Zookeeper（三）-- JAVA原生API

1、前提

jar包：zookeeper-3.4.9.jar，slf4j-api-1.6.1.jar，slf4j-log4j12-1.6.1.jar，log4j-1.2.15.jar

2、Demo

package com.xbq.zookeeper;

import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.List;

import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooDefs;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.ACL;
import org.apache.zookeeper.data.Id;
import org.apache.zookeeper.server.auth.DigestAuthenticationProvider;

/** 
 * @ClassName: ZookeeperDemo
 * @Description: TODO zookeeper測試
 * @author xbq
 * @version 1.0
 */
public class ZookeeperDemo {

    private static final int SESSION_TIMEOUT = 3000;
    
    public static void main(String[] args) {
            Zookeeper zooKeeper = null;
        try {
            zooKeeper = new ZooKeeper("192.168.242.128:2183", SESSION_TIMEOUT, new Watcher() {
                @Override
                public void process(WatchedEvent event) {
                    System.out.println("觸發事件：" + event.getType());
                }
            });
            String path = "/node_xbq";
            String data = "TestxbqCoder";
            
            create(zooKeeper, path, data);
            
//            update(zooKeeper, path, data);
            
//            delete(zooKeeper, path);
            
//            aclOper(zooKeeper, path, data);
            
//            aclOper2(zooKeeper, path, data);
            
//            doWatch(zooKeeper, path, data);
            
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if(zooKeeper ! = null){
                try{
                    zooKeeper.close();
                }catch(Exception e){
                }
            }
        }
    }
    
    /**
     * @Title: create
     * @Description: TODO    增長操做
     * @param zooKeeper
     * @param path
     * @param data
     * @throws KeeperException
     * @throws InterruptedException
     * @return: void
     */
    public static void create(ZooKeeper zooKeeper, String path, String data) throws KeeperException, InterruptedException{
        if(zooKeeper.exists(path, false) == null){    // 若是不存在節點，就新建
            // 第三個參數是 權限，第四個參數 表明持久節點
            // 權限分類：OPEN_ACL_UNSAFE：對全部用戶開放    READ_ACL_UNSAFE：只讀   CREATOR_ALL_ACL： 建立者能夠作任何操做
            zooKeeper.create(path, data.getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
        }
        System.out.println(new String(zooKeeper.getData(path, true, null)));
    }
    
    /**
     * @Title: update
     * @Description: TODO 修改操做
     * @param zooKeeper
     * @return: void
     * @throws InterruptedException 
     * @throws KeeperException 
     */
    public static void update(ZooKeeper zooKeeper, String path, String data) throws KeeperException, InterruptedException { 
        zooKeeper.setData(path, data.getBytes(), -1);  // -1標識任何版本號 均可以
        System.out.println(new String(zooKeeper.getData(path, true, null)));
    }
    
    /**
     * @Title: delete
     * @Description: TODO 刪除
     * @param zooKeeper
     * @param path
     * @throws KeeperException
     * @throws InterruptedException
     * @return: void
     */
    public static void delete(ZooKeeper zooKeeper, String path) throws KeeperException, InterruptedException{
        if(zooKeeper.exists(path, false) != null){
            zooKeeper.delete(path, -1);
        }
        if(zooKeeper.exists(path, false) != null){
            System.out.println(new String(zooKeeper.getData(path, true, null)));
        }
    }
    
    /**
     * @Title: aclOper
     * @Description: TODO 權限測試    先建立一個只讀權限節點，而後更新該節點
     * @param zooKeeper
     * @param path
     * @param data
     * @throws KeeperException
     * @throws InterruptedException
     * @return: void
     */
    public static void aclOper(ZooKeeper zooKeeper, String path, String data) throws KeeperException, InterruptedException{
        // 首先建立一個只讀的節點。第三個參數 表明只讀權限
        zooKeeper.create(path, data.getBytes(), Ids.READ_ACL_UNSAFE,CreateMode.PERSISTENT);
        System.out.println(new String(zooKeeper.getData(path, true, null)));
        // 測試更新節點，由於增長的是 只讀的，因此應該是不能夠修改的。發現報錯：org.apache.zookeeper.KeeperException$NoAuthException: KeeperErrorCode = NoAuth for /node_xbq
        zooKeeper.setData(path, "testRead_ACL".getBytes(), -1);
        }
    
    /**
     * @Title: aclOper2
     * @Description: TODO  自定義權限驗證
        * 自定義schema權限類型:digest,world,auth,ip，這裏用 digest舉例
     * @param zooKeeper
     * @param path
     * @param data
     * @throws KeeperException
     * @throws InterruptedException
     * @throws NoSuchAlgorithmException
     * @return: void
     */
    public static void aclOper2(ZooKeeper zooKeeper, String path, String data) throws KeeperException, InterruptedException, NoSuchAlgorithmException{
        // 第一個參數是 全部的權限，第二個參數是 經過 用戶名和密碼 驗證
        ACL acl = new ACL(ZooDefs.Perms.ALL, new Id("digest", DigestAuthenticationProvider.generateDigest("root:root")));
        List<ACL> acls = new ArrayList<ACL>();
        acls.add(acl);
        
        if(zooKeeper.exists(path, false) == null){
            zooKeeper.create(path, data.getBytes(), acls, CreateMode.PERSISTENT);
        }
        
        zooKeeper.addAuthInfo("digest", "root:root".getBytes());
        
        // 經過下面的方式 是能夠取到值的，由於 加了 用戶名和 密碼 驗證 ，須要 加上  zooKeeper.addAuthInfo("digest", "root:root".getBytes());
        System.out.println(new String(zooKeeper.getData(path, true, null)));
    }
    
    /**
     * @Title: doWatch
     * @Description: TODO 監聽
     * @param zooKeeper
     * @param path
     * @param data
     * @throws KeeperException
     * @throws InterruptedException
     * @return: void
     */
    public static void doWatch(ZooKeeper zooKeeper, String path, String data) throws KeeperException, InterruptedException{
        if(zooKeeper.exists(path, false) == null){
            zooKeeper.create(path, data.getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
        }
        // 監聽 path節點
        zooKeeper.getData(path, new Watcher() {
            @Override
            public void process(WatchedEvent event) {
                System.out.println("觸發了節點變動事件：" + event.getType());
            }
        }, null);
        // 用更新操做觸發 監聽事件
        zooKeeper.setData(path, "updateTest".getBytes(), -1);
    }
}
複製代碼

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