <phase>package</phase> <goals> <goal>single</goal> </goals> <configuration> <appendAssemblyId>false</appendAssemblyId> <finalName>flight-dto</finalName> <descriptors> <descriptor>src/main/assembly/car-assembly.xml</descriptor> </descriptors> <attach>true</attach> </configuration> </execution> <execution> <id>make-gui-assembly</id> <phase>package</phase> <goals> <goal>single</goal> </goals> <configuration> <appendAssemblyId>false</appendAssemblyId> <finalName>app_gui</finalName> <descriptors> <descriptor>src/main/assembly/bike-assembly.xml</descriptor> </descriptors> <attach>true</attach> </configuration> </execution> </executions> </plugin> </plugins> </build> </project> Here is my assembly file <assembly> <id>app_business</id> <formats> <format>jar</format> </formats> <baseDirectory>target</baseDirectory> <includeBaseDirectory>false</includeBaseDirectory> <fileSets> <fileSet> <directory>${project.build.outputDirectory}</directory> <outputDirectory></outputDirectory> <includes> <include>com/dataobjects/**</include> </includes> </fileSet> </fileSets> </assembly>

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  • Spring transaction : Transaction not active

    - by Videanu Adrian
    i develop a app using struts2, spring 3.1, Jpa2 and Hibernate. From Spring i use transactions and IoC. so, i have an ajax code block that calls for a struts2 action every second (this is happening for every user that is logged into application (simultaneous users are around 20-30 at a time)). this action name is PopupAction public class PopupAction extends VActionBase implements ServletRequestAware { private static final long serialVersionUID = -293004532677112584L; private iIntermedService intermedService; private HttpServletRequest servletRequest; @Override public String execute() { Integer agentId = (Integer) session.get("USER_AGENT_ID"); Intermed iObj; try { iObj = intermedService.getIntermed(agentId,locationsString); } catch (Exception e) { logger.error("Cannot get Intermed!!! "+e.getMessage()); return ERROR; } return SUCCESS; } } and then i have the service class : @Transactional(readOnly=true) public class IntermedServiceImpl extends GenericIService<Intermed, Integer> implements iIntermedService { @Override public Intermed getIntermed (int agentId,String queueIds) throws Exception { Intermed intermedObj = null; //TODO - find a better implementation for this queueIds parameter!!!! try{ String sql = "SELECT i FROM bla bla bla.....)"; Query q = this.em.createQuery(sql); List<Intermed> iList = q.getResultList(); if (iList.size() == 1){ intermedObj = (Intermed) iList.get(0); //get latest object from DB em.refresh(intermedObj); } }catch(Exception e){ e.printStackTrace(); logger.error(e.getCause()+e.getMessage()); throw e; } return intermedObj; } } here is the spring configuration : <bean id="emfI" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"> <property name="dataSource" ref="inboundDS" /> <property name="persistenceUnitName" value="I2PU"/> <!-- GlassFish load-time weaving setup --> <property name="loadTimeWeaver"> <bean class="org.springframework.instrument.classloading.glassfish.GlassFishLoadTimeWeaver"/> </property> </bean> <tx:annotation-driven transaction-manager="txManagerI" /> <tx:advice id="txManagerInboundAdvice" transaction-manager="txManagerI"> <tx:attributes> <tx:method name="*" rollback-for="java.lang.Exception"/> </tx:attributes> </tx:advice> I have names for transactionManager because i have 3 datasources and 3 transaction managers. the problem is that my glassfish logs are full of messages like these: -- removed in order to be able to add more recent logs -- So the cause is : Caused by: java.lang.IllegalStateException: Transaction not active. But i have no idea what can cause this. Any help ? thanks Updates So i have added to @Transactional annotation the transaction manager name that he has to use, but this still does not solved my problem. I have captured a log from the time that the transaction is created until i got that exception: 2012-02-08T15:08:55.954+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractBeanFactory.java:245) - Returning cached instance of singleton bean 'txManagerVA' 2012-02-08T15:08:55.962+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:365) - Creating new transaction with name [xxx.vs.common.services.inbound.IntermedServiceImpl.getIntermed]: PROPAGATION_REQUIRED,ISOLATION_DEFAULT,readOnly; '',-java.lang.Exception 2012-02-08T15:08:55.967+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (JpaTransactionManager.java:368) - Opened new EntityManager [org.hibernate.ejb.EntityManagerImpl@edf83f9] for JPA transaction 2012-02-08T15:08:55.976+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (JpaTransactionManager.java:400) - Exposing JPA transaction as JDBC transaction [org.springframework.orm.jpa.vendor.HibernateJpaDialect$HibernateConnectionHandle@725b979b] 2012-02-08T15:08:55.977+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:193) - Bound value [org.springframework.jdbc.datasource.ConnectionHolder@4fb57177] for key [com.sun.gjc.spi.jdbc40.DataSource40@75fa4851] to thread [thread-pool-1-80(80)] 2012-02-08T15:08:55.978+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:193) - Bound value [org.springframework.orm.jpa.EntityManagerHolder@112c6483] for key [org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean@47d4f12f] to thread [thread-pool-1-80(80)] 2012-02-08T15:08:55.979+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:272) - Initializing transaction synchronization 2012-02-08T15:08:55.980+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionAspectSupport.java:362) - Getting transaction for [xxx.vs.common.services.inbound.IntermedServiceImpl.getIntermed] 2012-02-08T15:08:55.983+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (ExtendedEntityManagerCreator.java:423) - Starting resource local transaction on application-managed EntityManager [org.hibernate.ejb.EntityManagerImpl@46d002f4] 2012-02-08T15:08:55.984+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:193) - Bound value [org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerSynchronization@797add43] for key [org.hibernate.ejb.EntityManagerImpl@46d002f4] to thread [thread-pool-1-80(80)] 2012-02-08T15:08:55.986+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (ExtendedEntityManagerCreator.java:400) - Joined local transaction 2012-02-08T15:08:55.991+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionAspectSupport.java:391) - Completing transaction for [xxx.vs.common.services.inbound.IntermedServiceImpl.getIntermed] 2012-02-08T15:08:55.992+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:922) - Triggering beforeCommit synchronization 2012-02-08T15:08:55.994+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:935) - Triggering beforeCompletion synchronization 