Zookeeper入门看这篇就够了（3）

import lombok.extern.slf4j.Slf4j;
import org.apache.zookeeper.*;
import org.apache.zookeeper.data.Stat;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.concurrent.CountDownLatch;
/** @Author mxn
  * @Description //TODO ZooKeeper Java API测试
  * @Date 10:22 2021/9/29
  * @Param
  * @return
 **/
@Slf4j
public class ZookeeperTest {
    // IP 和端口
    private final static String ipAddress = "192.168.2.123:2181";
    public static void main(String[] args) {
        ZookeeperTest test = new ZookeeperTest();
        String key = "/zkMxn";
        String value = "wo is muxiaonong";
        //创建Znode
        test.add(key,value);
//        获取节点数据
//        test.get(key);
        //修改节点数据
//        test.modify(key,"wo is zhuzhuxia");
        //删除节点
//        test.delete(key);
    }
    /**
     * @return
     * @Author mxn
     * @Description //TODO 获取ZooKeeper连接
     * @Date 10:22 2021/9/29
     * @Param
     **/
    public static ZooKeeper getConntection() {
        ZooKeeper zooKeeper = null;
        try {
            final CountDownLatch countDownLatch = new CountDownLatch(1);
            //watch机制(回调)，监听是否连接成功
            zooKeeper = new ZooKeeper(ipAddress, 5000, new Watcher() {
                @Override
                public void process(WatchedEvent watchedEvent) {
                    if (Event.KeeperState.SyncConnected == watchedEvent.getState()) {
                        //如果受收到了服务端的响应事件，连接成功
                        countDownLatch.countDown();
                    }
                }
            });
            countDownLatch.await();
            log.info("zookeeper状态：{}",zooKeeper.getState());//CONNECTED
        } catch (IOException e) {
            e.printStackTrace();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        return zooKeeper;
    }
   /** @Author lyy
     * @Description //TODO 关闭ZooKeeper连接
     * @Date 14:57 2021/9/29
     * @Param 
     * @return 
    **/
    public static void closeConnection(ZooKeeper zooKeeper) {
        try {
//            zooKeeper.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    /** @Author lyy
      * @Description //TODO 添加节点
      * @Date 13:36 2021/9/29
      * @Param 
      * @return 
     **/
    public void add(String key ,String value) {
        ZooKeeper zooKeeper = ZookeeperTest.getConntection();
        try {
            //参数类型
            //1.key
            //2.value
            //3.对应的ACL,当前节点的权限控制
            //4.设置当前节点类型
            zooKeeper.create(key, value.getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
            ZookeeperTest.closeConnection(zooKeeper);
        } catch (KeeperException e) {
            e.printStackTrace();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
   /** @Author lyy
     * @Description //TODO 获取节点信息
     * @Date 14:57 2021/9/29
     * @Param 
     * @return 
    **/
    public void get(String key) {
        ZooKeeper zooKeeper = ZookeeperTest.getConntection();
        Stat stat = new Stat();
        String data = null;
        try {
            byte[] bytes = zooKeeper.getData(key, null, stat);
            data = new String(bytes, "gbk");
            log.info("当前节点信息:{}",data);
            ZookeeperTest.closeConnection(zooKeeper);
        } catch (KeeperException e) {
            e.printStackTrace();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
    }
    /** @Author lyy
      * @Description //TODO 修改节点信息
      * @Date 14:57 2021/9/29
      * @Param 
      * @return 
     **/
    public void modify(String key,String newValue) {
        ZooKeeper zooKeeper = ZookeeperTest.getConntection();
        Stat stat = new Stat();
        //version乐观锁概念,此处需要获取version信息，则需要先get拿到节点信息
        try {
            //获取节点(修改需要version信息)
            zooKeeper.getData(key, null, stat);
            //再修改
            zooKeeper.setData(key, newValue.getBytes(), stat.getVersion());
            ZookeeperTest.closeConnection(zooKeeper);
        } catch (KeeperException e) {
            e.printStackTrace();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
   /** @Author lyy
     * @Description //TODO 删除节点
     * @Date 14:57 2021/9/29
     * @Param 
     * @return 
    **/
    public void delete(String key) {
        ZooKeeper zooKeeper = ZookeeperTest.getConntection();
        Stat stat = new Stat();
        try {
            //获取节点(删除需要version信息)
            zooKeeper.getData(key, null, stat);
            //删除节点
            zooKeeper.delete(key, stat.getVersion());
            ZookeeperTest.closeConnection(zooKeeper);
        } catch (KeeperException e) {
            e.printStackTrace();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}