Apache ZooKeeper \u662f\u4e00\u4e2a\u5206\u5e03\u5f0f\u7684\u3001\u5f00\u653e\u6e90\u7801\u7684\u5206\u5e03\u5f0f\u5e94\u7528\u7a0b\u5e8f\u534f\u8c03\u670d\u52a1，\u662f Hadoop \u548c HBase \u7684\u91cd\u8981\u7ec4\u4ef6\u3002\u5b83\u4e3b\u8981\u7528\u4e8e\u89e3\u51b3\u5206\u5e03\u5f0f\u5e94\u7528\u4e2d\u7ecf\u5e38\u9047\u5230\u7684\u4e00\u4e9b\u6570\u636e\u7ba1\u7406\u95ee\u9898，\u5982\u7edf\u4e00\u547d\u540d\u670d\u52a1\u3001\u72b6\u6001\u540c\u6b65\u670d\u52a1\u3001\u96c6\u7fa4\u7ba1\u7406\u3001\u5206\u5e03\u5f0f\u5e94\u7528\u914d\u7f6e\u9879\u7684\u7ba1\u7406\u7b49\u3002<\/p>\n
ZooKeeper \u7684\u6570\u636e\u6a21\u578b\u91c7\u7528\u7c7b\u4f3c\u6587\u4ef6\u7cfb\u7edf\u7684\u6811\u72b6\u7ed3\u6784，\u6bcf\u4e2a\u8282\u70b9\u79f0\u4e3a\u4e00\u4e2a ZNode\u3002ZNode \u662f ZooKeeper \u4e2d\u6570\u636e\u5b58\u50a8\u7684\u57fa\u672c\u5355\u5143，\u53ef\u4ee5\u5b58\u50a8\u6570\u636e，\u4e5f\u53ef\u4ee5\u6709\u5b50\u8282\u70b9\u3002\u5bf9 ZNode \u7684\u521b\u5efa\u3001\u5220\u9664\u3001\u8bfb\u53d6\u548c\u66f4\u65b0\u64cd\u4f5c\u662f ZooKeeper \u5ba2\u6237\u7aef\u6700\u6838\u5fc3\u7684 API\u3002<\/p>\n
\u672c\u6587\u5c06\u91cd\u70b9\u4ecb\u7ecd\u5982\u4f55\u4f7f\u7528 ZooKeeper \u7684 Java API \u8fdb\u884c\u8282\u70b9\u7684\u521b\u5efa\u4e0e\u5220\u9664\u64cd\u4f5c，\u8fd9\u662f\u8fdb\u884c ZooKeeper \u5e94\u7528\u5f00\u53d1\u7684\u57fa\u7840\u3002<\/p>\n
\u9996\u5148，\u9700\u8981\u5728\u9879\u76ee\u4e2d\u5f15\u5165 ZooKeeper \u7684 Java \u5ba2\u6237\u7aef\u4f9d\u8d56\u3002\u4ee5 Maven \u9879\u76ee\u4e3a\u4f8b，\u5728 pom.xml \u4e2d\u6dfb\u52a0\u4ee5\u4e0b\u4f9d\u8d56：<\/p>\n
<dependency>
\n <groupId>org.apache.zookeeper<\/groupId>
\n <artifactId>zookeeper<\/artifactId>
\n <version>3.8.0<\/version>
\n<\/dependency><\/p>\n
\u5728\u5f00\u53d1\u4e4b\u524d，\u9700\u8981\u786e\u4fdd\u6709\u4e00\u4e2a\u53ef\u7528\u7684 ZooKeeper \u670d\u52a1\u3002\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u65b9\u5f0f\u4e4b\u4e00\u542f\u52a8：<\/p>\n
\u9ed8\u8ba4\u60c5\u51b5\u4e0b，ZooKeeper \u670d\u52a1\u4f1a\u5728 localhost:2181 \u7aef\u53e3\u76d1\u542c\u3002<\/p>\n
\u5728\u8fdb\u884c\u4efb\u4f55\u8282\u70b9\u64cd\u4f5c\u4e4b\u524d，\u9996\u5148\u9700\u8981\u5efa\u7acb\u4e0e ZooKeeper \u670d\u52a1\u5668\u7684\u8fde\u63a5\u3002ZooKeeper \u5ba2\u6237\u7aef\u901a\u8fc7 ZooKeeper \u7c7b\u6765\u521b\u5efa\u548c\u7ba1\u7406\u8fde\u63a5\u3002<\/p>\n
import org.apache.zookeeper.WatchedEvent;
\nimport org.apache.zookeeper.Watcher;
\nimport org.apache.zookeeper.ZooKeeper;
\nimport java.io.IOException;
\nimport java.util.concurrent.CountDownLatch;<\/p>\n
public class ZkClientDemo {
\n private static final String CONNECT_STRING = "localhost:2181";
\n private static final int SESSION_TIMEOUT = 5000; \/\/ \u4f1a\u8bdd\u8d85\u65f6\u65f6\u95f4，\u5355\u4f4d\u6beb\u79d2<\/p>\n
