public void thread1() {
   try {
     assertFalse(l.isSignalled());
     l.acquireSharedInterruptibly(0);
     fail("should throw exception");
   } catch (InterruptedException success) {
     assertTick(1);
   }
 }
 public void thread1() throws InterruptedException {
   assertFalse(l.isSignalled());
   l.acquireSharedInterruptibly(0);
   assertTick(1);
   assertTrue(l.isSignalled());
 }