ZooKeeper(3.4.5) - 原生 API 的简单示例
一、创建会话
1. 创建一个基本的ZooKeeper会话实例
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.Watcher.Event.KeeperState; /**
* 创建一个基本的ZooKeeper会话实例
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception {
final CountDownLatch connectedSignal = new CountDownLatch(1); /**
* ZooKeeper客户端和服务器会话的建立是一个异步的过程
* 构造函数在处理完客户端的初始化工作后立即返回，在大多数情况下，并没有真正地建立好会话
* 当会话真正创建完毕后，Zookeeper服务器会向客户端发送一个事件通知
*/
ZooKeeper zk = new ZooKeeper("192.168.1.109:2181", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
connectedSignal.countDown();
}
}
});
System.out.println("State1: " + zk.getState()); // CONNECTING connectedSignal.await();
System.out.println("State2: " + zk.getState()); // CONNECTED zk.close();
System.out.println("State3: " + zk.getState()); // CLOSED
} }
2. 创建一个复用sessionId和sessionPasswd的Zookeeper对象示例
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.Watcher.Event.KeeperState; /**
* 创建一个复用sessionId和sessionPasswd的ZooKeeper对象示例
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
ZooKeeper zk = new ZooKeeper("192.168.1.109:2181", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
connectedSignal.countDown();
}
}
}); connectedSignal.await();
long sessionId = zk.getSessionId();
byte[] passwd = zk.getSessionPasswd();
zk.close(); final CountDownLatch anotherConnectedSignal = new CountDownLatch(1);
ZooKeeper newZk = new ZooKeeper(
"192.168.1.109:2181",
5000,
new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
anotherConnectedSignal.countDown();
}
}
},
sessionId,
passwd); anotherConnectedSignal.await();
newZk.close();
} }
二、创建节点
1. 使用同步API创建一个ZNode节点
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.Watcher.Event.KeeperState;
import org.apache.zookeeper.ZooDefs.Ids; /**
* 使用同步API创建一个ZNode节点
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
ZooKeeper zk = new ZooKeeper("192.168.1.109:2181", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
connectedSignal.countDown();
}
}
});
connectedSignal.await(); String path = zk.create(
"/zk-huey",
"hello".getBytes(),
Ids.OPEN_ACL_UNSAFE,
CreateMode.PERSISTENT
);
System.out.println(path + " is created."); zk.close();
} }
2. 使用异步API创建一个ZNode节点
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.AsyncCallback;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.Watcher.Event.KeeperState;
import org.apache.zookeeper.ZooDefs.Ids; /**
* 使用异步API创建一个ZNode节点
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
ZooKeeper zk = new ZooKeeper("192.168.1.109:2181", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
connectedSignal.countDown();
}
}
});
connectedSignal.await(); zk.create(
"/zk-huey",
"hello".getBytes(),
Ids.OPEN_ACL_UNSAFE,
CreateMode.PERSISTENT_SEQUENTIAL,
new AsyncCallback.StringCallback() {
@Override
public void processResult(int rc, String path, Object ctx, String name) {
// 服务器响应吗
System.out.println("ResultCode: " + rc);
// 接口调用时传入API的数据节点的路径参数值
System.out.println("Znode: " + path);
// 接口调用时传入API的ctx参数值
System.out.println("Context: " + (String)ctx);
// 实际在服务端创建的节点名
System.out.println("Real Path: " + name);
}
},
"The Context"
); zk.close();
} }
三、删除节点
1. 使用同API删除一个ZNode节点
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.Watcher.Event.KeeperState; /**
* 使用同步API删除一个ZNode节点
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
ZooKeeper zk = new ZooKeeper("192.168.1.109:2181", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
connectedSignal.countDown();
}
}
});
connectedSignal.await(); zk.delete("/zk-huey", -1); zk.close();
} }
2. 使用异步API删除一个ZNode节点
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.AsyncCallback;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.Watcher.Event.KeeperState; /**
* 使用异步API删除一个ZNode节点
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
ZooKeeper zk = new ZooKeeper("192.168.1.109:2181", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
connectedSignal.countDown();
}
}
});
connectedSignal.await(); zk.delete(
"/zk-huey",
-1,
new AsyncCallback.VoidCallback() {
@Override
public void processResult(int rc, String path, Object ctx) {
System.out.println("ResultCode: " + rc);
System.out.println("Znode: " + path);
System.out.println("Context: " + (String)ctx);
}
},
"The Context"
); zk.close();
} }
四、获取子节点列表
1. 使用同步API获取子节点列表
package com.huey.dream.demo; 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.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; /**
* 使用同步API获取子节点列表
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
final ZooKeeper zk = new ZooKeeper("192.168.1.109:2182", 5000, null);
zk.register(new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
if (event.getType() == EventType.None
&& event.getPath() == null) {
connectedSignal.countDown();
} else if (event.getType() == EventType.NodeChildrenChanged) {
try {
System.out.println("NodeChildrenChanged.");
List<String> children = zk.getChildren(event.getPath(), true);
System.out.println("Children: " + children);
} catch (KeeperException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
});
connectedSignal.await(); zk.create("/zk-huey", "root".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
zk.create("/zk-huey/node1", "node1".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
zk.create("/zk-huey/node2", "node2".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT); Stat stat = new Stat();
List<String> children = zk.getChildren("/zk-huey",
true, // 注册默认的Watcher，当子节点类别发送变更的话，向客户端发送通知
stat // 用于描述节点状态信息
);
System.out.println("Stat: " + stat);
System.out.println("Children: " + children); zk.create("/zk-huey/node3", "node3".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT); Thread.sleep(10 * 1000);
zk.close();
} }
结果输出：
Stat: 4294967436,4294967436,1425201236879,1425201236879,0,2,0,0,4,2,4294967438 Children: [node2, node1]
NodeChildrenChanged.