public static ZooKeeper getConnection() throws IOException, InterruptedException {
\n CountDownLatch connectedLatch = new CountDownLatch(1);
\n \/\/ \u521b\u5efa ZooKeeper \u5b9e\u4f8b，\u5f02\u6b65\u8fde\u63a5
\n ZooKeeper zk = new ZooKeeper(CONNECT_STRING, SESSION_TIMEOUT, new Watcher() {
\n @Override
\n public void process(WatchedEvent event) {
\n if (event.getState() == Event.KeeperState.SyncConnected) {
\n \/\/ \u8fde\u63a5\u5efa\u7acb\u6210\u529f
\n connectedLatch.countDown();
\n }
\n }
\n });
\n \/\/ \u7b49\u5f85\u8fde\u63a5\u5efa\u7acb\u5b8c\u6210
\n connectedLatch.await();
\n System.out.println("ZooKeeper \u8fde\u63a5\u5efa\u7acb\u6210\u529f！");
\n return zk;
\n }
\n}<\/p>\n
\u5173\u952e\u53c2\u6570\u8bf4\u660e：<\/p>\n
ZooKeeper \u63d0\u4f9b\u4e86 create \u65b9\u6cd5\u6765\u521b\u5efa\u8282\u70b9\u3002\u521b\u5efa\u8282\u70b9\u65f6\u9700\u8981\u6307\u5b9a\u8def\u5f84\u3001\u6570\u636e\u3001ACL（\u8bbf\u95ee\u63a7\u5236\u5217\u8868）\u548c\u8282\u70b9\u7c7b\u578b\u3002<\/p>\n
ZooKeeper \u652f\u6301\u4ee5\u4e0b\u51e0\u79cd\u8282\u70b9\u7c7b\u578b：<\/p>\n
import org.apache.zookeeper.CreateMode;
\nimport org.apache.zookeeper.ZooDefs;
\nimport org.apache.zookeeper.data.ACL;
\nimport java.util.List;<\/p>\n
public class ZkCreateDemo {
\n public static void createPersistentNode(ZooKeeper zk, String path, String data) throws Exception {
\n \/\/ \u9ed8\u8ba4\u4f7f\u7528 OPEN_ACL_UNSAFE（\u6240\u6709\u4eba\u62e5\u6709\u6240\u6709\u6743\u9650）
\n List<ACL> acl = ZooDefs.Ids.OPEN_ACL_UNSAFE;
\n \/\/ \u521b\u5efa\u6301\u4e45\u8282\u70b9
\n String createdPath = zk.create(path,
\n data.getBytes(),
\n acl,
\n CreateMode.PERSISTENT);
\n System.out.println("\u6301\u4e45\u8282\u70b9\u521b\u5efa\u6210\u529f，\u8def\u5f84: " + createdPath);
\n }<\/p>\n
public static void main(String[] args) throws Exception {
\n ZooKeeper zk = ZkClientDemo.getConnection();
\n \/\/ \u521b\u5efa \/demo \u8282\u70b9，\u6570\u636e\u4e3a "hello zookeeper"
\n createPersistentNode(zk, "\/demo", "hello zookeeper");
\n zk.close();
\n }
\n}<\/p>\n
public class ZkCreateEphemeralDemo {
\n public static void createEphemeralNode(ZooKeeper zk, String path, String data) throws Exception {
\n String createdPath = zk.create(path,
\n data.getBytes(),
\n ZooDefs.Ids.OPEN_ACL_UNSAFE,
\n CreateMode.EPHEMERAL);
\n System.out.println("\u4e34\u65f6\u8282\u70b9\u521b\u5efa\u6210\u529f，\u8def\u5f84: " + createdPath);
\n \/\/ \u4e34\u65f6\u8282\u70b9\u4f1a\u5728\u4f1a\u8bdd\u7ed3\u675f\u540e\u81ea\u52a8\u5220\u9664
\n }<\/p>\n
public static void main(String[] args) throws Exception {
\n ZooKeeper zk = ZkClientDemo.getConnection();
\n createEphemeralNode(zk, "\/tempNode", "\u4e34\u65f6\u6570\u636e");
\n \/\/ \u4fdd\u6301\u8fde\u63a5，\u89c2\u5bdf\u8282\u70b9\u5b58\u5728
\n Thread.sleep(10000);
