准备：

要么使用maven，要么手动引入zookeeper-3.4.6.jar和zk包lib文件夹下的jar包，slf4j-api-1.6.1.jar等

示例代码：

同步接口：

package raw_client;import java.io.IOException;
import java.util.List;
import java.util.concurrent.CountDownLatch;import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.Watcher.Event.EventType;
import org.apache.zookeeper.Watcher.Event.KeeperState;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.Stat;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;public class SyncApi implements Watcher
{private static CountDownLatch connectedSemaphore = new CountDownLatch(1);private static Stat stat = new Stat();private static final Logger log = LoggerFactory.getLogger(SyncApi.class);static ZooKeeper zk = null;static String path = "/zk_test";public static void main(String[] args) throws IOException, InterruptedException, KeeperException{// ----------------------连接---------------------------// 直接连连不上 state: Expiredlong sessionID = 1111111;String sessionPWD = "s1_pwd";SyncApi sa = new SyncApi();zk = new ZooKeeper("127.0.0.1:2181", 5000, sa, sessionID, sessionPWD.getBytes());log.info("ZooKeeper state: " + zk.getState());ZooKeeper zk1 = new ZooKeeper("127.0.0.1:2181", 5000, sa);long sessionId = zk1.getSessionId();byte[] passwd = zk1.getSessionPasswd();connectedSemaphore.await();log.info("ZooKeeper session established.");// 错误的session state: Expiredzk = new ZooKeeper("127.0.0.1:2181", 5000, sa, 1l, "test".getBytes());// 正确的session state: SyncConnectedzk = new ZooKeeper("127.0.0.1:2181", 5000, sa, sessionId, passwd);zk.exists(path, true);//----------------------------创建节点------------------------String pPath = zk.create(path, "fad".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);// 下面这行报NodeExistsException//        zk.create(path, "fad".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL);String esPath = zk.create(path, "fad".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL_SEQUENTIAL);String psPath = zk.create(path, "fad".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT_SEQUENTIAL);/* java进程结束后，临时节点消失[zk: localhost:2181(CONNECTED) 29] ls /[zk_test0000000011, zookeeper, zk_test0000000010, zk_test][zk: localhost:2181(CONNECTED) 30] ls /[zk_test0000000011, zookeeper, zk_test]*///----------------------------删除节点------------------------zk.delete(psPath, -1);zk.delete(esPath, 0);// 下面这行报BadVersion//        zk.delete(pPath, 10);//----------------------------获取数据------------------------log.info(new String(zk.getData(path, sa, stat)));log.info("Signature: " + stat.signature() + " Ctime: " + stat.getCtime() + " Aversion: " + stat.getAversion()+ " Cversion: " + stat.getCversion() + " Czxid: " + stat.getCzxid() + " DataLength: "+ stat.getDataLength() + " Mtime: " + stat.getMtime() + " Mzxid: " + stat.getMzxid() + " NumChildren: "+ stat.getNumChildren() + " Version: " + stat.getVersion() + " Pzxid: " + stat.getPzxid());//----------------------------更新数据------------------------// 测试watcher,下面这行触发NodeDataChanged类型的事件zk.setData(path, "update123".getBytes(), 0);//----------------------------获取子节点------------------------List<String> childrenList = zk.getChildren(path, sa, stat);log.info(childrenList.toString());zk.create(path + "/c1", "c11111111".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);Thread.sleep(2000);// 清理数据// 如果有子节点，直接删除会报错：Directory not empty for /zk_test// 先删除子节点zk.delete(path + "/c1", -1);zk.delete(path, -1);Thread.sleep(2000);zk.close();//----------------------------AuthInfo------------------------String childPath = path + "/c1";connectedSemaphore = new CountDownLatch(1);zk = new ZooKeeper("127.0.0.1:2181", 5000, sa);zk.addAuthInfo("digest", "key:value1".getBytes());connectedSemaphore.await();// 这里ACL和上面不同，否则加了AuthInfo也没有效果zk.create(path, "f".getBytes(), Ids.CREATOR_ALL_ACL, CreateMode.PERSISTENT);Thread.sleep(1000);zk.create(childPath, "c".getBytes(), Ids.CREATOR_ALL_ACL, CreateMode.PERSISTENT);Thread.sleep(1000);// 认证失败不可以删除子节点try{connectedSemaphore = new CountDownLatch(1);ZooKeeper zk2 = new ZooKeeper("127.0.0.1:2181", 5000, sa);connectedSemaphore.await();// NoAuth for /zk_test/c1zk2.delete(childPath, -1);}catch (Exception e){log.info("delete node " + path + "c1" + " fail: " + e.getMessage());}// 认证成功可以删除子节点connectedSemaphore = new CountDownLatch(1);ZooKeeper zk3 = new ZooKeeper("127.0.0.1:2181", 5000, sa);connectedSemaphore.await();zk3.addAuthInfo("digest", "key:value1".getBytes());zk3.delete(childPath, -1);log.info("deleted node " + childPath);// 节点本身无法限制权限connectedSemaphore = new CountDownLatch(1);ZooKeeper zk4 = new ZooKeeper("127.0.0.1:2181", 5000, sa);connectedSemaphore.await();zk4.delete(path, -1);log.info("deleted node " + path);Thread.sleep(Integer.MAX_VALUE);}@Overridepublic void process(WatchedEvent event){log.info("----------------");log.info("event: {}", event);log.info("path: {}", event.getPath());log.info("state: {}", event.getState());log.info("type: {}", event.getType());log.info("----------------");try{if (KeeperState.SyncConnected == event.getState()){if (event.getType() == EventType.None && null == event.getPath()){connectedSemaphore.countDown();}else if (event.getType() == EventType.NodeDataChanged){log.info(new String(zk.getData(event.getPath(), true, stat)));log.info(stat.getCzxid() + "," + stat.getMzxid() + "," + stat.getVersion());}else if (event.getType() == EventType.NodeChildrenChanged){List<String> childrenList = zk.getChildren(path, false);log.info("changed child: " + childrenList.toString());}else if (EventType.NodeCreated == event.getType()){log.info("Node(" + event.getPath() + ")Created");zk.exists(event.getPath(), true);}else if (EventType.NodeDeleted == event.getType()){log.info("Node(" + event.getPath() + ")Deleted");zk.exists(event.getPath(), true);}}}catch (Exception e){log.error(e.toString());}}
}