State: CONNECTED
Children: [node2, node3, node1]
2. 使用异步API获取子节点列表
package com.huey.dream.demo; 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; /**
* 使用异步API获取子节点列表
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
final ZooKeeper zk = new ZooKeeper("192.168.1.109:2182", 5000, null);
zk.register(new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
if (event.getType() == EventType.None
&& event.getPath() == null) {
connectedSignal.countDown();
} else if (event.getType() == EventType.NodeChildrenChanged) {
try {
System.out.println("NodeChildrenChanged.");
List<String> children = zk.getChildren(event.getPath(), true);
System.out.println("Children: " + children);
} catch (KeeperException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
});
connectedSignal.await(); zk.create("/zk-huey", "root".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
zk.create("/zk-huey/node1", "node1".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
zk.create("/zk-huey/node2", "node2".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT); zk.getChildren("/zk-huey",
true,
new AsyncCallback.Children2Callback() {
@Override
public void processResult(int rc, String path, Object ctx,
List<String> children, Stat stat) {
System.out.println("ResultCode: " + rc);
System.out.println("ZNode: " + path);
System.out.println("Context: " + ctx);
System.out.println("Children: " + children);
System.out.println("Stat: " + stat);
}
},
"The Context"
); zk.create("/zk-huey/node3", "node3".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT); Thread.sleep(10 * 1000);
zk.close();
} }
五、获取节点数据内容
1. 使用同步API获取节点数据内容
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.CreateMode;
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; /**
* 使用同步API获取节点数据内容
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
final ZooKeeper zk = new ZooKeeper("192.168.1.109:2182", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
if (event.getType() == EventType.None
&& event.getPath() == null) {
connectedSignal.countDown();
}
}
}
});
connectedSignal.await(); zk.create("/zk-huey", "hello".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
byte[] nodeData = zk.getData("/zk-huey", false, null);
System.out.println("NodeData: " + new String(nodeData)); zk.close();
} }
2. 使用异步API获取节点数据内容
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.AsyncCallback;
import org.apache.zookeeper.CreateMode;
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; /**
* 使用异步API获取节点数据内容
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
final ZooKeeper zk = new ZooKeeper("192.168.1.109:2182", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
if (event.getType() == EventType.None
&& event.getPath() == null) {
connectedSignal.countDown();
}
}
}
});
connectedSignal.await(); zk.create("/zk-huey", "hello".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
zk.getData(
"/zk-huey",
false,
new AsyncCallback.DataCallback() {
@Override
public void processResult(int rc, String path, Object ctx, byte[] data,
Stat stat) {
System.out.println("ResultCode: " + rc);
System.out.println("ZNode: " + path);
System.out.println("Context: " + ctx);
System.out.println("NodeData: " + new String(data));
System.out.println("Stat: " + stat);
}
},
"The Context"
); zk.close();
} }
六、更新数据
1. 使用同步API更新节点数据内容
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.CreateMode;
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; /**
* 使用同步API更新节点数据内容
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
final ZooKeeper zk = new ZooKeeper("192.168.1.109:2182", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
if (event.getType() == EventType.None
&& event.getPath() == null) {
connectedSignal.countDown();
}
}
}
});
connectedSignal.await(); zk.create("/zk-huey", "hello".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
byte[] nodeData = zk.getData("/zk-huey", false, null);
System.out.println("NodeData: " + nodeData); zk.setData("/zk-huey", "world".getBytes(), -1);
nodeData = zk.getData("/zk-huey", false, null);
System.out.println("NodeData: " + nodeData); zk.close();
} }
2. 使用异步API更新节点数据内容
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.AsyncCallback;
import org.apache.zookeeper.CreateMode;
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; /**
* 使用异步API更新节点数据内容
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
final ZooKeeper zk = new ZooKeeper("192.168.1.109:2182", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
if (event.getType() == EventType.None
&& event.getPath() == null) {
connectedSignal.countDown();
}
}
}
});
