Zookeeper实战之嵌入式运行Zookeeper单机模式

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很多使用Zookeeper的情景是需要我们嵌入Zookeeper作为自己的分布式应用系统的一部分来提供分布式服务，此时我们需要通过程序的方式来启动Zookeeper。此时可以通过Zookeeper API的ZooKeeperServerMain类来启动Zookeeper服务。

下面是一个单机模式下启动Zookeeper服务的例子

package my.zookeeperstudy.server; import org.apache.zookeeper.*;import org.apache.zookeeper.server.ServerConfig;import org.apache.zookeeper.server.ZooKeeperServerMain;import org.apache.zookeeper.server.quorum.QuorumPeerConfig; import java.io.File;import java.io.IOException;import java.util.List;import java.util.Properties; public class StandaloneZKServer {     public static void main(String[] args) throws Exception {        Properties props = new Properties();        props.setProperty("tickTime", "2000");        props.setProperty("dataDir", new File(System.getProperty("java.io.tmpdir"), "zookeeper").getAbsolutePath());        props.setProperty("clientPort", "2181");        props.setProperty("initLimit", "10");        props.setProperty("syncLimit", "5");         QuorumPeerConfig quorumConfig = new QuorumPeerConfig();        try {            quorumConfig.parseProperties(props);        } catch(Exception e) {            throw new RuntimeException(e);        }         final ZooKeeperServerMain zkServer = new ZooKeeperServerMain();        final ServerConfig config = new ServerConfig();        config.readFrom(quorumConfig);        zkServer.runFromConfig(config);    } }

客户端例子如下

package my.zookeeperstudy.server; import org.apache.zookeeper.*;import java.util.List; public class Client {    public static void main(String[] args) throws Exception {        ZooKeeper zk = new ZooKeeper("localhost:2181", 10000,                new Watcher() {                    public void process(WatchedEvent event) {                        System.out.println("event: " + event.getType());                    }                });         System.out.println(zk.getState());         zk.create("/myApps", "myAppsData".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);        zk.create("/myApps/App1", "App1Data".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);        zk.create("/myApps/App2", "App2Data".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);        zk.create("/myApps/App3", "".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);        zk.setData("/myApps/App3","App3Data".getBytes(), -1);         System.out.println(zk.exists("/myApps", true));        System.out.println(new String(zk.getData("/myApps", true, null)));         List<String> children = zk.getChildren("/myApps", true);        for (String child : children) {            System.out.println(new String(zk.getData("/myApps/" + child, true, null)));            zk.delete("/myApps/" + child,-1);        }         zk.delete("/myApps",-1);         zk.close();    }}

测试
首先启动StandaloneZKServer类来启动Zookeeper服务，然后运行Client类来连接Zookeeper并操作数据。

原文链接：Zookeeper实战之嵌入式运行Zookeeper单机模式

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