I'm trying out embeddable JBoss with the EJBContainer.createEJBContainer API described in the spec (JSR 318: Enterprise JavaBeans, Version 3.1, ch. 22: Embeddable Usage), not any of the various predecessors using JBoss specific APIs.
Overview
- When i invoke my main method normally, a session bean invocation succeeds. But there seem to be some classloading issues, because the JNDI object at
"java:jboss/UserTransaction"cannot be cast to javax.transaction.UserTransaction. - So i guess the classloading magic of JBoss Modules is required here. With my attempts at that, createEJBContainer does not find any EJBContainerProviders and throws an EJBException.
Note that not all my questions require reading all subsequent details. So if this is too much to read, please have a look at the questions section nevertheless. Thanks!
Environment
JBoss AS 7.1.1.Final (jboss-as-7.1.1.Final.zip with only logging conf changed in standalone.xml)
(Initially JBoss EAP 6.0.1 GA which is the actual target environment - same problem)
Oracle JDK 1.7.0_11
Windows 7 Prof 64 bit
Details
The stateless session bean
package test.helloworld.impl;
import javax.ejb.Remote;
import javax.ejb.Stateless;
import test.helloworld.api.HelloWorld;
@Stateless
@Remote(HelloWorld.class)
public class HelloWorldBean implements HelloWorld
{
@Override
public String salute()
{
return "Hello, world";
}
}
... and its business interface:
package test.helloworld.api;
public interface HelloWorld
{
String salute();
}
The client program
package test.helloworld.client;
import static java.lang.System.out;
import java.io.File;
import java.util.HashMap;
import java.util.Map;
import javax.ejb.embeddable.EJBContainer;
import javax.naming.Context;
import javax.transaction.UserTransaction;
import test.helloworld.api.HelloWorld;
public class HelloWorldEmbeddedEjbTestClient
{
public static void main(String[] args)
{
int status = 1;
try
{
main();
status = 0;
}
catch (Throwable e)
{
e.printStackTrace(System.err);
System.err.flush();
}
finally
{
// Simply returning from main leaves some thread (and
// hence the JVM) running for another 60s, so force exit
System.exit(status);
}
}
private static void main() throws Exception
{
Map<String, Object> properties = new HashMap<String, Object>();
properties.put(EJBContainer.MODULES, new File[]{new File("./HelloWorld-EJB.jar")});
EJBContainer container = EJBContainer.createEJBContainer(properties);
try
{
Context jndiContext = container.getContext();
Object serviceObj = jndiContext.lookup("java:global/HelloWorld-EJB/HelloWorldBean");
out.println("service:\t" + serviceObj);
HelloWorld service = (HelloWorld) serviceObj;
out.println("result:\t" + service.salute());
callInTx(service, jndiContext);
}
finally
{
out.println("closing EJBContainer...");
container.close();
out.println("EJBContainer closed.");
}
}
private static void callInTx(HelloWorld service, Context jndiContext) throws Exception
{
UserTransaction tx = (UserTransaction) jndiContext.lookup("java:jboss/UserTransaction");
tx.begin();
out.println("result in tx:\t" + service.salute());
tx.commit();
}
}
Packaging
C:\eclipse\projects\HelloWorldSlSB-Client\rt\HelloWorld-API.jar:
META-INF/MANIFEST.MF
test/helloworld/api/HelloWorld.class
C:\eclipse\projects\HelloWorldSlSB-Client\rt\HelloWorld-EJB.jar:
META-INF/MANIFEST.MF
META-INF/jboss-deployment-structure.xml
test/helloworld/impl/HelloWorldBean.class
test/helloworld/api/HelloWorld.class
HelloWorld-EJB.jar:META-INF/jboss-deployment-structure.xml:
<?xml version="1.0" encoding="ISO-8859-1"?>
<jboss-deployment-structure>
<deployment>
<dependencies></dependencies>
<exclusions>
<module name="Classpath"/>
</exclusions>
</deployment>
</jboss-deployment-structure>
C:\eclipse\projects\HelloWorldSlSB-Client\rt\modules\test\helloworld\client\main\HelloWorldSlSB-Client.jar:
META-INF/MANIFEST.MF
test/helloworld/client/HelloWorldEmbeddedEjbTestClient.class
C:\eclipse\projects\HelloWorldSlSB-Client\rt\modules\test\helloworld\client\main\module.xml:
<main-class name="test.helloworld.client.HelloWorldEmbeddedEjbTestClient"/>
<resources>
<resource-root path="HelloWorldSlSB-Client.jar"/>
</resources>
<dependencies>
<module name="javax.api"/>
<module name="javax.ejb.api"/>
<module name="org.jboss.as.embedded" export="true"/>
<!--
<module name="org.jboss.as.server" export="true"/>
-->
</dependencies>
</module>
All META-INF/MANIFEST.MF files contain nothing but "Manifest-Version: 1.0".
