zk java api

1.pom 文件

        
            org.apache.zookeeper
            zookeeper
            3.4.8
        
        
            org.apache.curator
            curator-framework
            4.0.0
        
        
            org.apache.curator
            curator-recipes
            4.0.0
        

2.zk 操作

package com.vince.xq.kafka;

import org.apache.curator.framework.Curatorframework;
import org.apache.curator.framework.CuratorframeworkFactory;
import org.apache.curator.retry.ExponentialBackoffRetry;
import org.apache.zookeeper.*;
import org.apache.zookeeper.data.Stat;
import org.junit.Test;

import java.util.concurrent.CountDownLatch;

public class ZKTest {
    @Test
    public void testZkConnect() throws Exception {
        final CountDownLatch countDownLatch = new CountDownLatch(1);
        ZooKeeper zooKeeper =
                new ZooKeeper("127.0.0.1:2181",
                        4000, new Watcher() {
                    @Override
                    public void process(WatchedEvent event) {
                        if (Event.KeeperState.SyncConnected == event.getState()) {
                            //如果收到了服务端的响应事件，连接成功
                            countDownLatch.countDown();
                        }
                    }
                });
        countDownLatch.await();
        //ConNECTED
        //zooKeeper.create("/CONFIG/timeout", "0".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
        zooKeeper.delete("/CONFIG/timeout", -1);
        System.out.println(zooKeeper.getState());
    }

    @Test
    public void testZkCreateNode() throws Exception {
        final CountDownLatch countDownLatch = new CountDownLatch(1);
        ZooKeeper zooKeeper =
                new ZooKeeper("127.0.0.1:2181",
                        4000, new Watcher() {
                    @Override
                    public void process(WatchedEvent event) {
                        if (Event.KeeperState.SyncConnected == event.getState()) {
                            //如果收到了服务端的响应事件，连接成功
                            countDownLatch.countDown();
                        }
                    }
                });
        countDownLatch.await();
        //ConNECTED
        String path = "/watcher";
        String nodePath = zooKeeper.create(path, "123".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
        System.out.println(nodePath);
        System.out.println(zooKeeper.getState());
    }

    @Test
    public void testZkDeleteNode() throws Exception {
        final CountDownLatch countDownLatch = new CountDownLatch(1);
        ZooKeeper zooKeeper =
                new ZooKeeper("127.0.0.1:2181",
                        4000, new Watcher() {
                    @Override
                    public void process(WatchedEvent event) {
                        if (Event.KeeperState.SyncConnected == event.getState()) {
                            //如果收到了服务端的响应事件，连接成功
                            countDownLatch.countDown();
                        }
                    }
                });
        countDownLatch.await();
        //ConNECTED
        zooKeeper.delete("/watcher", -1);
        System.out.println(zooKeeper.getState());
    }


    @Test
    public void getZkNodeData() throws Exception {
        final CountDownLatch countDownLatch = new CountDownLatch(1);
        ZooKeeper zooKeeper =
                new ZooKeeper("127.0.0.1:2181",
                        4000, new Watcher() {
                    @Override
                    public void process(WatchedEvent event) {
                        if (Event.KeeperState.SyncConnected == event.getState()) {
                            //如果收到了服务端的响应事件，连接成功
                            countDownLatch.countDown();
                        }
                    }
                });
        countDownLatch.await();

        Stat stat = new Stat();
        // getData的返回值是该节点的数据值，节点的状态信息会赋值给stat对象
        byte[] data = zooKeeper.getData("/CONFIG/timeout", true, stat);
        System.out.println(new String(data));
        System.out.println(stat);
        System.out.println(zooKeeper.getState());
    }


    @Test
    public void getZkConnect() throws Exception {
        Curatorframework curatorframework = CuratorframeworkFactory.
                builder().connectString("127.0.0.1:2181").
                sessionTimeoutMs(4000).retryPolicy(new
                ExponentialBackoffRetry(1000, 3)).
                namespace("").build();
        curatorframework.start();
        Stat stat = new Stat();
        //查询节点数据
        byte[] bytes = curatorframework.getData().storingStatIn(stat).forPath("/runoob");
        System.out.println(new String(bytes));
        curatorframework.close();
    }

    @Test
    public void setData() throws Exception {
        Curatorframework curatorframework = CuratorframeworkFactory.
                builder().connectString("127.0.0.1:2181").
                sessionTimeoutMs(4000).retryPolicy(new
                ExponentialBackoffRetry(1000, 3)).
                namespace("").build();
        curatorframework.start();
        Stat stat = new Stat();
        //查询节点数据
        curatorframework.setData().forPath("/watcher", "123".getBytes());

        curatorframework.close();
    }

}

参考：

https://segmentfault.com/a/1190000012262940