4.zookeeper3.5.7相关API操作

核心类 org.apache.zookeeper.ZooKeeper#ZooKeeper(java.lang.String, int, org.apache.zookeeper.Watcher)

public ZooKeeper(String connectString, int sessionTimeout, Watcher watcher)

    @Before
    public void init() throws Exception {
        zkClient = new ZooKeeper(zkServers, sessionTimeout, new Watcher() {
            @Override
            public void process(WatchedEvent watchedEvent) {
                log.info("事件类型:{} ,路径:{} ,状态:{} ", watchedEvent.getType(), watchedEvent.getPath(), watchedEvent.getState());
            }
        });
    }

核心类 org.apache.zookeeper.ZooKeeper#create(java.lang.String, byte[], java.util.List, org.apache.zookeeper.CreateMode)

public String create(final String path, byte data[], List acl,
            CreateMode createMode)

    
    @Test
    public void testCreateNode() throws KeeperException, InterruptedException {
        
        zkClient.create("/demo", "demoData".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
    }

核心类org.apache.zookeeper.ZooKeeper#getChildren(java.lang.String, boolean)

public List getChildren(String path, boolean watch);

public List getChildren(final String path, Watcher watcher);

    @Test
    public void testWatchNode() throws KeeperException, InterruptedException {
        List children = zkClient.getChildren("/demo", true);
        log.info(String.join(",", children));
        Thread.sleep(600 * 1000);
    }

核心类org.apache.zookeeper.ZooKeeper#getData(java.lang.String, org.apache.zookeeper.Watcher, org.apache.zookeeper.data.Stat)

public byte[] getData(final String path, Watcher watcher, Stat stat)
        throws KeeperException, InterruptedException

    @Test
    public void testGetData() throws KeeperException, InterruptedException {
        Stat stat = new Stat();

        byte[] data = zkClient.getData("/demo", new Watcher() {
            @SneakyThrows
            @Override
            public void process(WatchedEvent watchedEvent) {
                log.info("getData 事件类型:{} ,路径:{} ,状态:{} ", watchedEvent.getType(), watchedEvent.getPath(), watchedEvent.getState());
                byte[] changeData = zkClient.getData("/demo", true, null);
                log.info("节点变化数据:{}", new String(changeData));
            }
        }, stat);
        log.info("节点数据:{}", new String(data));
        Thread.sleep(600 * 1000);
    }

核心类org.apache.zookeeper.ZooKeeper#exists(java.lang.String, boolean)

public Stat exists(String path, boolean watch) throws KeeperException;
// 重载方法
public Stat exists(final String path, Watcher watcher)

    
    @Test
    public void testExist() throws Exception {
        Stat exists = zkClient.exists("/demo", false);
        log.info(exists.toString());
    }

@Slf4j
public class ZkClientDemo {

    private static String zkServers = "node1:2181";

    private static int sessionTimeout = 2000;

    private static ZooKeeper zkClient;

    @Before
    public void init() throws Exception {
        zkClient = new ZooKeeper(zkServers, sessionTimeout, new Watcher() {
            @Override
            public void process(WatchedEvent watchedEvent) {
                log.info("事件类型:{} ,路径:{} ,状态:{} ", watchedEvent.getType(), watchedEvent.getPath(), watchedEvent.getState());
            }
        });
    }

    
    @Test
    public void testCreateNode() throws KeeperException, InterruptedException {
        
        zkClient.create("/demo", "demoData".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
    }

    
    @Test
    public void testWatchNode() throws KeeperException, InterruptedException {
        List children = zkClient.getChildren("/demo", true);
        log.info(String.join(",", children));
        Thread.sleep(600 * 1000);
    }

    @Test
    public void testGetData() throws KeeperException, InterruptedException {
        Stat stat = new Stat();

        byte[] data = zkClient.getData("/demo", new Watcher() {
            @SneakyThrows
            @Override
            public void process(WatchedEvent watchedEvent) {
                log.info("getData 事件类型:{} ,路径:{} ,状态:{} ", watchedEvent.getType(), watchedEvent.getPath(), watchedEvent.getState());
                byte[] changeData = zkClient.getData("/demo", true, null);
                log.info("节点变化数据:{}", new String(changeData));
            }
        }, stat);
        log.info("节点数据:{}", new String(data));
        Thread.sleep(600 * 1000);
    }


    
    @Test
    public void testExist() throws Exception {
        Stat exists = zkClient.exists("/demo", false);
        log.info(exists.toString());
    }
}