\n zk.close(); \/\/ \u5173\u95ed\u8fde\u63a5\u540e，\u4e34\u65f6\u8282\u70b9\u4f1a\u88ab\u81ea\u52a8\u5220\u9664
\n }
\n}<\/p>\n
public class ZkCreateSequentialDemo {
\n public static void createSequentialNode(ZooKeeper zk, String path, String data) throws Exception {
\n \/\/ \u521b\u5efa\u6301\u4e45\u987a\u5e8f\u8282\u70b9
\n String createdPath = zk.create(path,
\n data.getBytes(),
\n ZooDefs.Ids.OPEN_ACL_UNSAFE,
\n CreateMode.PERSISTENT_SEQUENTIAL);
\n System.out.println("\u987a\u5e8f\u8282\u70b9\u521b\u5efa\u6210\u529f，\u5b9e\u9645\u8def\u5f84: " + createdPath);
\n \/\/ \u5982\u679c path \u662f "\/seq-"，\u5b9e\u9645\u521b\u5efa\u7684\u8def\u5f84\u53ef\u80fd\u662f "\/seq-0000000001"
\n }<\/p>\n
public static void main(String[] args) throws Exception {
\n ZooKeeper zk = ZkClientDemo.getConnection();
\n \/\/ \u8fde\u7eed\u521b\u5efa\u4e09\u4e2a\u987a\u5e8f\u8282\u70b9
\n createSequentialNode(zk, "\/seq-", "data1");
\n createSequentialNode(zk, "\/seq-", "data2");
\n createSequentialNode(zk, "\/seq-", "data3");
\n zk.close();
\n }
\n}<\/p>\n
ZooKeeper \u63d0\u4f9b\u4e86 delete \u65b9\u6cd5\u6765\u5220\u9664\u8282\u70b9\u3002\u5220\u9664\u8282\u70b9\u65f6\u9700\u8981\u6ce8\u610f：<\/p>\n
import org.apache.zookeeper.KeeperException;<\/p>\n
public class ZkDeleteDemo {
\n public static void deleteNode(ZooKeeper zk, String path) throws Exception {
\n try {
\n \/\/ version = -1 \u8868\u793a\u5ffd\u7565\u7248\u672c\u53f7，\u76f4\u63a5\u5220\u9664
\n zk.delete(path, -1);
\n System.out.println("\u8282\u70b9\u5220\u9664\u6210\u529f: " + path);
\n } catch (KeeperException.NoNodeException e) {
\n System.out.println("\u8282\u70b9\u4e0d\u5b58\u5728: " + path);
\n } catch (KeeperException.NotEmptyException e) {
\n System.out.println("\u8282\u70b9 " + path + " \u4e0b\u5b58\u5728\u5b50\u8282\u70b9，\u65e0\u6cd5\u5220\u9664");
\n }
\n }<\/p>\n
public static void main(String[] args) throws Exception {
\n ZooKeeper zk = ZkClientDemo.getConnection();<\/p>\n
\/\/ \u5148\u521b\u5efa\u4e00\u4e2a\u6d4b\u8bd5\u8282\u70b9
\n zk.create("\/testDelete", "to be deleted".getBytes(),
\n ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);<\/p>\n
\/\/ \u5220\u9664\u8be5\u8282\u70b9
\n deleteNode(zk, "\/testDelete");<\/p>\n
zk.close();
\n }
\n}<\/p>\n
ZooKeeper \u4e2d\u6bcf\u4e2a\u8282\u70b9\u90fd\u6709\u4e00\u4e2a\u6570\u636e\u7248\u672c\u53f7（version），\u6bcf\u6b21\u6570\u636e\u66f4\u65b0\u7248\u672c\u53f7\u90fd\u4f1a\u9012\u589e\u3002\u5220\u9664\u65f6\u53ef\u4ee5\u6307\u5b9a\u7248\u672c\u53f7，\u53ea\u6709\u5f53\u524d\u7248\u672c\u53f7\u5339\u914d\u65f6\u624d\u4f1a\u6267\u884c\u5220\u9664，\u8fd9\u5b9e\u73b0\u4e86\u4e50\u89c2\u9501\u673a\u5236\u3002<\/p>\n
public class ZkDeleteWithVersionDemo {
\n public static void deleteNodeWithVersion(ZooKeeper zk, String path, int expectedVersion) throws Exception {
