[jbpm-issues] [JBoss JIRA] Resolved: (JBPM-1766) Node.java getLeavingTransitionsMap() not thread safe when constructing leavingTransitionMap

Node.java getLeavingTransitionsMap() not thread safe when constructing leavingTransitionMap ------------------------------------------------------------------------------------------- Key: JBPM-1766 URL: https://jira.jboss.org/jira/browse/JBPM-1766 Project: JBoss jBPM Issue Type: Bug Security Level: Public(Everyone can see) Components: Core Engine Affects Versions: jBPM 3.3.0 CR1 Environment: N/A Reporter: joe freeman Priority: Critical The code in getLeavingTransitionsMap() lazily constructs the map the first time the method is called. Our application can have 100s of users going through the same node at the start of their shift. It is possible to have more than one user leaving the first node at the same time in the same VM. This can put multiple users in the getLeavingTransitionsMap() method at the same time. We can get deadlock in the put() method for the map which means no one else can enter the application. The block of code should be synchronized or the map should be synchronized. A simpler fix is to just remove the map. The number of transitions exiting a node is unlikely to ever be large enough to justify the complexity of two data structures pointing at the same objects. Iterating across the list is almost always going to be close enough in performance to remove the need for this map. We're running just the jpdl which has this problem up through and including the current 3.2.3 version /** * are the leaving {@link Transition}s, mapped by their name (java.lang.String). */ public Map getLeavingTransitionsMap() { if ( (leavingTransitionMap==null) && (leavingTransitions!=null) ){ // initialize the cached leaving transition map leavingTransitionMap = new HashMap(); ListIterator iter = leavingTransitions.listIterator(leavingTransitions.size()); while (iter.hasPrevious()) { Transition leavingTransition = (Transition) iter.previous(); leavingTransitionMap.put(leavingTransition.getName(), leavingTransition); } } return leavingTransitionMap; }