2012-02-08T15:08:56.001+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:243) - Removed value [org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerSynchronization@797add43] for key [org.hibernate.ejb.EntityManagerImpl@46d002f4] from thread [thread-pool-1-80(80)] 2012-02-08T15:08:56.002+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:752) - Initiating transaction commit 2012-02-08T15:08:56.003+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (JpaTransactionManager.java:507) - Committing JPA transaction on EntityManager [org.hibernate.ejb.EntityManagerImpl@edf83f9] 2012-02-08T15:08:56.008+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:948) - Triggering afterCommit synchronization 2012-02-08T15:08:56.010+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:964) - Triggering afterCompletion synchronization 2012-02-08T15:08:56.011+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:331) - Clearing transaction synchronization 2012-02-08T15:08:56.012+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:243) - Removed value [org.springframework.orm.jpa.EntityManagerHolder@112c6483] for key [org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean@47d4f12f] from thread [thread-pool-1-80(80)] 2012-02-08T15:08:56.021+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:243) - Removed value [org.springframework.jdbc.datasource.ConnectionHolder@4fb57177] for key [com.sun.gjc.spi.jdbc40.DataSource40@75fa4851] from thread [thread-pool-1-80(80)] 2012-02-08T15:08:56.021+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (JpaTransactionManager.java:593) - Closing JPA EntityManager [org.hibernate.ejb.EntityManagerImpl@edf83f9] after transaction 2012-02-08T15:08:56.022+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (EntityManagerFactoryUtils.java:343) - Closing JPA EntityManager 2012-02-08T15:08:56.023+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|ERROR [thread-pool-1-80(80)] (PopupAction.java:39) - Cannot get Intermed!!! Transaction not active; nested exception is java.lang.IllegalStateException: Transaction not active 2012-02-08T15:08:56.024+0200|SEVERE||_ThreadID=184;_ThreadName=Thread-5;|org.springframework.dao.InvalidDataAccessApiUsageException: Transaction not active; nested exception is java.lang.IllegalStateException: Transaction not active at org.springframework.orm.jpa.EntityManagerFactoryUtils.convertJpaAccessExceptionIfPossible(EntityManagerFactoryUtils.java:298) at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:106) at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerSynchronization.convertException(ExtendedEntityManagerCreator.java:501) at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerSynchronization.afterCommit(ExtendedEntityManagerCreator.java:481) at org.springframework.transaction.support.TransactionSynchronizationUtils.invokeAfterCommit(TransactionSynchronizationUtils.java:133) at org.springframework.transaction.support.TransactionSynchronizationUtils.triggerAfterCommit(TransactionSynchronizationUtils.java:121) at org.springframework.transaction.support.AbstractPlatformTransactionManager.triggerAfterCommit(AbstractPlatformTransactionManager.java:950) at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:796) at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:723) at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:393) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:120) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202) at $Proxy325.getIntermed(Unknown Source) at xxx.vs.common.actions.PopupAction.execute(PopupAction.java:37) at sun.reflect.GeneratedMethodAccessor1581.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:453) at com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:292) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:255) at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:256) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:176) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265) at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:211) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:211) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:190) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:90) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:243) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:145) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:171) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:176) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:192) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:187) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at xxx.vs.common.utils.AuthenticationInterceptor.intercept(AuthenticationInterceptor.java:78) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at com.googlecode.sslplugin.interceptors.SSLInterceptor.intercept(SSLInterceptor.java:128) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249) at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54) at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:510) at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77) at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:217) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:279) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175) at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595) at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98) at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91) at org.apache.catalina 2012-02-08T15:08:56.024+0200|SEVERE||_ThreadID=184;_ThreadName=Thread-5;|.core.StandardHostValve.invoke(StandardHostValve.java:162) at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:330) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231) at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:174) at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828) at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725) at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019) at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225) at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137) at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104) at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90) at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79) at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54) at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59) at com.sun.grizzly.ContextTask.run(ContextTask.java:71) at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532) at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513) at java.lang.Thread.run(Thread.java:679) Caused by: java.lang.IllegalStateException: Transaction not active at org.hibernate.ejb.TransactionImpl.commit(TransactionImpl.java:69) at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerSynchronization.afterCommit(ExtendedEntityManagerCreator.java:478) ... 93 more so again..... any ideea ?