connectedSignal.await(); zk.create("/zk-huey", "hello".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
byte[] nodeData = zk.getData("/zk-huey", false, null);
System.out.println("NodeData: " + nodeData); zk.setData(
"/zk-huey",
"world".getBytes(),
-1,
new AsyncCallback.StatCallback() {
@Override
public void processResult(int rc, String path, Object ctx, Stat stat) {
System.out.println("ResultCode: " + rc);
System.out.println("ZNode: " + path);
System.out.println("Context: " + ctx);
System.out.println("Stat: " + stat);
}
},
"The Context"
); zk.close();
} }
七、判断节点是否存在
1. 使用同步API判断节点是否存在
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.AsyncCallback;
import org.apache.zookeeper.CreateMode;
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; /**
* 使用同步API判断节点是否存在
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
final ZooKeeper zk = new ZooKeeper("192.168.1.109:2182", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
if (event.getType() == EventType.None
&& event.getPath() == null) {
connectedSignal.countDown();
}
}
}
});
connectedSignal.await(); Stat stat = zk.exists("/zk-huey", false);
if (stat == null) {
zk.create("/zk-huey", "hello".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
} else {
System.out.println("Stat: " + stat);
} zk.close();
} }
2. 使用异步API判断节点是否存在
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.AsyncCallback;
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.data.Stat; /**
* 使用异步API判断节点是否存在
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { final CountDownLatch connectedSignal = new CountDownLatch(1);
final ZooKeeper zk = new ZooKeeper("192.168.1.109:2182", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getState() == KeeperState.SyncConnected) {
if (event.getType() == EventType.None
&& event.getPath() == null) {
connectedSignal.countDown();
}
}
}
});
connectedSignal.await(); zk.exists(
"/zk-huey",
false,
new AsyncCallback.StatCallback() {
@Override
public void processResult(int rc, String path, Object ctx, Stat stat) {
System.out.println("ResultCode: " + rc);
System.out.println("ZNode: " + path);
System.out.println("Context: " + ctx);
System.out.println("Stat: " + stat);
}
},
"The Context"
); zk.close();
} }
八、权限控制
package com.huey.dream.demo; import java.util.concurrent.CountDownLatch; import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.ZooDefs.Ids; /**
* ZooKeeper权限控制
* @author huey
* @version 1.0
* @created 2015-3-1
*/
public class ZKDemo { public static void main(String[] args) throws Exception { /**
* 使用含有权限信息的zookeeper会话创建数据节点
*/
final CountDownLatch connectedSignal = new CountDownLatch(1);
ZooKeeper zk = new ZooKeeper("192.168.1.109:2182", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
connectedSignal.countDown();
}
});
connectedSignal.await();
zk.addAuthInfo("digest", "huey:123".getBytes());
zk.create("/zk-huey", "hello".getBytes(), Ids.CREATOR_ALL_ACL, CreateMode.PERSISTENT);
zk.close(); /**
* 使用无权限信息的zookeeper会话访问含有权限信息的数据节点
*/
try {
final CountDownLatch signal = new CountDownLatch(1);
ZooKeeper zk1 = new ZooKeeper("192.168.1.109:2182", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
signal.countDown();
}
});
signal.await();
zk1.getData("/zk-huey", false, null);
System.out.println("NodeData: " + new String(zk1.getData("/zk-huey", false, null)));
zk1.close();
} catch (Exception e) {
System.out.println("Failed to delete Znode: " + e.getMessage());
} /**
* 使用错误权限信息的zookeeper会话访问含有权限信息的数据节点
*/
try {
final CountDownLatch signal = new CountDownLatch(1);
ZooKeeper zk2 = new ZooKeeper("192.168.1.109:2182", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
signal.countDown();
}
});
signal.await();
zk2.addAuthInfo("digest", "huey:abc".getBytes());
System.out.println("NodeData: " + new String(zk2.getData("/zk-huey", false, null)));
zk2.close();
} catch (Exception e) {
System.out.println("Failed to delete Znode: " + e.getMessage());
} /**
* 使用正确权限信息的zookeeper会话访问含有权限信息的数据节点
*/
try {
final CountDownLatch signal = new CountDownLatch(1);
ZooKeeper zk3 = new ZooKeeper("192.168.1.109:2182", 5000, new Watcher() {
@Override
public void process(WatchedEvent event) {
signal.countDown();
}
});
signal.await();
zk3.addAuthInfo("digest", "huey:123".getBytes());
System.out.println("NodeData: " + new String(zk3.getData("/zk-huey", false, null)));
zk3.close();
} catch (Exception e) {
System.out.println("Failed to delete Znode: " + e.getMessage());
}
} }
结果输出：
Failed to delete Znode: KeeperErrorCode = NoAuth for /zk-huey
Failed to delete Znode: KeeperErrorCode = NoAuth for /zk-huey
NodeData: hello
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