zookeeper api 

--原生api

CreateSession 连接zookeeper

package lddxfs.zkstudy.zkdemo.test001;import lddxfs.zkstudy.zkdemo.Constant;import org.apache.zookeeper.WatchedEvent;import org.apache.zookeeper.Watcher;import org.apache.zookeeper.ZooKeeper;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/20 */public class CreateSession {    private static ZooKeeper zk;    public static void main(String[] args) throws Exception {        zk = new ZooKeeper(Constant.CONNECT_STRING, Constant.SESSION_TIMEOUT, new MyWatcher());       //Zookeeper是API提供的1个类，我们连接zk集群，进行相应的znode操作，都是通过ZooKeeper的实例进行，这个实例就是zk client，和命令行客户端是同样的角色        //Zookeeper实例的创建需要传递3个参数        //connectString 代表要连接zk集群服务，通过逗号分隔        Thread.sleep(Integer.MAX_VALUE);    }    static class MyWatcher implements Watcher {        public void process(WatchedEvent event) {//            这个方法只会调用一次，在这个session建立完成调用            if (event.getState() == Event.KeeperState.SyncConnected) {                //连接建立事件的处理                System.out.println("Event:" + event);                System.out.println("=========Client Connected to zookeeper==========");            }        }    }}

CreateNode 创建znode

package lddxfs.zkstudy.zkdemo.test002;import lddxfs.zkstudy.zkdemo.Constant;import org.apache.zookeeper.*;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/20 */public class CreateNode implements Watcher {    private static ZooKeeper zk;    public static void main(String[] args) throws Exception {        zk = new ZooKeeper(Constant.CONNECT_STRING, Constant.SESSION_TIMEOUT, new CreateNode());        Thread.sleep(Integer.MAX_VALUE);    }    public void process(WatchedEvent event) {       //Client段处理连接建立事件，处理动作为添加1个永久节点        if(event.getState()==Event.KeeperState.SyncConnected){            //创建znode节点            try {                createNodeSync();            } catch (KeeperException e) {                e.printStackTrace();            } catch (InterruptedException e) {                e.printStackTrace();            }        }    }    //create node, synchronized    private  void  createNodeSync() throws KeeperException, InterruptedException {        System.out.println("Create node with Sync mode");        String path =zk.create("/node_by_java","123".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);        System.out.println("New Node added: "+path);    }}

GetChildrenSync 获取子节点不注册watch

package lddxfs.zkstudy.zkdemo.test003;import lddxfs.zkstudy.zkdemo.Constant;import org.apache.zookeeper.KeeperException;import org.apache.zookeeper.WatchedEvent;import org.apache.zookeeper.Watcher;import org.apache.zookeeper.ZooKeeper;import java.util.List;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/20 */public class GetChildrenSync implements Watcher {    private  static ZooKeeper zk;    public static void main(String[] args) throws  Exception {        zk=new ZooKeeper(Constant.CONNECT_STRING,Constant.SESSION_TIMEOUT,new GetChildrenSync());        Thread.sleep(Integer.MAX_VALUE);    }    public void process(WatchedEvent event) {        //只在连接建立后，查询 /的子节点列表        if(event.getState()==Event.KeeperState.SyncConnected){            //查询子节点列表            try {                getChildranSync();            } catch (KeeperException e) {                e.printStackTrace();            } catch (InterruptedException e) {                e.printStackTrace();            }        }    }    //get children ,synchronized    private  void getChildranSync() throws KeeperException, InterruptedException {        System.out.println("Get Childran in sync mode");        //false ,不关注子节点列表的变更事件（不注册watcher）        List
      
        children=zk.getChildren("/",false);        System.out.println("Children list of /: "+children);    }}
      