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  • .NET : Targeting the runtime

    - by contactmatt
    I'm starting to read in-depth on the .NET framework, and its Common Language Runtime. I'm reading a .NET overview by Microsoft and I'm not sure what is meant by this statement. Code that targets the runtime is known as managed code, while code that does not target the runtime is known as unmanaged code. How do you target the Common Language Runtime? I know its defaulted when developing in Visual Studio, but how would you specifically target the CLR? What code when developing a .NET application wouldn't target the CLR, and thereby be called unmanaged code?

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  • asp.net MVC Partial Views how to initialise javascript

    - by Simon G
    Hi, I have an edit form that uses an ajax form to submit to the controller. Depending on the data submitted I redirect the user to one of two pages (by returning a partial view). Both pages rely on javascript/jquery and neither use anything common between the pages. What is the best way to initialise these javascripts on each page? I know there is the AjaxOption OnComplete but both pages are quite dynamic depending on the Model passed and I would rather keep the javascript for both pages seperate rather than having a common method. Thanks

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  • [Java] Form data transition into entity beans to persist them by the server side ORM

    - by cscsaba242
    Hello guys, Is there any good explanation or tutorial which describes the common way how can we create entity beans from the received data of the form ? The main reason of my question the treating the received ids (e.g id of country,city and so forth) which is the way from the id to entity ? Example: ................Client side form username:String countryid:Integer (could be a drop down) ................Server side entities public class UserBean { String username; CountryBean Country; } public class CountryBean { String cityname; Integer id; } ............................................ Maybe the question is dependent of the used technology, but I guess there is a very common way. I would like to comprehend the conventional approach of this problem. (For the sake of the completeness I would like to save the form data (received by Stripes) by JPA) Thanks advance. cscsaba242

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  • How reliable is HTTP compression using gzip?

    - by Liam
    YSlow has suggested that I use HTTP compression to improve the performance of my site. However, as noted by Yahoo that are some problems. There are known issues with browsers and proxies that may cause a mismatch in what the browser expects and what it receives with regard to compressed content. Fortunately, these edge cases are dwindling as the use of older browsers drops off. The Apache modules help out by adding appropriate Vary response headers automatically. I understand that the most common problem occurs with IE6 behind a proxy. But how common are these problems today? To quantify it, roughly what percentage of web users experience bugs with HTTP compression?