\n try {
\n zk.delete(path, expectedVersion);
\n System.out.println("\u8282\u70b9\u5220\u9664\u6210\u529f: " + path + " (\u7248\u672c: " + expectedVersion + ")");
\n } catch (KeeperException.BadVersionException e) {
\n System.out.println("\u7248\u672c\u4e0d\u5339\u914d，\u5220\u9664\u5931\u8d25\u3002\u5f53\u524d\u7248\u672c\u53ef\u80fd\u5df2\u88ab\u5176\u4ed6\u5ba2\u6237\u7aef\u4fee\u6539\u3002");
\n }
\n }<\/p>\n
public static void main(String[] args) throws Exception {
\n ZooKeeper zk = ZkClientDemo.getConnection();<\/p>\n
\/\/ \u521b\u5efa\u8282\u70b9\u5e76\u83b7\u53d6\u5176\u5f53\u524d\u72b6\u6001（\u5305\u542b\u7248\u672c\u53f7）
\n zk.create("\/casNode", "initial".getBytes(),
\n ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);<\/p>\n
\/\/ \u83b7\u53d6\u8282\u70b9\u72b6\u6001，\u5f97\u5230\u5f53\u524d\u7248\u672c\u53f7
\n org.apache.zookeeper.data.Stat stat = zk.exists("\/casNode", false);
\n int currentVersion = stat.getVersion();
\n System.out.println("\u5f53\u524d\u8282\u70b9\u7248\u672c: " + currentVersion);<\/p>\n
\/\/ \u4f7f\u7528\u6b63\u786e\u7248\u672c\u53f7\u5220\u9664（\u5e94\u8be5\u6210\u529f）
\n deleteNodeWithVersion(zk, "\/casNode", currentVersion);<\/p>\n
\/\/ \u5c1d\u8bd5\u4f7f\u7528\u9519\u8bef\u7248\u672c\u53f7\u5220\u9664（\u5e94\u8be5\u5931\u8d25）
\n \/\/ deleteNodeWithVersion(zk, "\/casNode", currentVersion); \/\/ \u8282\u70b9\u5df2\u4e0d\u5b58\u5728<\/p>\n
zk.close();
\n }
\n}<\/p>\n
ZooKeeper \u539f\u751f\u7684 delete \u65b9\u6cd5\u4e0d\u80fd\u5220\u9664\u542b\u6709\u5b50\u8282\u70b9\u7684\u8282\u70b9\u3002\u5982\u679c\u9700\u8981\u5220\u9664\u6574\u4e2a\u5b50\u6811，\u9700\u8981\u5148\u9012\u5f52\u5220\u9664\u6240\u6709\u5b50\u8282\u70b9\u3002<\/p>\n
import java.util.List;<\/p>\n
public class ZkDeleteRecursiveDemo {
\n public static void deleteRecursive(ZooKeeper zk, String path) throws Exception {
\n \/\/ \u83b7\u53d6\u5b50\u8282\u70b9\u5217\u8868
\n List<String> children = zk.getChildren(path, false);
\n for (String child : children) {
\n String childPath = path.equals("\/") ? "\/" + child : path + "\/" + child;
\n deleteRecursive(zk, childPath); \/\/ \u9012\u5f52\u5220\u9664\u5b50\u8282\u70b9
\n }
\n \/\/ \u5220\u9664\u5f53\u524d\u8282\u70b9
\n try {
\n zk.delete(path, -1);
\n System.out.println("\u5220\u9664\u8282\u70b9: " + path);
\n } catch (KeeperException.NoNodeException e) {
\n \/\/ \u8282\u70b9\u53ef\u80fd\u5df2\u88ab\u5220\u9664，\u5ffd\u7565
\n }
\n }<\/p>\n
public static void main(String[] args) throws Exception {
\n ZooKeeper zk = ZkClientDemo.getConnection();<\/p>\n
\/\/ \u521b\u5efa\u6d4b\u8bd5\u6811\u7ed3\u6784
\n zk.create("\/parent", "parent data".getBytes(),
\n ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
\n zk.create("\/parent\/child1", "child1".getBytes(),
