Zookeeper客户端zkClient和curator的操作

Posted 2021-06-26 微瞰技术

zkClient操作

基本增删改查代码如下

public class createSession {
    public static void main(String[] args) {
        ZkClient zkClient = new ZkClient("119.45.52.68:2181");
        System.out.println("connect success");
    }
}

public class CreateNode {

    public static void main(String[] args) {
        ZkClient zkClient = new ZkClient("119.45.52.68:2181");
        System.out.println("connect success");
        //true代表可以递归创建目录
        zkClient.createPersistent("/zkclient/persistent/children",true);
        System.out.println("create node success");
    }
}

public class DeleteNode {
    public static void main(String[] args) {
        ZkClient zkClient = new ZkClient("119.45.52.68:2181");
        zkClient.deleteRecursive("/zkclient");
        System.out.println("success delete node");
    }
}

public class GetChildrenChanged {
    public static void main(String[] args) throws Exception{
        ZkClient zkClient = new ZkClient("119.45.52.68:2181");
        zkClient.createPersistent("/zkClient");
        Thread.sleep(1000);
        List<String> children = zkClient.getChildren("/zkClient");
        System.out.println(children);
        zkClient.subscribeChildChanges("/zkClient", new IZkChildListener() {
            @Override
            public void handleChildChange(String parentPath, List<String> currentChilds) throws Exception {
                System.out.println("父路径"+parentPath+"当前子路径的"+currentChilds);
            }
        });
        zkClient.createPersistent("/zkClient/child1");
        Thread.sleep(1000);
        zkClient.delete("/zkClient/child1");
        Thread.sleep(Integer.MAX_VALUE);
    }
}

public class GetNodeData {
    public static void main(String[] args) throws Exception{
        String path = "/zkclient-node";
        ZkClient zkClient = new ZkClient("119.45.52.68:2181");
        boolean exist = zkClient.exists(path);
        if (!exist){
            zkClient.createEphemeral(path,"123");
        }
        zkClient.subscribeDataChanges(path, new IZkDataListener() {
            @Override
            public void handleDataChange(String dataPath, Object data) throws Exception {
                System.out.println(dataPath+"节点内容被更新"+data);
            }

            @Override
            public void handleDataDeleted(String dataPath) throws Exception {
                System.out.println(dataPath+"节点内容被删除");

            }
        });
        Object o = zkClient.readData(path);
        System.out.println(o);

        zkClient.writeData(path,"4567");
        Thread.sleep(2000);

        zkClient.delete(path);
        Thread.sleep(2000);
    }
}

curator操作api使用

public class CreateSession {
    public static void main(String[] args) {
        //curator第一种创建回话方式
        RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000,3);
        CuratorFramework curatorFramework = CuratorFrameworkFactory.newClient("119.45.52.68:2181",
                5000,3000,retryPolicy);
        curatorFramework.start();
        System.out.println("create session success");
        //第二种方式
        CuratorFramework client =CuratorFrameworkFactory.builder()
                .connectString("119.45.52.68:2181")
                .sessionTimeoutMs(5000)
                .sessionTimeoutMs(3000)
                .retryPolicy(retryPolicy)
                .namespace("base")
                .build();
        client.start();
        System.out.println("createe session2 success ");
    }
}


public class CreateNode {
    public static void main(String[] args) throws  Exception{
        RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000,3);
        CuratorFramework client = CuratorFrameworkFactory.builder()
                .connectString("119.45.52.68:2181")
                .sessionTimeoutMs(5000)
                .sessionTimeoutMs(3000)
                .retryPolicy(retryPolicy)
                //.namespace("base")
                .build();
        client.start();
        String path = "/curator/child1";
        client.create().creatingParentContainersIfNeeded()
                .withMode(CreateMode.PERSISTENT)
                .forPath(path,"init".getBytes());
        System.out.println("success create node");
    }
}


public class DeleteNode {
    public static void main(String[] args) throws Exception{
        RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000,3);
        CuratorFramework client = CuratorFrameworkFactory.builder()
                .connectString("119.45.52.68:2181")
                .sessionTimeoutMs(5000)
                .sessionTimeoutMs(3000)
                .retryPolicy(retryPolicy)
                //.namespace("base")
                .build();
        client.start();
        String path = "/curator";
        client.delete().deletingChildrenIfNeeded().withVersion(-1).forPath(path);
        System.out.println("delete node success ");
    }
}


public class GetNodeData {
    public static void main(String[] args) throws Exception{
        RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000,3);
        CuratorFramework client = CuratorFrameworkFactory.builder()
                .connectString("119.45.52.68:2181")
                .sessionTimeoutMs(5000)
                .sessionTimeoutMs(3000)
                .retryPolicy(retryPolicy)
                //.namespace("base")
                .build();
        client.start();
        String path = "/curator/child1";
        client.create().creatingParentContainersIfNeeded()
                .withMode(CreateMode.PERSISTENT)
                .forPath(path,"init".getBytes());
        System.out.println("success create node");
        Stat stat = new Stat();
        byte [] data = client.getData().storingStatIn(stat).forPath(path);
        System.out.println("数据为"+new String(data));
    }
}


public class UpdateNodeData {
    public static void main(String[] args) throws Exception{
        RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000,3);
        CuratorFramework client = CuratorFrameworkFactory.builder()
                .connectString("119.45.52.68:2181")
                .sessionTimeoutMs(5000)
                .sessionTimeoutMs(3000)
                .retryPolicy(retryPolicy)
                //.namespace("base")
                .build();
        client.start();
        String path = "/curator/child1";
//        client.create().creatingParentContainersIfNeeded()
//                .withMode(CreateMode.PERSISTENT)
//                .forPath(path,"init".getBytes());
//        System.out.println("success create node");
        Stat stat = new Stat();
        byte [] data = client.getData().storingStatIn(stat).forPath(path);
        System.out.println("数据为"+new String(data));

        int version = client.setData().withVersion(stat.getVersion()).forPath(path).getVersion();
        System.out.println("update node "+path+" version "+version);
        client.setData().withVersion(stat.getVersion()).forPath(path).getAversion();
    }
}

最后一行代码会报错，原因是不能设置同样的数据版本。

除了上述的两种zkclient和curatir的常用操作。还有一些其他操作都可以去尝试
代码的地址为https://github.com/zhendiao/deme-code/tree/main/zk

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