异步接口：

package raw_client;import java.io.IOException;
import java.util.List;
import java.util.concurrent.CountDownLatch;import org.apache.zookeeper.AsyncCallback;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.Watcher.Event.EventType;
import org.apache.zookeeper.Watcher.Event.KeeperState;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.data.Stat;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;public class AsyncApi implements Watcher
{private static CountDownLatch connectedSemaphore = new CountDownLatch(1);private static Stat stat = new Stat();static ZooKeeper zk = null;private static final Logger log = LoggerFactory.getLogger(AsyncApi.class);public static void main(String[] args) throws IOException, InterruptedException, KeeperException{zk = new ZooKeeper("127.0.0.1:2181", 5000, new AsyncApi());connectedSemaphore.await();//----------------------------创建节点------------------------String path = "/zk_test";zk.create(path, "main".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT, new MyStringCallback(), "contex");//----------------------------获取数据------------------------zk.getData(path, true, new MYDataCallback(), null);//----------------------------更新数据------------------------zk.setData(path, "childdata".getBytes(), 0);//----------------------------获取子节点------------------------zk.create(path + "/c1","child".getBytes(),Ids.OPEN_ACL_UNSAFE,CreateMode.PERSISTENT,new MyStringCallback(),"contex");zk.getChildren(path, true, new MyChildren2Callback(), "ctx");zk.getChildren(path, true, new MyChildrenCallback(), "ctx");//----------------------------删除节点------------------------Thread.sleep(2000);zk.delete(path + "/c1", -1);zk.delete(path, -1, new MyVoidCallback(), "ctx");Thread.sleep(Integer.MAX_VALUE);}@Overridepublic void process(WatchedEvent event){log.info("event: {}", event);log.info("path: {}", event.getPath());log.info("state: {}", event.getState());log.info("type: {}", event.getType());if (KeeperState.SyncConnected == event.getState()){if (event.getType() == EventType.None && null == event.getPath()){connectedSemaphore.countDown();}else if (event.getType() == EventType.NodeDataChanged){try{log.info(new String(zk.getData(event.getPath(), true, stat)));log.info(stat.getCzxid() + "," + stat.getMzxid() + "," + stat.getVersion());}catch (Exception e){}}}}}class MyStringCallback implements AsyncCallback.StringCallback
{private static final Logger log = LoggerFactory.getLogger(MyStringCallback.class);@Overridepublic void processResult(int rc, String path, Object ctx, String name){log.info("Create path result: [" + rc + ", " + path + ", " + ctx + ", real path name: " + name);}
}class MyVoidCallback implements AsyncCallback.VoidCallback
{private static final Logger log = LoggerFactory.getLogger(MyVoidCallback.class);@Overridepublic void processResult(int rc, String path, Object ctx){log.info("delete path result: " + rc + ", " + path + ", " + ctx);}
}class MYDataCallback implements AsyncCallback.DataCallback
{private static final Logger log = LoggerFactory.getLogger(MYDataCallback.class);@Overridepublic void processResult(int rc, String path, Object ctx, byte[] data, Stat stat){log.info(rc + ", " + path + ", " + new String(data));log.info(stat.getCzxid() + "," + stat.getMzxid() + "," + stat.getVersion());}
}class MyChildren2Callback implements AsyncCallback.Children2Callback
{private static final Logger log = LoggerFactory.getLogger(MyChildren2Callback.class);@Overridepublic void processResult(int rc, String path, Object ctx, List<String> children, Stat stat){log.info("Get Children znode result: [response code: " + rc + ", param path: " + path + ", ctx: "+ ctx + ", children list: " + children + ", stat: " + stat);}
}class MyChildrenCallback implements AsyncCallback.ChildrenCallback
{private static final Logger log = LoggerFactory.getLogger(MyChildrenCallback.class);@Overridepublic void processResult(int rc, String path, Object ctx, List<String> children){log.info("Get Children znode result: [response code: " + rc + ", param path: " + path + ", ctx: "+ ctx + ", children list: " + children);}
}