The Thread class provides some support for debugging, by way of its dumpStack() and toString() methods. When called, the dumpStack() method prints a stack trace of the current thread. (If you examine the source code for that method, you will discover new Exception ("Stack trace").printStackTrace ().) The toString() method, when called, returns a string representation of the current Thread object. That representation is in the form Thread[thread-name,priority,thread-group].