public void waitUntilConnected() throws ZkInterruptedException {
        waitUntilConnected(Integer.MAX_VALUE, TimeUnit.MILLISECONDS);
    }
Counts number of children for the given path.

@param path
@return number of children or 0 if path does not exist.
shared/common/src/main/java/com/alibaba/otter/shared/common/utils/zookeeper/ZkClientx.java