基于ZkClient往zookeeper分布式集群节点写入数据

╰半橙微兮° 2024-04-17 05:33 65阅读 0赞

zookeeper自身的ZooKeeper构建一个连接，然后往zookeeper节点写入数据，但是代码写法略显复杂。现在使用github上的一个开源项目ZkClient

[https://github.com/sgroschupf/zkclient][https_github.com_sgroschupf_zkclient]

可以大大简化往zookeeper分布式集群中的节点写入数据的复杂度。

首先需要在pom.xml添加引用：

<dependencies>
            <dependency>
                <groupId>org.apache.zookeeper</groupId>
                <artifactId>zookeeper</artifactId>
                <version>3.5.5</version>
            </dependency>
    
            <dependency>
                <groupId>com.github.sgroschupf</groupId>
                <artifactId>zkclient</artifactId>
                <version>0.1</version>
            </dependency>
    
            <dependency>
                <groupId>org.apache.logging.log4j</groupId>
                <artifactId>log4j-core</artifactId>
                <version>2.12.1</version>
            </dependency>
        </dependencies>

Java代码程序：

import org.I0Itec.zkclient.IZkChildListener;
    import org.I0Itec.zkclient.IZkDataListener;
    import org.I0Itec.zkclient.ZkClient;
    import org.apache.zookeeper.*;
    
    import java.util.List;
    
    public class Main {
        public static void main(String[] args) {
            //初始化log4j，zookeeper否则报错。
            org.apache.log4j.BasicConfigurator.configure();
    
            try {
                Main m = new Main();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    
        public Main() throws Exception {
            String ip = "localhost";
            String addrs = ip + ":2181," + ip + ":2182," + ip + ":2183";
    
            //连接zookeeper服务器。
            //addrs是一批地址，如果其中某一个服务器挂掉，其他仍可用。
            ZkClient zkClient = new ZkClient(addrs);
            //zkClient.connect(300 * 1000, new MyWatcher());
    
            System.out.println("连接建立");
    
            String node = "/zhang_phil_node_2";
    
            //数据变化监听。
            zkClient.subscribeDataChanges(node, new IZkDataListener() {
                @Override
                public void handleDataChange(String dataPath, Object data) throws Exception {
                    System.out.println("handleDataChange:" + dataPath);
                    System.out.println("handleDataChange:" + data.toString());
                }
    
                @Override
                public void handleDataDeleted(String dataPath) throws Exception {
    
                }
            });
    
            zkClient.subscribeChildChanges(node, new IZkChildListener() {
                @Override
                public void handleChildChange(String parentPath, List<String> currentChilds) throws Exception {
                    System.out.println("handleChildChange:" + parentPath);
                    for (String c : currentChilds) {
                        System.out.println("handleChildChange:" + c);
                    }
                }
            });
    
            if (!zkClient.exists(node)) {
                zkClient.create(node, "hello,world! 2", CreateMode.PERSISTENT);
            }
    
            String s = zkClient.readData(node);
            System.out.println(s);
        }
    
        
        /*
        private class MyWatcher implements Watcher {
            @Override
            public void process(WatchedEvent event) {
                if (event.getState() == Event.KeeperState.SyncConnected) {
                    System.out.println("状态:" + Event.KeeperState.SyncConnected);
                }
            }
        }
         */
    }

程序运行后，用zookeeper提供的命令行进入节点查看数据情况：

![20190822164716139.png][]

表明写入成功。

乱码是序列号导致。用ZkClient读取出来的数据仍然是：

hello,world! 2

[https_github.com_sgroschupf_zkclient]: https://github.com/sgroschupf/zkclient
[20190822164716139.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/11/30bcdf1db9874dce96f6a27f2441dedf.png