I've created a new Vaadin (6.6.5) project in eclipse and I've tried to deploy it on JBoss 7.0 but it gives me a GWT ClassNotFoundException
Caused by: java.lang.ClassNotFoundException: com.google.gwt.user.client.ui.HasWidgets from [Module "deployment.test.war:main" from Service Module Loader]
at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:191)
at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:358)
at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:330)
at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:330)
at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:307)
at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:101)
... 64 more
Do I need to do something extra to deploy the gwt libraries?
Seems that some GWT classes in gwt-user.jar required for compiling the Vaadin client side widgetset are loaded by the JBoss7 unnecessarily.
vaadin.jar contains references to gwt-user.jar but it's not required during runtime, only during widgetset compilation time. Still JBoss wants to load these classes causing the problem.
There's a bug report in JBoss for this: http://community.jboss.org/thread/169575?tstart=0
As mentioned there, workaround is to include gwt-user.jar to the deployment package in WEB-INF/lib folder with the vaadin.jar, seems to work.
Vaadin Eclipse plugin creates library dependencies to gwt jar files and generally Eclipse should take care of the runtime classpath when deploying.
As the package name com.google.gwt.user.client suggest this should be in gwt-user.jar.
The gwt-dev.jar should only be needed when compiling client-side code with GWT.
Are you using add-ons? Add-ons (and their dependencies) should be always added to WEB-INF/lib to make the server-side classes available to the application and client-side code available to the GWT compiler.
On possible cause of the problem is (unnecessary) dependency to client-side class which is not available in the server at runtime. So, you might also check your code for unnecessary server-side dependencies to client-side GWT classes (like HasWidgets).
Check your code to ensure that you do not accidentally access this com.google.gwt.** class from your code. As said above, there is no need to deploy gwt libraries in the server.
Vaadin has now published an add-on to fix this, see https://vaadin.com/directory#!addon/vaadin-application-server-class-loader-workaround
Related
I know this question was asked a lot of times, since I searched for hours for a solution, but it was never answered (or at least not for my situation).
I am using Wildfly 8.0 (ex JBoss), so I understand that I do not need to add jstl jars nor JSF jars since the implementation is already shipped with JBoss.
Now even when telling eclipse to use the Wildfly runtime libraries, I get the above error. I checked and the jboss-jstl-api_1.2_spec-1.0.4.Final.jar is part of the library
How can I get through this? I tried putting downloading jstl jars (from https://jstl.java.net/) and putting them in the lib directory but it is not working.
Copying the jars into "lib" works perfectly when I use Tomcat which doesn't have its jstl implementation. But not with Wildfly (maybe because eclipse ignores the jars I put in the lib directory since Wildfly has its own jars? But then why do I get the error in the first place? I am confused).
Thanks to anyone who could help me with this.
Edit: I forgot to precise that even with these errors on all my JSPs, the project builds and works perfectly on the server.
These errors are eclipse specific, it does not recognize the taglibs and displays annoying error messages at taglib declarations and warnings when using these (unknown to eclipse) tags. Plus, I can't use code completion.
Edit: I bypassed the problem, for the moment, by adding standalone myfaces and jstl libraries to the build path. I would like though that eclipse uses the jars available on server side. (For JPA for example I did not need to add the hibernate library to the build path, I simply told eclipse that the JPA implementation si available on server runtime and it worked fine with code completion and everything).
Alright, to not have to add any additional libraries (that are not needed by the server) here's what I had to do in addition to adding the Wildfly runtime library to the project:
Go to Project/Properties/Project Facets/Java Server Faces and chose Library Provided by Target Runtime in the library type (instead of a User Library).
I'm truly disappointed JSF support in eclipse. I'm encountering such caveats all the time.
I'm using JBoss 7.1.1 and even adding JBoss as the Target Runtime of the project didn't help.
The only solution that worked for me, was to define new JSF library inside Eclipse: Window Preferences -> Java -> Build Path -> User Libraries -> click New (pointing to the jsf-impl.jar and jsf-api.jar). And then adding such library to the build path of the project.
It solved all annoying eclipse errors can not find tag library. So it is pretty similar to the #Riccatti first solution.
Btw: answer which I found on the eclipse forum says that this error is usually caused by not existing JSF tag libraries (that are present in jsf-impl.jar) on the classpath.
I have the following issue.
I have a dao library using the atomikos JTA transaction manager.
Also I have a web project that includes that dao library.
And although the tomcat lib folder includes all the required atomikos libraries, I still need to include the atomikos dependency (maven) with scope compile on the library (such that it is packaged along, or at least Eclipse knows it has to be packaged along).
If the library is not packaged along I get Class not found exceptions when deploying under eclipse/STS.
Since the Atomikos libraries are only required for development environments, I don't want these libraries to have scope compile (or runtime).