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  • WCF - Beginners question on Address (of ABC)

    - by Lijo
    Hi Team, I am new to WCF. Following is a question on WCF. Suppose, I have a service defined as follows. The host has two addresses. I usually click on the base address http://.... to generate proxy. When the proxy is generated, will it have address of http alone? How can I generate a proxy with net.tcp. Is there any article that explains the use of net.tcp with local host and ASP.NET? service name="XXX.RRR.Common.ServiceLayer.MySL" behaviorConfiguration="returnFaults" endpoint contract="XXX.RRR.Common.ServiceLayer.IMySL" binding="netTcpBinding" bindingConfiguration="MessagingBinding" behaviorConfiguration="LargeEndpointBehavior"/ host baseAddresses add baseAddress="net.tcp://localhost:86/XXX/RRR/ManagerService" add baseAddress="http://localhost:76/XXX/RRR/ManagerService" baseAddresses host /service Thanks Lijo

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  • asp.net form validation. Server-side or client-side

    - by Jeroen
    Here's (i think) an interesting question. With AJAX more and more common i feel more and more like doing all form validation server-side. Picture a registration form pre-AJAX. You have all your validation client-side using the common asp validation controls and validation summery...except...checking username availability, check emailadress availability, captcha and what not. So you end up with 2 kinds of validation and so presenting the user with 2 different UI's at 2 different moments. 2 words come to my mind. Ugly. Inconsistent. So here's the question. Why not do all the validation server-side (using AJAX or not). (I'm not using JQuery yet, should i?)

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  • How do I create SEO-Friendly urls in ASP.Net-MVC

    - by blesh
    I'm getting myself acquainted with ASP.Net-MVC, and I was trying to accomplish some common tasks I've accomplished in the past with webforms and other functionality. On of the most common tasks I need to do is create SEO-friendly urls, which in the past has meant doing some url rewriting to build the querystring into the directory path. for example: www.somesite.com/productid/1234/widget rather than: www.somesite.com?productid=1234&name=widget What method do I use to accomplish this in ASP.Net-MVC? I've search around, and all I've found is this, which either I'm not understanding properly, or doesn't really answer my question: http://stackoverflow.com/questions/734583/seo-urls-with-asp-net-mvc

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  • Trouble with using ActiveX control in .net windows application

    - by alex dee
    C#, visual studio 2005 I have several 3rd party activeX control. I need to use them in my .net windows application. These controls are graphical. I created a wrapper with aximp.exe for them. But it seems that something wrong. When I call some methods of wrapped activeX control == targetinvocativeexception occured. Or visual studio writes "you are attempting to write or read protected memory". I know that something wrong. But what is exactly wrong - i don't know. I find out about method CreateControl() or STAthread attribute. but it doesn't help me. What is the common problem and common solution for my type of problem ? These activex control from big and trusted company, other developers work with them.

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  • Fairness: Where can it be better handled?

    - by Srinivas Nayak
    Hi, I would like to share one of my practical experience with multiprogramming here. Yesterday I had written a multiprogram. Modifications to sharable resources were put under critical sections protected by P(mutex) and V(mutex) and those critical section code were put in a common library. The library will be used by concurrent applications (of my own). I had three applications that will use the common code from library and do their stuff independently. my library --------- work_on_shared_resource { P(mutex) get_shared_resource work_with_it V(mutex) } --------- my application ----------- application1 { *[ work_on_shared_resource do_something_else_non_ctitical ] } application2 { *[ work_on_shared_resource do_something_else_non_ctitical ] } application3 { *[ work_on_shared_resource ] } *[...] denote a loop. ------------ I had to run the applications on Linux OS. I had a thought in my mind, hanging over years, that, OS shall schedule all the processes running under him with all fairness. In other words, it will give all the processes, their pie of resource-usage equally well. When first two applications were put to work, they run perfectly well without deadlock. But when the third application started running, always the third one got the resources, but since it is not doing anything in its non-critical region, it gets the shared resource more often when other tasks are doing something else. So the other two applications were found almost totally halted. When the third application got terminated forcefully, the previous two applications resumed their work as before. I think, this is a case of starvation, first two applications had to starve. Now how can we ensure fairness? Now I started believing that OS scheduler is innocent and blind. It depends upon who won the race; he got the largest pie of CPU and resource. Shall we attempt to ensure fairness of resource users in the critical-section code in library? Or shall we leave it up to the applications to ensure fairness by being liberal, not greedy? To my knowledge, adding code to ensure fairness to the common library shall be an overwhelming task. On the other hand, believing on the applications will also never ensure 100% fairness. The application which does a very little task after working with shared resources shall win the race where as the application which does heavy processing after their work with shared resources shall always starve. What is the best practice in this case? Where we ensure fairness and how? Sincerely, Srinivas Nayak

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