zookeeper示例

comp-example/pom.xml

@@ -27,8 +27,15 @@
			<artifactId>ipu-cache</artifactId>
			<version>${ipu}</version>
		</dependency>
		<dependency>
			<groupId>org.apache.zookeeper</groupId>
			<artifactId>zookeeper</artifactId>
			<version>3.4.12</version>
		</dependency>
	</dependencies>
	
	<build>
		<plugins>
			<plugin>

comp-example/src/test/java/com/ai/ipu/example/zookeeper/ZookeeperExample.java

@@ -1,5 +1,81 @@
package com.ai.ipu.example.zookeeper;
import org.apache.zookeeper.*;
import java.io.IOException;
import java.util.List;
public class ZookeeperExample {
    // 会话超时时间，设置为与系统默认时间一致
    private static final int SESSION_TIMEOUT = 2 * 1000;
    // 创建 ZooKeeper 实例
    private ZooKeeper zk;
    // 创建 Watcher 实例
    private Watcher wh = new Watcher() {
        public void process(WatchedEvent event) {
            System.out.println("触发了WatchedEvent的事件 >>> " + event.toString());
        }
    };
    // 初始化 ZooKeeper 实例
    private void createZKInstance() throws IOException {
        // 连接到ZK服务，多个可以用逗号分割写
        zk = new ZooKeeper("47.105.160.21:2181,47.105.160.21:2182,47.105.160.21:2183", ZookeeperExample.SESSION_TIMEOUT, this.wh);
    }
    private void showNodes(String path) throws InterruptedException, KeeperException {
        List<String> list = zk.getChildren(path, this.wh);
        int i = 1;
        for (String node : list) {
            System.out.println("(" + i + ")" + node);
            i++;
        }
    }
    
    private void ZKOperations() throws InterruptedException, KeeperException {
        System.out.println("初始节点：");
        showNodes("/");
        System.out.println("---------------------------------");
        System.out.println("创建 ZooKeeper 节点 (znode ： myzktest, 数据： myData2 ，权限： OPEN_ACL_UNSAFE ，节点类型： Persistent");
        zk.create("/myzktest", "myData2".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
        System.out.println("查看是否创建成功： ");
        System.out.println("当前节点：");
        showNodes("/");
        System.out.println("/myzktest的数据为：");
        System.out.println(new String(zk.getData("/myzktest", this.wh, null)));// 添加Watch
        System.out.println("---------------------------------");
        System.out.println("修改节点数据 ");
        zk.setData("/myzktest", "liutong".getBytes(), -1);
        System.out.println("/myzktest的数据为：");
        System.out.println(new String(zk.getData("/myzktest", false, null)));
        System.out.println("---------------------------------");
        // 这里再次进行修改，则不会触发Watch事件，这就是我们验证ZK的一个特性“一次性触发”，也就是说设置一次监视，只会对下次操作起一次作用。
        System.out.println("3再次修改节点数据 ");
        zk.setData("/myzktest", "liutong2".getBytes(), -1);
        System.out.println("/myzktest的数据为：");
        System.out.println(new String(zk.getData("/myzktest", false, null)));
        System.out.println("---------------------------------");
        System.out.println("删除节点 ");
        zk.delete("/myzktest", -1);
        System.out.println(" 节点状态： [" + zk.exists("/myzktest", false) + "]");
        showNodes("/");
    }
    private void ZKClose() throws InterruptedException {
        zk.close();
    }
    public static void main(String[] args) throws IOException, InterruptedException, KeeperException {
        ZookeeperExample dm = new ZookeeperExample();
        dm.createZKInstance();
        dm.ZKOperations();
        dm.ZKClose();
    }
}