\n ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
\n zk.create("\/parent\/child2", "child2".getBytes(),
\n ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
\n zk.create("\/parent\/child1\/grandchild", "grand".getBytes(),
\n ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);<\/p>\n
\/\/ \u9012\u5f52\u5220\u9664\u6574\u4e2a \/parent \u5b50\u6811
\n deleteRecursive(zk, "\/parent");<\/p>\n
zk.close();
\n }
\n}<\/p>\n
\u4e0b\u9762\u662f\u4e00\u4e2a\u6574\u5408\u4e86\u521b\u5efa\u548c\u5220\u9664\u529f\u80fd\u7684\u5de5\u5177\u7c7b，\u5305\u542b\u5f02\u5e38\u5904\u7406\u548c\u8fde\u63a5\u7ba1\u7406\u3002<\/p>\n
import org.apache.zookeeper.*;
\nimport org.apache.zookeeper.data.ACL;
\nimport org.apache.zookeeper.data.Stat;
\nimport java.io.IOException;
\nimport java.util.List;
\nimport java.util.concurrent.CountDownLatch;<\/p>\n
public class ZkNodeManager {
\n private ZooKeeper zk;
\n private final String connectString;
\n private final int sessionTimeout;<\/p>\n
public ZkNodeManager(String connectString, int sessionTimeout) {
\n this.connectString = connectString;
\n this.sessionTimeout = sessionTimeout;
\n }<\/p>\n
\/\/ \u5efa\u7acb\u8fde\u63a5
\n public void connect() throws IOException, InterruptedException {
\n CountDownLatch latch = new CountDownLatch(1);
\n this.zk = new ZooKeeper(connectString, sessionTimeout, event -> {
\n if (event.getState() == Watcher.Event.KeeperState.SyncConnected) {
\n latch.countDown();
\n }
\n });
\n latch.await();
\n System.out.println("Connected to ZooKeeper: " + connectString);
\n }<\/p>\n
\/\/ \u5173\u95ed\u8fde\u63a5
\n public void close() throws InterruptedException {
\n if (zk != null) {
\n zk.close();
\n System.out.println("ZooKeeper connection closed.");
\n }
\n }<\/p>\n
\/\/ \u521b\u5efa\u8282\u70b9
\n public String createNode(String path, String data, CreateMode mode) throws KeeperException, InterruptedException {
\n return createNode(path, data.getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, mode);
\n }<\/p>\n
public String createNode(String path, byte[] data, List<ACL> acl, CreateMode mode)
\n throws KeeperException, InterruptedException {
\n return zk.create(path, data, acl, mode);
\n }<\/p>\n
\/\/ \u5220\u9664\u8282\u70b9
\n public boolean deleteNode(String path) throws KeeperException, InterruptedException {
\n return deleteNode(path, -1);
\n }<\/p>\n
public boolean deleteNode(String path, int version) throws KeeperException, InterruptedException {
\n try {
\n zk.delete(path, version);
\n return true;
\n } catch (KeeperException.NoNodeException e) {
\n System.out.println("Node does not exist: " + path);
\n return false;
\n } catch (KeeperException.NotEmptyException e) {
\n System.out.println("Node has children, cannot delete: " + path);
\n return false;
\n } catch (KeeperException.BadVersionException e) {
