code: @Test(expected=RuntimeException.class) public void testSyncCallbackHasException() throws RpcException, Throwable {
    @SuppressWarnings("unchecked") Invoker<DemoService> invoker=mock(Invoker.class);
    given(invoker.isAvailable()).willReturn(true);
    given(invoker.getInterface()).willReturn(DemoService.class);
    RpcResult result=new RpcResult();
    result.setException(new RuntimeException());
    given(invoker.invoke(invocation)).willReturn(result);
    URL url=URL.valueOf("test://test:11/test?group=dubbo&version=1.1&" + Constants.ON_THROW_METHOD_KEY + "=echo");
    given(invoker.getUrl()).willReturn(url);
    eventFilter.invoke(invoker,invocation).recreate();
  }
  