@Override
  public void customize(Session session) throws Exception {
    // ensure db behavior is same as shared cache
    DatabaseLogin databaseLogin = (DatabaseLogin) session.getDatasourceLogin();
    databaseLogin.setTransactionIsolation(DatabaseLogin.TRANSACTION_READ_COMMITTED);

    // read-all queries use a Vector as their container for
    // result items - this seems like an unnecessary performance hit since
    // Vectors are synchronized and there's no apparent reason to provide a
    // thread-safe collection on a read all query
    // see: https://bugs.eclipse.org/bugs/show_bug.cgi?id=255634
    Object ddlGeneration = session.getProperty(PersistenceUnitProperties.DDL_GENERATION);
    if (null == ddlGeneration || PersistenceUnitProperties.NONE.equals(ddlGeneration)) {
      // only set this when not using DDL generation - Sequence generation hard
      // codes Vector
      ContainerPolicy.setDefaultContainerClass(ArrayList.class);
    }
  }
{@inheritDoc}
<p/>
This class exists for quick customization purposes.
ambari-server/src/main/java/org/apache/ambari/server/orm/EclipseLinkSessionCustomizer.java