import org.apache.zookeeper.*;
public class ZooKeeperExample {
private static final int SESSION_TIMEOUT = 3000;
private ZooKeeper zooKeeper;
public void connect(String hosts) throws IOException, InterruptedException {
CountDownLatch connectedSignal = new CountDownLatch(1);
zooKeeper = new ZooKeeper(hosts, SESSION_TIMEOUT, event -> {
if (event.getState() == Watcher.Event.KeeperState.SyncConnected) {
connectedSignal.countDown();
}
});
connectedSignal.await();
}
public void createNode(String path, byte[] data) throws KeeperException, InterruptedException {
zooKeeper.create(path, data, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
}
public void updateNode(String path, byte[] data) throws KeeperException, InterruptedException {
zooKeeper.setData(path, data, zooKeeper.exists(path, true).getVersion());
}
public void deleteNode(String path) throws KeeperException, InterruptedException {
zooKeeper.delete(path, zooKeeper.exists(path, true).getVersion());
}
public byte[] getNodeData(String path) throws KeeperException, InterruptedException {
return zooKeeper.getData(path, false, null);
}
public void closeConnection() throws InterruptedException {
zooKeeper.close();
}
public static void main(String[] args) {
String hosts = "localhost:2181";
String path = "/example";
byte[] data = "Hello, ZooKeeper!".getBytes();
try {
ZooKeeperExample example = new ZooKeeperExample();
example.connect(hosts);
example.createNode(path, data);
byte[] nodeData = example.getNodeData(path);
System.out.println("Node data: " + new String(nodeData));
example.updateNode(path, "Hello, New ZooKeeper!".getBytes());
byte[] updatedNodeData = example.getNodeData(path);
System.out.println("Updated node data: " + new String(updatedNodeData));
example.deleteNode(path);
example.closeConnection();
e.printStackTrace();
}
}
}
