481         destroy(true);

   481         destroy(true);

   482         return this;

   482         return this;

   483     }

   483     }

   484 

   484 

   485     @Override

   485     @Override

   486     public synchronized boolean isAlive() {

   491     public synchronized boolean isAlive() {

   487         return !hasExited;

   492         return !hasExited;

   488     }

   493     }

   489 

   494 

   490     private static native void init();

   495     private static native void init();