/** * This method is called by the system to give a Thread * a chance to clean up before it actually exits. */ private void exit() { if (group != null) { group.threadTerminated(this); group = null; } /* Aggressively null out all reference fields: see bug 4006245 */ target = null; /* Speed the release of some of these resources */ threadLocals = null; inheritableThreadLocals = null; inheritedAccessControlContext = null; blocker = null; uncaughtExceptionHandler = null; }以上就是Thread类中的exit方法,求解答!!!