code: @Test public void testInvokeGreaterActives(){
    URL url=URL.valueOf("test://test:11/test?accesslog=true&group=dubbo&version=1.1&actives=1&timeout=1");
    final Invoker<ActiveLimitFilterTest> invoker=new BlockMyInvoker<ActiveLimitFilterTest>(url,100);
    final Invocation invocation=new MockInvocation();
    final CountDownLatch latch=new CountDownLatch(1);
    for (int i=0; i < 100; i++) {
      Thread thread=new Thread(new Runnable(){
        public void run(){
          try {
            latch.await();
          }
   catch (        InterruptedException e) {
            e.printStackTrace();
          }
          for (int i=0; i < 100; i++) {
            try {
              activeLimitFilter.invoke(invoker,invocation);
            }
   catch (          RpcException expected) {
              count++;
            }
          }
        }
      }
  );
      thread.start();
    }
    latch.countDown();
    try {
      Thread.sleep(1000);
    }
   catch (  InterruptedException e) {
      e.printStackTrace();
    }
    assertNotSame(0,count);
  }
  