org.postgresql.util.PSQLException: This connection has been closed.
   at org.postgresql.jdbc2.AbstractJdbc2Connection.checkClosed(AbstractJdbc2Connection.java:822)
   at org.postgresql.jdbc2.AbstractJdbc2Connection.getCatalog(AbstractJdbc2Connection.java:986)
   at org.netbeans.modules.dbschema.jdbcimpl.DDLBridge.<init>(DDLBridge.java:70)
   at org.netbeans.modules.dbschema.jdbcimpl.SchemaElementImpl.initTables(SchemaElementImpl.java:250)
   at org.netbeans.modules.dbschema.jdbcimpl.SchemaElementImpl.initTables(SchemaElementImpl.java:228)
   at org.netbeans.modules.j2ee.persistence.wizard.fromdb.DBSchemaManager$3.run(DBSchemaManager.java:207)
   at org.netbeans.modules.j2ee.core.api.support.progress.ProgressSupport$ActionInvoker.invokeNextActionsOfSameKind(ProgressSupport.java:270)
   at org.netbeans.modules.j2ee.core.api.support.progress.ProgressSupport$ActionInvoker.access$100(ProgressSupport.java:118)
   at org.netbeans.modules.j2ee.core.api.support.progress.ProgressSupport$ActionInvoker$1.run(ProgressSupport.java:159)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1423)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2033)