zhangxiaocc 2019-11-07
依赖:
<dependency> <groupId>org.apache.zookeeper</groupId> <artifactId>zookeeper</artifactId> <version>3.4.6</version> </dependency>
代码:
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.KeeperState; import org.apache.zookeeper.ZooDefs.Ids; import org.apache.zookeeper.ZooKeeper; import org.apache.zookeeper.data.Stat; public class BaseZookeeper implements Watcher { private ZooKeeper zookeeper; /** * * 超时时间 * */ private static final int SESSION_TIME_OUT = 2000; private CountDownLatch countDownLatch = new CountDownLatch(1); @Override public void process(WatchedEvent event) { if (event.getState() == KeeperState.SyncConnected) { System.out.println("Watch received event"); countDownLatch.countDown(); } } /** * 连接zookeeper * * @param host * * @throws Exception * */ public void connectZookeeper(String host) throws Exception { zookeeper = new ZooKeeper(host, SESSION_TIME_OUT, this); countDownLatch.await(); System.out.println("zookeeper connection success"); } /** * * 创建节点 * * @param path * * @param data * * @throws Exception * */ public String createNode(String path, String data) throws Exception { return this.zookeeper.create(path, data.getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT); } /** * * 获取路径下所有子节点 * * @param path * * @return * * @throws KeeperException * * @throws InterruptedException * */ public List<String> getChildren(String path) throws KeeperException, InterruptedException { List<String> children = zookeeper.getChildren(path, false); return children; } /** * * 获取节点上面的数据 * * @param path 路径 * * @return * * @throws KeeperException * * @throws InterruptedException * */ public String getData(String path) throws KeeperException, InterruptedException { byte[] data = zookeeper.getData(path, false, null); if (data == null) { return ""; } return new String(data); } /** * * 设置节点信息 * * @param path 路径 * * @param data 数据 * * @return * * @throws KeeperException * * @throws InterruptedException * */ public Stat setData(String path, String data) throws KeeperException, InterruptedException { Stat stat = zookeeper.setData(path, data.getBytes(), -1); return stat; } public void updateNode(String path, String data) throws KeeperException, InterruptedException { zookeeper.setData(path, data.getBytes(), -1); } /** * * 删除节点 * * @param path * * @throws InterruptedException * * @throws KeeperException * */ public void deleteNode(String path) throws InterruptedException, KeeperException { zookeeper.delete(path, -1); } /** * * 获取创建时间 * * @param path * * @return * * @throws KeeperException * * @throws InterruptedException * */ public String getCTime(String path) throws KeeperException, InterruptedException { Stat stat = zookeeper.exists(path, false); return String.valueOf(stat.getCtime()); } /** * * 获取某个路径下孩子的数量 * * @param path * * @return * * @throws KeeperException * * @throws InterruptedException * */ public Integer getChildrenNum(String path) throws KeeperException, InterruptedException { int childenNum = zookeeper.getChildren(path, false).size(); return childenNum; } /** * * 关闭连接 * * @throws InterruptedException * */ public void closeConnection() throws InterruptedException { if (zookeeper != null) { zookeeper.close(); } } public static void main(String[] args) { BaseZookeeper zookeeper = new BaseZookeeper(); try { zookeeper.connectZookeeper("127.0.0.1:2181"); List<String> children = zookeeper.getChildren("/"); System.out.println(children); } catch (Exception e) { e.printStackTrace(); } } }