Thread management in a Web application is forbidden in some circumstances and is always highly error prone.
Extended description
Thread management in a web application is forbidden by the J2EE standard in some circumstances and is always highly error prone. Managing threads is difficult and is likely to interfere in unpredictable ways with the behavior of the application container. Even without interfering with the container, thread management usually leads to bugs that are hard to detect and diagnose like deadlock, race conditions, and other synchronization errors.
Best practices to prevent this CWE
Phase: Architecture and Design
For EJB, use framework approaches for parallel execution, instead of using threads.