[jboss-jira] [JBoss JIRA] Closed: (JBAS-5904) ClientUserTransaction singleton initialisation is not thread safe

ClientUserTransaction singleton initialisation is not thread safe ----------------------------------------------------------------- Key: JBAS-5904 URL: https://jira.jboss.org/jira/browse/JBAS-5904 Project: JBoss Application Server Issue Type: Bug Security Level: Public(Everyone can see) Components: Transaction Manager (JBossTM) Affects Versions: JBossAS-5.0.0.CR1, JBossAS-4.2.3.GA Reporter: Adrian Brock Assignee: Adrian Brock Fix For: JBossAS-5.0.0.CR2, JBossAS-4.2.4.GA The ClientUserTransaction singleton initialistation is not thread safe: private static ClientUserTransaction singleton = null; public static ClientUserTransaction getSingleton() { if (singleton == null) singleton = new ClientUserTransaction(); return singleton; } Two threads can race to create the singleton which means the ThreadLocal within the class can become "masked". The construction of the singleton needs moving to static initialisation.