GetChildrenSync 获取子节点注册watch

package lddxfs.zkstudy.zkdemo.test004;import lddxfs.zkstudy.zkdemo.Constant;import org.apache.zookeeper.KeeperException;import org.apache.zookeeper.WatchedEvent;import org.apache.zookeeper.Watcher;import org.apache.zookeeper.ZooKeeper;import java.io.IOException;import java.util.List;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/20 */public class GetChildrenSync implements Watcher {    private static ZooKeeper zk;    public static void main(String[] args) throws IOException, InterruptedException {        zk = new ZooKeeper(Constant.CONNECT_STRING, Constant.SESSION_TIMEOUT, new GetChildrenSync());        Thread.sleep(Integer.MAX_VALUE);    }    public void process(WatchedEvent event) {        //子节点列表变化 even的处理        if (event.getType() == Event.EventType.NodeChildrenChanged) {            //再次获取子节点列表            try {                //event.getPath()返回 哪个znode的子节点列表发生了变化                List
      
        childrens = zk.getChildren(event.getPath(), true);                System.out.println("NodeChildrenChanged childrens=" + childrens);            } catch (KeeperException e) {                e.printStackTrace();            } catch (InterruptedException e) {                e.printStackTrace();            }        } else if (event.getState() == Event.KeeperState.SyncConnected) {            try {                getChildrenSync();            } catch (KeeperException e) {                e.printStackTrace();            } catch (InterruptedException e) {                e.printStackTrace();            }        }    }    private void getChildrenSync() throws KeeperException, InterruptedException {        System.out.println("Get Children in sync mode");        List
       
         childrens = zk.getChildren("/", true);        System.out.println("Children list of / : " + childrens);    }}
       
      

DeleteNodeSync 删除znode

package lddxfs.zkstudy.zkdemo.test005;import lddxfs.zkstudy.zkdemo.Constant;import org.apache.zookeeper.KeeperException;import org.apache.zookeeper.WatchedEvent;import org.apache.zookeeper.Watcher;import org.apache.zookeeper.ZooKeeper;import java.io.IOException;import java.util.List;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/20 */public class DeleteNodeSync implements Watcher {    private  static ZooKeeper zk;    public static void main(String[] args) throws IOException, InterruptedException {        zk=new ZooKeeper(Constant.CONNECT_STRING,Constant.SESSION_TIMEOUT,new DeleteNodeSync());        Thread.sleep(Integer.MAX_VALUE);    }    public void process(WatchedEvent event) {        if(event.getState()== Event.KeeperState.SyncConnected){            if(event.getType()== Event.EventType.None&&event.getPath()==null){                try {                    deleteNode("/nodeddd");                } catch (KeeperException e) {                    e.printStackTrace();                } catch (InterruptedException e) {                    e.printStackTrace();                }            }        }    }    private void  deleteNode(String path) throws KeeperException, InterruptedException {        System.out.println("Delete Node in sync mode");        zk.delete(path,-1);        System.out.println("Node delete :"+path);        List
      
        children=zk.getChildren("/",false);        System.out.println("Children list  of / is: "+children);    }}
      

SetDataSync设置数据

package lddxfs.zkstudy.zkdemo.test006;import lddxfs.zkstudy.zkdemo.Constant;import org.apache.zookeeper.*;import org.apache.zookeeper.data.Stat;import java.io.IOException;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/20 */public class SetDataSync implements Watcher {    private static ZooKeeper zk;    public static void main(String[] args) throws IOException, InterruptedException {        zk = new ZooKeeper(Constant.CONNECT_STRING, Constant.SESSION_TIMEOUT, new SetDataSync());        Thread.sleep(Integer.MAX_VALUE);    }    public void process(WatchedEvent event) {        if (event.getState() == Event.KeeperState.SyncConnected) {            if (event.getType() == Event.EventType.None && event.getPath() == null) {                try {                    String path = zk.create("/testdata", "12345".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);                    Stat stat = zk.setData(path, "zhonddd".getBytes(), -1);                    System.out.println("");                    byte[] datass = zk.getData(path, false, stat);                    System.out.println(new String(datass));                } catch (KeeperException e) {                    e.printStackTrace();                } catch (InterruptedException e) {                    e.printStackTrace();                }            }        }    }}

