[esb-issues] [JBoss JIRA] (JBESB-3853) NPE thrown in SqlTableGatewayListener.getDbConn() causes the listener to stop polling

[ https://issues.jboss.org/browse/JBESB-3853?page=com.atlassian.jira.plugin... ] Tadayoshi Sato commented on JBESB-3853: --------------------------------------- In the source code of JBoss ESB 4.10, the following object {{"oConn"}} can be null and subsequently a NPE can happen because after the first successful invocation of {{getDbConn()}} the datasource gets out of service. {code} 473 final JdbcCleanConn oConn = getDbConn(); {code} After the initial run of {{getDbConn()}} the {{JdbcCleanConn}} object is cached to_the {{dbConn}} field, so the following if block won't be executed subsequently. {code} 544 protected JdbcCleanConn getDbConn() { 545 DataSource oDS = null; 546 if (null == _dbConn) { ... 566 _dbConn = new JdbcCleanConn(oDS, transacted); 567 } {code} And rushing directly into the following line with shortage of the datasource will raise a {{SQLException}} and execute {{releaseDBConnection()}} in the catch block, where is exactly the place of resetting the {{dbConn}} field to null. {code} 569 if ((null != _dbConn) && (_dbConn.getStatements().size() == 0)) { 570 try { 571 prepareStatements(); 572 } catch (SQLException e) { 573 releaseDBConnection(); 574 _ logger.warn("Exception preparing statements", e); 575 } 576 } {code} That's why we will have a NPE at the following line 509 and eventually {{SqlTableGatewayListener}} will stop. {code} 471 protected List<Map<String, Object>> pollForCandidates() { ... 473 final JdbcCleanConn oConn = getDbConn(); ... 509 oConn.rollback(); {code} So, I'd say the {{SqlTableGatewayListener}} can terminate forever regardless of the datasource being recovered later in such a scenario that the datasource becomes unavailable temporarily and have failed to make prepared statements by chance. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira