title: Hibernate throwing NullPointerException
body: <p>I'm trying to test Hibernate 4.2.1.Final with JPA using IntelliJ 12.1.3 and I am getting the following error. </p>
  
  <p>Everything seems to be setup OK (I let IntelliJ generate the mappings), and as I have zero experience with Hibernate and JPA I am at a loss as to why this is occurring.</p>
  
  <p><strong>Why am I getting an NPE on <code>EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory("Heroku-production");</code>?</strong></p>
  
  <p>main class:</p>
  
  <pre><code>public static void main(final String[] args) throws Exception {
          EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory("Heroku-production");
          EntityManager entityManager = entityManagerFactory.createEntityManager();
          entityManager.getTransaction().begin();
          List&lt;CountryCodesEntity&gt; result = entityManager.createQuery( "from CountryCodesEntity", CountryCodesEntity.class ).getResultList();
          for ( CountryCodesEntity countryCodesEntity : result ) {
              System.out.println( "Code (" + countryCodesEntity.getCode() + ") : " + countryCodesEntity.getNsenum() );
          }
          entityManager.getTransaction().commit();
          entityManager.close();
      }
  </code></pre>
  
  <p>Error:  </p>
  
  <pre><code>May 16, 2013 3:02:49 PM org.hibernate.annotations.common.Version &lt;clinit&gt;
  INFO: HCANN000001: Hibernate Commons Annotations {4.0.1.Final}
  May 16, 2013 3:02:49 PM org.hibernate.Version logVersion
  INFO: HHH000412: Hibernate Core {4.2.1.Final}
  May 16, 2013 3:02:49 PM org.hibernate.cfg.Environment &lt;clinit&gt;
  INFO: HHH000206: hibernate.properties not found
  May 16, 2013 3:02:49 PM org.hibernate.cfg.Environment buildBytecodeProvider
  INFO: HHH000021: Bytecode provider name : javassist
  May 16, 2013 3:02:54 PM org.hibernate.cfg.Configuration addResource
  INFO: HHH000221: Reading mappings from resource: com/***/heroku/CountryCodesEntity.xml
  May 16, 2013 3:02:54 PM org.hibernate.cfg.Configuration addResource
  INFO: HHH000221: Reading mappings from resource: com/***/heroku/StateCodesEntity.xml
  May 16, 2013 3:02:54 PM org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
  INFO: HHH000402: Using Hibernate built-in connection pool (not for production use!)
  May 16, 2013 3:02:54 PM org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
  INFO: HHH000115: Hibernate connection pool size: 20
  May 16, 2013 3:02:54 PM org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
  INFO: HHH000006: Autocommit mode: true
  May 16, 2013 3:02:54 PM org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
  INFO: HHH000401: using driver [org.postgresql.Driver] at URL [postgres://*********:***********@ec2-***-**-**-*****.compute-1.amazonaws.com:6232/******]
  May 16, 2013 3:02:54 PM org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
  INFO: HHH000046: Connection properties: {user=********, password=****, autocommit=true, release_mode=auto}
  Exception in thread "main" java.lang.NullPointerException
      at org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl.getConnection(DriverManagerConnectionProviderImpl.java:214)
      at org.hibernate.engine.jdbc.internal.JdbcServicesImpl$ConnectionProviderJdbcConnectionAccess.obtainConnection(JdbcServicesImpl.java:242)
      at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:117)
      at org.hibernate.service.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:75)
      at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:159)
      at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:131)
      at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:78)
      at org.hibernate.cfg.Configuration.buildSettingsInternal(Configuration.java:2293)
      at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2289)
      at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1758)
      at org.hibernate.ejb.EntityManagerFactoryImpl.&lt;init&gt;(EntityManagerFactoryImpl.java:96)
      at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:913)
      at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:898)
      at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:59)
      at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:63)
      at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:47)
      at Main.main(Main.java:20)
  </code></pre>
  
  <p>Persistance.xml</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  </code></pre>
  
  <p></p>
  
  <pre><code>&lt;persistence-unit name="Heroku-production"&gt;
      &lt;provider&gt;org.hibernate.ejb.HibernatePersistence&lt;/provider&gt;
      &lt;mapping-file&gt;com/***/heroku/CountryCodesEntity.xml&lt;/mapping-file&gt;
      &lt;mapping-file&gt;com/***/heroku/StateCodesEntity.xml&lt;/mapping-file&gt;
      &lt;properties&gt;
          &lt;property name="hibernate.connection.url" value="postgres://****:****@ec2-***-**-***-***.compute-1.amazonaws.com:6232/*****"/&gt;
          &lt;property name="hibernate.connection.driver_class" value="org.postgresql.Driver"/&gt;
          &lt;property name="hibernate.connection.username" value="****"/&gt;
          &lt;property name="hibernate.connection.password" value="****"/&gt;
          &lt;property name="hibernate.archive.autodetection" value="class"/&gt;
          &lt;property name="hibernate.show_sql" value="true"/&gt;
          &lt;property name="hibernate.format_sql" value="true"/&gt;
          &lt;property name="hbm2ddl.auto" value="update"/&gt;
      &lt;/properties&gt;
  &lt;/persistence-unit&gt;
  </code></pre>
  
  <p></p>