Can't find a deployment unit in .war file. Persistence.xml issue.

[aarnold]

I am trying to use hibernate with mysql for data pesistence.  I am running JBoss AS7.  When the container goes to load my EntityManager, I get this error:  "java.lang.RuntimeException: Can't find a deployment unit named  at deployment "myProject.war"".

I looked extensively online for a solution.  Most problems seem to deal with .ear archives.  I am not packaging in an .ear, I am packaging is a .war.  In fact I am using the appraoch described in the jboss as7 quick start guide.  ( I am not using the ejb apprach). 

Here is my persistence.xml:

<?xml version="1.0" encoding="UTF-8"?>

<persistence xmlns="http://java.sun.com/xml/ns/persistence"

   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

   xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"

   version="2.0">

   <persistence-unit name="myDatabase">

      <provider>org.hibernate.ejb.HibernatePersistence</provider>

      <jta-data-source>java:jboss/datasources/MySqlDS</jta-data-source>

      <properties>

         <property name="hibernate.hbm2ddl.auto" value="create-drop" />

      </properties>

   </persistence-unit>

</persistence>

Here is my Resources.java (class producing the EntityManager):

package com.missionse.de.coda.data;

import java.util.logging.Logger;

import javax.enterprise.inject.Produces;

import javax.enterprise.inject.spi.InjectionPoint;

import javax.persistence.EntityManager;

import javax.persistence.PersistenceContext;

public class Resources {

   // Expose an entity manager using the resource producer pattern

   @SuppressWarnings("unused")

   @PersistenceContext(name = "myDatabase")

   @Produces

   private EntityManager em;

   @Produces

   Logger getLogger(InjectionPoint ip) {

      String category = ip.getMember().getDeclaringClass().getName();

      return Logger.getLogger(category);

   }

}

[aarnold]

continued....

Here is my interface:

package com.missionse.de.coda.data;

import java.util.List;

public interface DataManager {

   public String addData(Data data) throws Exception;

   public Data findData(String username) throws Exception;

}

Here is my implementation:

package com.missionse.de.coda.data;

import java.util.List;

import java.util.logging.Logger;

import javax.enterprise.context.RequestScoped;

import javax.inject.Inject;

import javax.inject.Named;

import javax.persistence.EntityManager;

import javax.transaction.UserTransaction;

@Named("dataManager")

@RequestScoped

public class ManagedBeanDataManager implements DataManager {

   @Inject

   private transient Logger logger;

   @Inject

   private EntityManager userDatabase;

   @Inject

   private UserTransaction utx;

   public String addData(Data data) throws Exception {

      try {

         try {

            utx.begin();

            userDatabase.persist(data);

            logger.info("Added " + data);

         } finally {

            utx.commit();

         }

      } catch (Exception e) {

         utx.rollback();

         throw e;

      }

      return "userAdded";

   }

   public Data findData(String name) throws Exception {

      try {

         try {

            utx.begin();

            @SuppressWarnings("unchecked")

            List<Data> results = userDatabase

                  .createQuery("select u from User u where u.username=:username and u.password=:password")

                  .setParameter("name",name).getResultList();

            if (results.isEmpty()) {

               return null;

            } else if (results.size() > 1) {

               throw new IllegalStateException("Cannot have more than one user with the same username!");

            } else {

               return results.get(0);

            }

         } finally {

            utx.commit();

         }

      } catch (Exception e) {

         utx.rollback();

         throw e;

      }

   }

}

When I try to use it like this I get the error....

...

@Inject

DataManager dm;

...

dm.addData(new Data());

[rnott]

Based on your error message, I'd guess the container is not finding your persistence.xml file. Here are the rules on where the container will search:  https://docs.jboss.org/author/display/AS7/JPA+Reference+Guide

Beware that the rule which states WEB-INF/classes will be searched appears to be false, at least in the version I'm using (7.1.0.Beta1b). In my case, I simply add a new JAR to WEB-INF/lib whose only contents are META-INF/persistence.xml and it's suddenly found.