Zookeeper 入门看这篇就够了

 cd /usr/local/ get https://dlcdn.apache.org/zookeeper/zookeeper-3.7.0/apache-zookeeper-3.7.0-bin.tar.gz tar -zxvf apache-zookeeper-3.7.0-bin.tar.gzcd zookeeper-3.7.0/

cp conf/zoo_sample.cfg conf/zoo.cfg

./bin/zkServer.sh start

./bin/zkCli.sh 

ls /

create /zkMxn muxiaonong
 ls /[zkMxn, zookeeper]

get /zkMxn

set /zkMxn mxn666

 delete /zkMxn

<dependency>            <groupId>org.apache.zookeeper</groupId>           <artifactId>zookeeper</artifactId>        <version>3.6.3</version></dependency><!--junit单元测试--> <dependency>         <groupId>junit</groupId>         <artifactId>junit</artifactId>         <version>4.13.2</version>         <scope>runtime</scope>  </dependency>

  public ZooKeeper(String connectString, int sessionTimeout, Watcher watcher) throws IOException {        this(connectString, sessionTimeout, watcher, false);    }

Zookeeper zkClient = "";String connectStr = "192.168.2.1:2181";zkClient = new ZooKeeper(connectStr, 5000, new Watcher() {    @Override    public void process(WatchedEvent watchedEvent) { }});

public String create(String path, byte[] data, List<ACL> acl, CreateMode createMode) throws KeeperException, InterruptedException {}

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 **/@Slf4jpublic 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();        }
    }}