 

zkclient api

   --是GitHub上一个开源的ZooKeeper客户端 在原生Zookeeper API 接口上进行包装

CreateSession 连接zookeeper

package lddxfs.zkstudy.zkclientdemo.test001;import lddxfs.zkstudy.zkdemo.Constant;import org.I0Itec.zkclient.ZkClient;import org.I0Itec.zkclient.serialize.SerializableSerializer;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/21 *///zkclient 是GitHub上一个开源的ZooKeeper客户端 在原生Zookeeper API 接口上进行包装// 同时在内部实现了session超时重连 ，Watcher反复注册等功能public class CreateSession {    public static void main(String[] args) {        ZkClient zkClient=new ZkClient(Constant.CONNECT_STRING,Constant.SESSION_TIMEOUT,Constant.CONNECTION_TIMEOUT,new SerializableSerializer());        /**         * 1)和zookeeper原生API不同 通过zkclient API创建会话 需要提供session timeout，connection timeout两个定时器         * 2)同时要提供 1个序列化器实例，原因在于后续创建zonde节点时，写入的数据（java对象）会自动通过序列化器来转换为byte[]         * 3)同理 ，读取出的byte[] 的数据，也会自动通过序列化器直接转换为java对象         */    }}

CreateNode

package lddxfs.zkstudy.zkclientdemo.test002;import lddxfs.zkstudy.zkclientdemo.User;import lddxfs.zkstudy.zkdemo.Constant;import org.I0Itec.zkclient.ZkClient;import org.I0Itec.zkclient.serialize.SerializableSerializer;import org.apache.zookeeper.CreateMode;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/21 */public class CreateNode {    public static void main(String[] args) {        ZkClient zkClient=new ZkClient(Constant.CONNECT_STRING,Constant.SESSION_TIMEOUT,Constant.CONNECTION_TIMEOUT,new SerializableSerializer());        User user=new User();        //直接将数据user写入，自动序列化为byte[]        String path=  zkClient.create("/node_zkclient",user, CreateMode.PERSISTENT);        System.out.println("Create path is:"+path);        /**         * 通过客户端查看会是这样格式的数据         * [zk: 192.168.10.132:2185(CONNECTED) 3] get /node_zkclient         * ��sr lddxfs.zkstudy.zkclientdemo.User-U��t�'LidtLjava/lang/Integer;LnametLjava/lang/String;xppp         */    }}

WriteData

package lddxfs.zkstudy.zkclientdemo.test003;import lddxfs.zkstudy.zkclientdemo.User;import lddxfs.zkstudy.zkdemo.Constant;import org.I0Itec.zkclient.ZkClient;import org.I0Itec.zkclient.serialize.SerializableSerializer;import org.apache.zookeeper.CreateMode;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/21 */public class WriteData {    private static final String PATH = "/node_zkclient2";    public static void main(String[] args) {        ZkClient zkClient = new ZkClient(Constant.CONNECT_STRING, Constant.SESSION_TIMEOUT, Constant.CONNECTION_TIMEOUT, new SerializableSerializer());        User user = new User(1, "zhangsan");        zkClient.create(PATH, user, CreateMode.PERSISTENT);        user.setId(2);        user.setName("lisi");        zkClient.writeData(PATH, user);    }}

ReadData

package lddxfs.zkstudy.zkclientdemo.test004;import lddxfs.zkstudy.zkclientdemo.User;import lddxfs.zkstudy.zkdemo.Constant;import org.I0Itec.zkclient.ZkClient;import org.I0Itec.zkclient.serialize.SerializableSerializer;import org.apache.zookeeper.CreateMode;import org.apache.zookeeper.data.Stat;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/21 */public class ReadData {    private static final String PATH = "/node_zkclient3";    public static void main(String[] args) {        ZkClient zkClient = new ZkClient(Constant.CONNECT_STRING, Constant.SESSION_TIMEOUT, Constant.SESSION_TIMEOUT, new SerializableSerializer());        User user = new User(1, "wangwu");        String path = zkClient.create(PATH, user, CreateMode.PERSISTENT);        System.out.println("Create path is :" + path);        Stat stat = new Stat();        user = zkClient.readData(PATH, stat);        if (user != null) {            System.out.println(user);            System.out.println(stat);        }    }}

GetChildren

package lddxfs.zkstudy.zkclientdemo.test005;import lddxfs.zkstudy.zkclientdemo.User;import lddxfs.zkstudy.zkdemo.Constant;import org.I0Itec.zkclient.ZkClient;import org.I0Itec.zkclient.serialize.SerializableSerializer;import java.util.List;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/21 */public class GetChildren {    public static void main(String[] args) {        ZkClient zkClient=new ZkClient(Constant.CONNECT_STRING,Constant.SESSION_TIMEOUT,Constant.CONNECTION_TIMEOUT,new SerializableSerializer());        List
      
        children=zkClient.getChildren("/");        System.out.println("Children list of /:"+children);        //Children list of /:[testdata, node_zkclient3, dubbo, node_zkclient2, zookeeper, node_zkclient]    }}
      

