int delayGetSize(final AddressHolder addressHolder, int expect, int n50ms) {
        return TestUtils.delayGet(new Callable<Integer>() {
            @Override
            public Integer call() throws Exception {
                return addressHolder.getAllProviderSize();
            }
        }, expect, 70, n50ms);
    }
@author <a href="mailto:zhanggeng.zg@antfin.com">GengZhang</a>
test/test-integration-3rd/src/test/java/com/alipay/sofa/rpc/registry/zk/ZookeeperOverrideObserverTest.java