\n System.out.println("Version mismatch for node: " + path);
\n return false;
\n }
\n }<\/p>\n
\/\/ \u9012\u5f52\u5220\u9664\u8282\u70b9\u53ca\u5176\u5b50\u8282\u70b9
\n public void deleteRecursive(String path) throws KeeperException, InterruptedException {
\n List<String> children = zk.getChildren(path, false);
\n for (String child : children) {
\n String childPath = path.equals("\/") ? "\/" + child : path + "\/" + child;
\n deleteRecursive(childPath);
\n }
\n deleteNode(path);
\n }<\/p>\n
\/\/ \u68c0\u67e5\u8282\u70b9\u662f\u5426\u5b58\u5728
\n public boolean exists(String path) throws KeeperException, InterruptedException {
\n Stat stat = zk.exists(path, false);
\n return stat != null;
\n }<\/p>\n
\/\/ \u4f7f\u7528\u793a\u4f8b
\n public static void main(String[] args) throws Exception {
\n ZkNodeManager manager = new ZkNodeManager("localhost:2181", 5000);
\n manager.connect();<\/p>\n
\/\/ \u521b\u5efa\u6301\u4e45\u8282\u70b9
\n String nodePath = manager.createNode("\/demoRoot", "root data", CreateMode.PERSISTENT);
\n System.out.println("Created: " + nodePath);<\/p>\n
\/\/ \u521b\u5efa\u5b50\u8282\u70b9
\n manager.createNode("\/demoRoot\/child1", "child data", CreateMode.PERSISTENT);<\/p>\n
\/\/ \u68c0\u67e5\u8282\u70b9\u662f\u5426\u5b58\u5728
\n System.out.println("\/demoRoot exists: " + manager.exists("\/demoRoot"));<\/p>\n
\/\/ \u5220\u9664\u5b50\u8282\u70b9
\n boolean deleted = manager.deleteNode("\/demoRoot\/child1");
\n System.out.println("Child deleted: " + deleted);<\/p>\n
\/\/ \u9012\u5f52\u5220\u9664\u7236\u8282\u70b9
\n manager.deleteRecursive("\/demoRoot");<\/p>\n
manager.close();
\n }
\n}<\/p>\n
1. \u5f15\u8a00Apache ZooKeeper \u662f\u4e00\u4e2a\u5206\u5e03\u5f0f\u7684\u3001\u5f00\u653e\u6e90\u7801\u7684\u5206\u5e03\u5f0f\u5e94\u7528\u7a0b\u5e8f\u534f\u8c03\u670d\u52a1，\u662f Hadoop \u548c HBase \u7684\u91cd\u8981\u7ec4\u4ef6\u3002\u5b83\u4e3b\u8981\u7528\u4e8e\u89e3\u51b3\u5206\u5e03\u5f0f\u5e94\u7528\u4e2d\u7ecf\u5e38\u9047\u5230\u7684\u4e00\u4e9b\u6570\u636e\u7ba1\u7406\u95ee\u9898，\u5982\u7edf\u4e00\u547d\u540d\u670d\u52a1\u3001\u72b6\u6001\u540c\u6b65\u670d\u52a1\u3001\u96c6\u7fa4\u7ba1\u7406\u3001\u5206\u5e03\u5f0f\u5e94\u7528\u914d\u7f6e\u9879\u7684\u7ba1\u7406\u7b49\u3002ZooKeeper \u7684\u6570\u636e\u6a21\u578b\u91c7\u7528\u7c7b\u4f3c\u6587\u4ef6\u7cfb\u7edf\u7684\u6811\u72b6\u7ed3\u6784，\u6bcf\u4e2a\u8282\u70b9\u79f0\u4e3a\u4e00\u4e2a ZNode\u3002ZNode \u662f ZooKeeper \u4e2d\u6570\u636e\u5b58\u50a8\u7684\u57fa\u672c\u5355\u5143，\u53ef\u4ee5\u5b58\u50a8\u6570\u636e&#x<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[99,1115,1898],"topic":[],"class_list":["post-95031","post","type-post","status-publish","format-standard","hentry","category-server","tag-java","tag-java-zookeeper","tag-zookeeper"],"yoast_head":"\n