NodeExist

package lddxfs.zkstudy.zkclientdemo.test006;import lddxfs.zkstudy.zkdemo.Constant;import org.I0Itec.zkclient.ZkClient;import org.I0Itec.zkclient.serialize.SerializableSerializer;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/21 * 判断节点是否存在 */public class NodeExist {    public static void main(String[] args) {        ZkClient zkClient = new ZkClient(Constant.CONNECT_STRING, Constant.SESSION_TIMEOUT, Constant.CONNECTION_TIMEOUT, new SerializableSerializer());        boolean exist = zkClient.exists("/dubbo");        System.out.println("Node exist status is:" + exist);        //Node exist status is:true    }}

订阅子节点列表发生变化

package lddxfs.zkstudy.zkclientdemo.test007;import lddxfs.zkstudy.zkdemo.Constant;import org.I0Itec.zkclient.ZkClient;import org.I0Itec.zkclient.serialize.SerializableSerializer;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/21 * 订阅子节点列表发生变化 */public class SubscribeChildren {    public static void main(String[] args) throws InterruptedException {        ZkClient zkClient=new ZkClient(Constant.CONNECT_STRING,Constant.SESSION_TIMEOUT,Constant.CONNECTION_TIMEOUT,new SerializableSerializer());        zkClient.subscribeChildChanges("/888",new ZkChildListener());        Thread.sleep(Integer.MAX_VALUE);        /**         * 使用Cli.sh连接zk         * [zk: 192.168.10.132:2185(CONNECTED) 6] create /888 888         * Created /888         * [zk: 192.168.10.132:2185(CONNECTED) 7] create /888/999 999         * Created /888/999         * [zk: 192.168.10.132:2185(CONNECTED) 8]         * 控制台输出         * Parent path is/888         * Current children:[]         * Parent path is/888         * Current children:[999]         */    }}

package lddxfs.zkstudy.zkclientdemo.test007;import org.I0Itec.zkclient.IZkChildListener;import java.util.List;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/21 */public class ZkChildListener implements IZkChildListener {    public void handleChildChange(String parentPath, List
      
        currentChilds) throws Exception {        System.out.println("Parent path is"+parentPath);        System.out.println("Current children:"+currentChilds);    }}
      

订阅数据变化

package lddxfs.zkstudy.zkclientdemo.test008;import lddxfs.zkstudy.zkdemo.Constant;import org.I0Itec.zkclient.ZkClient;import org.I0Itec.zkclient.serialize.BytesPushThroughSerializer;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/21 * 订阅数据变化 */public class SubscribeData {    public static void main(String[] args) throws InterruptedException {        //使用了新的序列化器，zk命令行写入的数据才能被检查        ZkClient zkClient = new ZkClient(Constant.CONNECT_STRING, Constant.SESSION_TIMEOUT, Constant.CONNECTION_TIMEOUT, new BytesPushThroughSerializer());        zkClient.subscribeDataChanges("/node_zkclient", new ZkDataListener());        Thread.sleep(Integer.MAX_VALUE);        /**         * [zk: 192.168.10.132:2185(CONNECTED) 10] set /node_zkclient ddd         * data change dataPath:/node_zkclient         * data change data:[B@11d2adb4         *         */    }}

package lddxfs.zkstudy.zkclientdemo.test008;import org.I0Itec.zkclient.IZkDataListener;/** * Author:lddxfs（lddxfs@qq.com;https://www.cnblogs.com/LDDXFS/） * Date:2018/10/21 */public class ZkDataListener implements IZkDataListener {    public void handleDataChange(String dataPath, Object data) throws Exception {        System.out.println("data change dataPath:"+dataPath);        System.out.println("data change data:"+data);    }    public void handleDataDeleted(String dataPath) throws Exception {        System.out.println("deleted data dataPath:"+dataPath);    }}