How can I change my tomcat eclipse setup such that I can set my atomikos dependencies with scope provided in my dao library.
Any suggestions?
Ok I'm having quite some issues setting both jbpm and jboss working together...something as simple as running the jbpm process from a servlet is trunning to be a pain and all because jBoss can't find classes.
I made a Dynamic Web Project and didn't use Maven project so things are cleaner...and because it should work.
I just want to load a jbpmn2.0 from the repository in a servlet and run it using a WorkItemHanlder....but I get this:
java.lang.ClassNotFoundException: org.drools.runtime.process.WorkItemHandler
For some reason jBoss can't find a class from jBPM that should work on JBoss. What I did....and I think it's not the right solution...was add the knowledge-api.jar to the WEB-INF/lib. Although I can now deploy the app when I try to run it I get:
Error Unable to instantiate service for Class 'org.drools.builder.KnowledgeBuilderFactoryService'
I Honestly don't get why is it so hard to make a Jboss Web app using jBpm.
You need to make sure all dependencies are on your classpath, this is the same for all Java applications (not just jbpm) and application servers (not just JBossAS).
Which jars did you add? Depending on which features you are using, there could be quite a number of jars that you need to add. One option would for example would be to extract the jars in the jBPM runtime zip that is part of the jBPM downloads into your WEB-INF/lib.
If you use Maven, you would be able to automatically derive all required jars.
Kris
I just downloaded Netty for a personal client-server-project from here:
http://netty.io/downloads/netty-3.3.0.Final-dist.tar.bz2
On the download page http://netty.io/downloads/ it says there are "no mandatory external dependencies". You only need a JDK 1.5 or higher. So I just set up a java project in eclipse IDE using my 1.6 JDK and got multiple errors saying "import cannot be resolved".
Examples:
org.jboss.logging, com.google, org.osgi, javax.servlet
That tells me that there are actually some external libraries needed. Or am I doing anything wrong?
Can anyone tell me where to find all these libraries since I could not find any clues on the Netty pages where to get them (I know that javax.servlet is part of Tomcat and JBoss AS distribution, but why do they then say that no external libraries are needed).
Are you trying to build netty from source? There's a pom.xml file in the root, implying that netty can be built by maven. You'll find all those dependencies in the pom file. "No mandatory external dependencies" means that you need no jar other than the netty jar to run your application. External dependecies is probably needed for some of the examples, definitively for testing and perhaps for some special, but optional, run time features.
The dependencies are only used for building and are marked as optional. The dependencies are only needed if you want for example use slf4j for logging in netty. Beside this netty can be used within your project without pulling in any third-party dependencies.
When I develop an Axis2 web service on Eclipse, I noticed that Eclipse is automatically copying the classes from the lib folder of Axis2 to the lib folder of the new project. However, not all classes from the lib folder of Axis2 are being copied. Interestingly, the web service runs without any problem when deployed to Tomcat via Eclipse even if some the jars from Axis2 were not copied. Also, when I viewed the temp file of Tomcat, Tomcat seems to generate the jars for the listed modules on modules.list of the web service.
Can someone enlighten me regarding what is happening on this? Why Eclipse doesn't copy all the jars from Axis2? Why can the web service run on Tomcat even without the other jars from Axis2? What are those temp files for? When and why is it being generated?
I tried to run the same project on WebSphere and I am encountering a ClassDefNotFound exception because of the missing jars. My problem was solved when I copied all the Axis2 jars that was not copied by Eclipse to my project. But I'm not comfortable with my solution because Tomcat can run my project even without those jars. Is my solution really the right solution? Or am I missing a configuration setting?
This is just for clarification:
My web service is already running in Axis2. My class loading policy is set to PARENT_LAST. I know that since WebSphere has its own Axis2 configuration, the class loading policy must be set to PARENT_LAST so that WebSphere will use the Axis2 from the project itself. Aside from setting the class loading policy, I did something to make my web service run on WebSphere. I describe what I did above. My question is why such method must be taken?
WebSphere has it's own axis2 configuration as part of its Java EE server spec for JAX-WS. Change your class loading policy to PARENT_LAST and check if that solves your problem.
Edit:
As the original post already states: WebSphere is a Java EE server depending on version it supports its the standard Java JAX-WS web services. Actually web services became part of the standard jdk.
If you use JAX-WS like mentioned in Introduction to JAX-WS or building web services then you don't have to add any 3rd party library for getting your web services running. As soon as you use the non JDK implementation like axis2 you have to package it with your application.
IBM didn't just pack the axis2 into their WAS/JDK, they modified it. I'm not sure what Tomcat delivers, however as long as you use JAX-WS it shouldn't matter. With JAX-WS you don't have any direct import of the org.apache.axis packages. If you use these imports you have to supply the libraries and make sure that yours are loaded.