How can I know the lock information in java?

Question

Is there any tool or way that can get all the information about the locks in java?

for example, if there is a java program, it creates two threads, and both threads require locks for some variable. Is there any tools that can output the information like which thread locks which variable?

Answer 1

You can use ThreadInfo#getLockedSynchronizers() ( JavaDoc ) via ThreadMXBean to get array of LockInfo on currently owned locks on threads. LockInfo will tell you just class name & identity hashcode of a lock, but that's sufficient in tracing lock objects.