TP.registerProbeHandler not thread safe --------------------------------------- Key: JGRP-1869 URL: https://issues.jboss.org/browse/JGRP-1869 Project: JGroups Issue Type: Bug Affects Versions: 3.2.12 Reporter: Dennis Reed Assignee: Bela Ban Priority: Minor Fix For: 3.5 TP.registerProbeHandlers is not thread safe since it modifies preregistered_probe_handlers outside of any synchronization. If a thread calls this method while another thread is inside startDiagnostics (which can happen easily with a shared transport), it can cause a NullPointerException when startDiagnostics is looping through preregistered_probe_handlers. Access to preregistered_probe_handlers should be synchronized.