We Keep Coding

WFLYEE0040: A component named '...' is already defined in this module

I get this error in a Java maven project. The weird thing is, it doesn't appear on every machine so I assume it has something to do with a configuration issue.
The class RoleKeyCacheImpl is a #Startup #Singleton:
#Startup
#Singleton
public class RoleKeyCacheImpl implements RoleKeyCache { ... }
That's the error Wildfly triggers when deploying the service.
Caused by: java.lang.IllegalArgumentException: WFLYEE0040: A component
named 'RoleKeyCacheImpl' is already defined in this module at
org.jboss.as.ee.component.EEModuleDescription.addComponent(EEModuleDescription.java:167)
at
org.jboss.as.ejb3.deployment.processors.EJBComponentDescriptionFactory.addComponent(EJBComponentDescriptionFactory.java:58)
I've tried:
installing a new Wildfly (V10, V13) on the same machine -> doesn't help
installing a completely new Eclipse on this machine -> doesn't help
cleaning & rebuilding all related projects
making sure the deployments-folder is empty and doesn't contain old versions of the same WAR
read the related question here which also didn't help (they use Spring): A component named 'XXX' is already defined in this module in JBoss 7.1.1
read and tried this q&a: Wrong dependencies with EJB in JBoss Wildfly (server-clean) -> doesn't help
deleted and rebuilt the local maven rep (".m2") -> no effect
checking out the same source on another computer -> does work on one machine, on another it gives the same error
I have absolutely no clue what the issue is or even could be. On one machine, we check it out and it runs without errors. On others, the exact same error happens.
Does anybody have an idea?

I had this same issue multiple times with EAP 7.1 and now again with WildFly 21.0.0. I know by experience this is an issue caused by Eclipse who tries to deploy automatically to a configured WildFly instance. During the deployment (or undeployment) some concurrent file issue arises and files who should be removed, are still on the filesystem, causing this error that a component is already defined.
In fact it is not already defined, it is just WildFly that is confused because it finds in his temporary directories some old files which shouldn't be there and reference your exact same component.
Solution: remove in the WildFly standalone directory the content in the 'deployments' directory and the 'tmp' directory. Rest assured, all what is there is okay to remove safely. Reboot and the error message will be gone ;-)

You should pay attention to not have two #Stateless EJB annotations on top of two classes with the same name - in the same module.
You may differentiate them by using the name attribute in the annotation and put different values in each class

Looks like the class already exists. Check if it does...you may have to rewrite that part of EEModuleDescription to use its own private methods (which would be what you would write) rather than overriding methods in RoleKeyCacheImpl. If the class actually does not exist then right-click on the project -> Maven 2 Tools -> Generate Eclipse Artifacts (Check for Updates). That will regenerate all of the dependencies that the project uses. Also please be sure that you have not added any new projects to the classpath by mistake as that may also cause this error.

I just ran into this today when a colleague added a maven dependency.
Turns out this dependency was a jar with a nasty classpath entry or "../" in the manifest.
I edited the jar's manifest.mf that was cached in my local maven repository using 7-zip and removed the "../" classpath entry.
Then re-packaged my war file (maven clean install) and bingo, it works!
In my case it was caused by org.libreoffice jurt version 5.4.2 (but other versions I checked also have the classpath nastiness).
Unfortunately I was lucky we pinpointed it to a dependency, YMMV!

Data directory in elastic search created inside project folder

I am using Java API (maven project) for elastic search. I configured elasticsearch.yml for path.data field as one of the directories. But when I run my code for indexing, in addition to the folder mentioned in config yml file, it also creates a /data/ directory inside the root of the project folder. I am unable to understand why it do so. Can someone please help.
In elasticsearch.yml
path.data: /data/servers/es.data
Thanks.

I also got this issue. In my case (I use Spring Boot) I think the issue is, I forgot to define a bean of org.elasticsearch.client.Client. So I think Spring generated a Client bean and 'made' an elasticsearch DB in my project folder.
Hope this helps someone! Cheers

Failed to import bean definitions from URL location [classpath:applicationContext-core.xml]

