Programmatic deadlock detection in java

java multithreading concurrency deadlock
Raji picture Raji · Jul 9, 2009 · Viewed 37.1k times · Source

How can I programmatically detect that a deadlock has occurred in a Java program?

Answer

Adamski picture Adamski · Jul 9, 2009

You can do this programmatically using the ThreadMXBean that ships with the JDK:

ThreadMXBean bean = ManagementFactory.getThreadMXBean();
long[] threadIds = bean.findDeadlockedThreads(); // Returns null if no threads are deadlocked.

if (threadIds != null) {
    ThreadInfo[] infos = bean.getThreadInfo(threadIds);

    for (ThreadInfo info : infos) {
        StackTraceElement[] stack = info.getStackTrace();
        // Log or store stack trace information.
    }
}

Obviously you should try to isolate whichever thread is performing this deadlock check - Otherwise if that thread deadlocks it won't be able to run the check!

Incidentally this is what JConsole is using under the covers.

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