Results
Direct invocation
With a direct invocation of HelloWorldEmbeddedEjbTestClient.main with -Xmx512m -XX:MaxPermSize=256m, classpath
C:\eclipse\output\HelloWorldSlSB-Client
C:\java\jboss-as-7\jboss-modules.jar
C:\java\jboss-as-7\modules\org\jboss\as\embedded\main\jboss-as-embedded-7.1.1.Final.jar
C:\java\jboss-as-7\modules\javax\ejb\api\main\jboss-ejb-api_3.1_spec-1.0.1.Final.jar
C:\java\jboss-as-7\modules\javax\transaction\api\main\jboss-transaction-api_1.1_spec-1.0.0.Final.jar
C:\java\jboss-as-7\modules\org\jboss\logging\main\jboss-logging-3.1.0.GA.jar
C:\java\jboss-as-7\modules\org\jboss\as\controller-client\main\jboss-as-controller-client-7.1.1.Final.jar
C:\java\jboss-as-7\modules\org\jboss\logmanager\main\jboss-logmanager-1.2.2.GA.jar
C:\java\jboss-as-7\modules\org\jboss\dmr\main\jboss-dmr-1.1.1.Final.jar
C:\eclipse\projects\HelloWorldSlSB-Client\rt\HelloWorld-API.jar
and system properties
-Duser.language=en
-Djboss.home=c:/java/jboss-as-7
-Djboss.home.dir=c:/java/jboss-as-7
-Dorg.jboss.as.embedded.ejb3.BARREN=true
-Dfile.encoding=ISO-8859-1
the EJB invocation succeeds, but JNDI object "java:jboss/UserTransaction" cannot be cast to javax.transaction.UserTransaction:
...
19:21:01,875 INFO [org.jboss.ejb.client] (main) JBoss EJB Client version 1.0.5.Final
service: Proxy for remote EJB StatelessEJBLocator{appName='', moduleName='HelloWorld-EJB', distinctName='', beanName='HelloWorldBean', view='interface test.helloworld.api.HelloWorld'}
result: Hello, world
closing EJBContainer...
19:21:06,362 INFO [org.jboss.as.server.deployment] (MSC service thread 1-7) JBAS015877: Stopped deployment HelloWorld-EJB.jar in 90ms
19:21:06,370 INFO [org.jboss.as.repository] (pool-9-thread-1) JBAS014901: Content removed from location c:\java\jboss-as-7\standalone\data\content\35\424415b9a67d64fe8a6dc7ee0700480282f34b\content
19:21:06,370 INFO [org.jboss.as.server] (pool-9-thread-1) JBAS018558: Undeployed "HelloWorld-EJB.jar"
19:21:06,390 INFO [org.jboss.as.osgi] (MSC service thread 1-1) JBAS011942: Stopping OSGi Framework
EJBContainer closed.
java.lang.ClassCastException: org.jboss.tm.usertx.client.ServerVMClientUserTransaction cannot be cast to javax.transaction.UserTransaction
at test.helloworld.client.HelloWorldEmbeddedEjbTestClient.callInTx(HelloWorldEmbeddedEjbTestClient.java:65)
at test.helloworld.client.HelloWorldEmbeddedEjbTestClient.main(HelloWorldEmbeddedEjbTestClient.java:52)
at test.helloworld.client.HelloWorldEmbeddedEjbTestClient.main(HelloWorldEmbeddedEjbTestClient.java:21)
(Looks a little strange, because the exception is caught and printed at the end of main. But of course, it happens before the container is closed.)
The debugger shows that the JNDI object's getClass().getClassLoader() is org.jboss.modules.ModuleClassLoader
ModuleClassLoader for Module "org.jboss.jboss-transaction-spi:main" from local module loader @4b436982 (roots: c:\java\jboss-as-7\modules)
and its getClass().getInterfaces()[0] /* == interface javax.transaction.UserTransaction */.getClassLoader() is
ModuleClassLoader for Module "javax.transaction.api:main" from local module loader @4b436982 (roots: c:\java\jboss-as-7\modules)
However, UserTransaction.class.getClassLoader() is of type sun.misc.Launcher$AppClassLoader.
jboss-modules.jar invocation
Invoked via org.jboss.modules.Main.main (i.e. what java -jar jboss-modules.jar also does) with classpath
C:\java\jboss-as-7\jboss-modules.jar
system properties as above, and arguments
-mp "C:\java\jboss-as-7\modules;C:\eclipse\projects\HelloWorldSlSB-Client\rt\modules"
test.helloworld.client
it fails already in createEJBContainer:
javax.ejb.EJBException: Unable to instantiate container with factories []
at javax.ejb.embeddable.EJBContainer.createEJBContainer(EJBContainer.java:97)
at test.helloworld.client.HelloWorldEmbeddedEjbTestClient.main(HelloWorldEmbeddedEjbTestClient.java:42)
at test.helloworld.client.HelloWorldEmbeddedEjbTestClient.main(HelloWorldEmbeddedEjbTestClient.java:21)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.jboss.modules.Module.run(Module.java:260)
at org.jboss.modules.Main.main(Main.java:291)
Debugging shows that this happens because in method EJBContainer.findAllFactories(), no resources "META-INF/services/javax.ejb.spi.EJBContainerProvider" are found in the thread context classloader, which is
ModuleClassLoader for Module "test.helloworld.client:main" from local module loader @1afec586 (roots: C:\java\jboss-as-7\modules,C:\eclipse\projects\HelloWorldSlSB-Client\rt\modules)
Questions
- Does anyone know how to fix this or has gotten anything similar to work?
- Is a normal JBoss installation the right starting point, or do i need a specific embeddable variant?
- Is UserTransaction even supposed to be usable in the embeddable scenario?
- If it is, does that mean i could also use one XA datasource for both JPA 2 CMT entities and legacy JDBC code? And both could participate in the same transaction (e.g. JDBC code starts tx with java.sql.Connection.setAutoCommit(false), then calls EJB with TransactionAttributeType.REQUIRED)?
- Can someone point me to some documentation? All i find is about the older stuff with JBoss specific API, not the standard EJB 3.1 way.
- Preferably, documentation how to use without any test frameworks, since i'm evaluating this for production use.
Thanks for reading all (or part of :-) this!