I'm working on a java project with spring on eclipse using Maven, and running on a Tomcat server v6.0. Everything was working fine since yesterday morning.
Here his my problem : I'm building my project, I got a build success. Then I start my Tomcat server and got this error :
org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: Failed to import bean definitions from URL location [classpath:applicationContext- core.xml]
Offending resource: ServletContext resource [/WEB-INF/applicationContext.xml]; nested exception is org.springframework.beans.factory.BeanDefinitionStoreException: IOException parsing XML document from class path resource [applicationContext-core.xml]; nested exception is java.io.FileNotFoundException: class path resource [applicationContext-core.xml] cannot be opened because it does not exist
I found out similar problem on some website but none of them give me a solution that worked for me.
It seems that eclipse isn't able to find applicationContext-core.xml when I'm doing this :
<import resource="classpath:applicationContext-core.xml" />
However, I do have the needed jar file nad-core-0.0.1-SNAPSHOT.jar in WEB-INF/lib containing applicationContext-core.xml.
I even tried to add it manually to the classpath but I was still having the same problem.
I keep on looking for a solution, when suddendly it work again once after restarting Eclipse and building while Eclipse was still updating indexes and my project was having this strange status Hg status pending instead of default. Surprised by this result I decide to build again my project after restarting Eclipse and I got the error again and I enable to make it work again. It's quite annoying...
This looks to be a really random problem.
Thanks a lot for your help :)

As you've not specified you web application structure. I assume you've a simple web application at hand with the following structures
webapp
WEB-INF/classes/applicationContext.xml
WEB-INF/lib/nad-core-0.0.1-SNAPSHOT.jar/applicationContext-core.xml
Application context.xml refers to the applicationContext-core.xml file using the import tag. I did encounter a similar situation in my web application, here're the check lists that you should go through and may be one of them can apply to your situation.
Check the generated snapshot jar file for the applicationContext-core.xml file and make sure it is in the root directory of the jar. As silly as it sounds, this was the root cause of the issue I faced in my deployment.
Make sure your Maven Pom.xml file is configured to include this XML file from the resources folder. You can use the resource tags in the build phase of Maven to package them within the jar file itself.
You can try removing the import tag from application context.xml file and instead load both of them from Spring's webapplication context itself.
Add a context loader listener class from spring org.springframework.web.context.ContextLoaderListener
Add context-param contextConfigLocation with value classpath:applicationContext-core.xml,classpath:applicationContext.xml. Spring has the ability to dynamically sort out the dependencies before initiating the bean factory.
Hope this check list helps.

I get pretty much the same config, six years later, I got the same error.
I also restart Eclipse, and it solved the issue.

How to load Spring context xml from a jar file

I am running a Junit (SpringJUnit4ClassRunner) to access some spring beans in my integration test.
I need to load a few xml files via #ContextConfiguration, those files are deployed by a external approach to my Tomcat directly via a jar file. -- In other words, these files are in:
my_tomcat_home_path/webapps//WEB-INF/lib/external.jar
such as
my_tomcat_home_path/webapps//WEB-INF/lib/external.jar/a.suffix.xml
my_tomcat_home_path/webapps//WEB-INF/lib/external.jar/b.suffix.xml
...
I put Tomcat path into my eclipse classpath, then if I also include the that into my eclipse classpath, then the following code in my JUnit works
#ContextConfiguration(locations = {"classpath:*suffix.xml"})
However, if I don't put that into my eclipse classpath (because the jar file name may change from time to time), then my following code does NOT work (but Tomcat home "" is still in eclipse classpath):
#ContextConfiguration(locations = {"classpath:/webapps/<my_app>/WEB-INF/lib/external.jar/*suffix.xml"})
Could somebody please help me out?
Thanks a lot!!
Additional try -------------------------------
I tried to use the package path inside the jar, instead of using the external.jar itself. The the code looks like the following:
#ContextConfiguration(locations = {"classpath:/webapps/<my_app>/WEB-INF/lib/path_inside_the_external_jar/*suffix.xml"})
In this case, I no longer get "XML not found because file does not exist" problem. Instead, I get the following errors:
Caused by: java.io.FileNotFoundException: class path resource [webapps/my_app/WEB-INF/lib/path_inside_the_external_jar/] cannot be resolved to URL because it does not exist
at org.springframework.core.io.ClassPathResource.getURL(ClassPathResource.java:163)
at org.springframework.core.io.support.PathMatchingResourcePatternResolver.isJarResource(PathMatchingResourcePatternResolver.java:406)
at org.springframework.core.io.support.PathMatchingResourcePatternResolver.findPathMatchingResources(PathMatchingResourcePatternResolver.java:338)
at org.springframework.core.io.support.PathMatchingResourcePatternResolver.getResources(PathMatchingResourcePatternResolver.java:276)
at org.springframework.context.support.AbstractApplicationContext.getResources(AbstractApplicationContext.java:1018)
at org.springframework.context.support.GenericApplicationContext.getResources(GenericApplicationContext.java:192)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:177)
... 23 more

