public List<String> getChildren(final String key) {
        try {
            return client.getChildren().forPath(key);
        } catch (Exception e) {
            throw new ShenyuException(e);
        }
    }
get children with specific key.

@param key zookeeper key.
@return children node name.
shenyu-registry/shenyu-registry-zookeeper/src/main/java/org/apache/shenyu/registry/zookeeper/ZookeeperClient.java