Thanks a lot to Didxga's help!!
I tried to remove the "/webapps//WEB-INF/lib", and only leave the package path to the *suffix.xml (which are actually *.hbm.xml), then the #ContextConfiguration(locations looks like the following:
"classpath:/internal_path_within_jar/*hbm.xml"
at first, which is still not working.
Afterward, I tried the modify the classpath pattern and the following code ALMOST works
"classpath*:/internal_path_within_jar/*hbm.xml"
This time, since hbm.xml files are loaded, and I get the following error:
Caused by: java.net.UnknownHostException: hibernate.sourceforge.net
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:195)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
at java.net.Socket.connect(Socket.java:529)
at java.net.Socket.connect(Socket.java:478)
at sun.net.NetworkClient.doConnect(NetworkClient.java:163)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:411)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:525)
at sun.net.www.http.HttpClient.<init>(HttpClient.java:208)
at sun.net.www.http.HttpClient.New(HttpClient.java:291)
at sun.net.www.http.HttpClient.New(HttpClient.java:310)
However, I think now it is a different problem because it is hibernate DTD load problem... Maybe I should NOT load hbm.xml in this approach... I was forced to do so, because those hbm.xml files are generated during the deployment progress of my application and will only appear in the Tomcat's websapp/my_app/external.jar and NOwhere else...
Hmm, so I need work on that part... but how to include a jar into my eclipse path with changing name but a certain pattern? Such as *-dao.jar. OMG...
Anyway, I suppose the problem reported in this post should be resolved.
Thanks a lot, didxga!

GWT with JPA - no persistence provider

GWT with JPA
There are two projects in my eclipse workspace, let's name them:
-JPAProject
-GWTProject
JPAProject contains JPA configuration stuff (persistence.xml, entity classes and so on). GWTProject is an examplary GWT project (taken from official GWT tutorial).
Both projects work fine alone. That is, I can create EMF (EntityManagerFactory) in JPAProject and get entities from the database. GWTProject works fine too, I can run it, fill the field text in the browser and get the response.
My goal is to call JPAProject from GWTProject to get entities. But the problem is that when calling DAO, I get the following exception:
[WARN] Server class 'com.emergit.service.dao.profile.ProfileDaoService' could not be found in the web app, but was found on the system classpath
[WARN] Adding classpath entry 'file:/home/maliniak/workspace/emergit/build/classes/' to the web app classpath for this session
[WARN] /gwttest/greet
javax.persistence.PersistenceException: No Persistence provider for EntityManager named emergitPU
at javax.persistence.Persistence.createEntityManagerFactory(Unknown Source)
at javax.persistence.Persistence.createEntityManagerFactory(Unknown Source)
at com.emergit.service.dao.profile.JpaProfileDaoService.<init>(JpaProfileDaoService.java:19)
at pl.maliniak.server.GreetingServiceImpl.<init>(GreetingServiceImpl.java:21)
...
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:380)
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:395)
at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:488)
[ERROR] 500 - POST /gwttest/greet (127.0.0.1) 3812 bytes
I guess that the warnings at the beginning can be omitted for now.
Do you have any ideas? I guess I am missing some basic point. All hints are highly appreciated.
Update: My persistence provider is well defined, the JPA project works well by itself.
I guess it's classpath related problem too. When running the GWT project, in WEB-INF/lib there is only gwt-servlet.jar.
Do you think that making custom Ant file to build whole thing up is the only solution (i.e. make jar out of the JPA project and copying it to WEB-INF/lib)? Or is there any Eclipse solution, so I could set the GWT project properties properly so GWT project would know to include persistence.xml file?
Update: OK, I got it working. I tried to put persitence.xml everywhere in war/WEB-INF where it was possible, but kept getting 'no persistence provider' error. It turned out that it wasn't about persistence.xml. I didn't copy the eclipselink jar to WEB-INF/lib, so it couldn't find provider class defined in persistence.xml. Copying all the jars did the thing.
Thank you very much Pascal.

Struggling a lot with the same error message, I solved the problem with copying all jars (eclipselink.jar, eclipselink-jpa-modelgen_2.1.0.v20100614-r7608.jar, javax.persistence_1.0.0.jar, javax.persistence_2.0.1.v201006031150.jar) from the EclipseLink zip to the .../war/WEB-INF/lib folder of my GWT project to make everything available for the Jetty in hosted mode.
As you can see from the list of files, I was using EclipseLink 2.1. Please adapt this list to your JPA implementation, if necessary.
Hoping, that this may help you as well.

Do you have a persistence provider declared in your persistence.xml? Something like this (I'm using Hibernate here, adapt it to whatever persistence provider you're using):
<persistence
<persistence-unit name="emergitPU" transaction-type="...">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
...
</persistence-unit>
</persistence>
If you do, then I suspect a classpath problem. Did you package the JPA project correctly in the webapp i.e. in WEB-INF/lib?