ZooKeeper（三）ZooKeeper客户端命令和Java原

a, 显示根目录下文件：ls / 使用ls命令来查看当前ZooKeeper中所包含的内容
b, 显示根目录下文件：ls2 / 查看当前节点数据并能看到更新次数等数据
c, 创建文件并设置初始内容：create /zk "value" 创建一个新的znode节点"zk"以及与它关联的字符串。create -e 是临时节点，create -s 顺序节点
d, 获取文件内容：get /zk 确认znode是否包含我们所创建的字符串
e, 修改文件内容：set /zk "newValue" 对zk所关联的字符串进行设置
f, 删除文件：delete /zk 将刚创建的znode删除，如果存在子节点删除失败
g, 递归删除：rmr /zk 将刚才创建的znode删除，子节点同时删除
h, 退出客户端：quit
i, 帮助命令：help

 a, echo stat|nc 127.0.0.1 2181 来查看哪个节点被选择作为follower或者leader
 b, echo ruok|nc 127.0.0.1 2181 测试是否启动了该Sever,若回复imok表示已经启动
 c, echo dump|nc 127.0.0.1 2181 列出未经处理的会话和临时节点
 d, echo kill|nc 127.0.0.1 2181 关掉server
 e, echo conf|nc 127.0.0.1 2181 输出相关服务配置的详细信息
 f, echo cons|nc 127.0.0.1 2181 列出所有连接到服务器的客户端的完全的连接/会话的详细信息
 g, echo envi|nc 127.0.0.1 2181 输出关于服务环境详细信息（区别于conf命令）
 h, echo reqs|nc 127.0.0.1 2181 列出未经处理的请求
 i, echo wchs|nc 127.0.0.1 2181 列出服务器watch详细信息
 j, echo wchc|nc 127.0.0.1 2181 通过session列出服务器watch的详细信息，它的输出是一个与watch相关的会话的列表
 k, echo wchp|nc 127.0.0.1 2181 通过路径列出服务器watch的详细信息。它输出一个与session相关的路径

a, 没有专门的API去注册watcher,依附于增删改查API
b, watch是一次性产品
c, watch的process方法中，可对不同事件进行处理

a, 会话连接是异步的
b, Watch需要重复注册
c, Session重连机制
d, 开发复杂性较高

import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
/**
 * @Description: 连接zk
 * @Author: Jason.zhu
 * @Create: 2019/05/16 16:27
 */
public class ZKConnect implements Watcher {
  static org.slf4j.Logger logger = LoggerFactory.getLogger(ZKConnect.class);

  // 连接超时时间
  private static Integer timeout;

  // 连接地址
  private static String zkServerIp;

  static {
      Properties zkProperties = new Properties();
      InputStream is = ZKConnect.class.getResourceAsStream("/zk.properties");
      try {
          zkProperties.load(is);
      } catch (Exception e) {
          e.printStackTrace();
      }finally {
          try {
              if (is != null) {
                  is.close();
              }
          } catch (IOException e) {
              logger.error("关闭流失败", e);
          }
      }
      timeout = Integer.valueOf(zkProperties.getProperty("zk.timeout"));
      zkServerIp = zkProperties.getProperty("zk.zkServerIps");
  }

  @Override
  public void process(WatchedEvent watchedEvent) {
      logger.warn("触发了[" + watchedEvent.getType().name()+"]事件");
  }

  public static ZooKeeper getZooKeeper(){
      try {
          ZooKeeper zooKeeper = new ZooKeeper(zkServerIp, timeout, new ZKConnect());
          return zooKeeper;
      } catch (Exception e) {
          e.printStackTrace();
      }
      return null;
  }
}

import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.ZooDefs;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.ACL;
import org.apache.zookeeper.data.Id;
import org.apache.zookeeper.server.auth.DigestAuthenticationProvider;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.ArrayList;
import java.util.List;

/**
 * @Description:
 * @Author: Jason.zhu
 * @Create: 2019/05/16 16:19
 */
public class ProtoClientACL {
  static Logger logger = LoggerFactory.getLogger(ProtoClientACL.class);

  public static void main(String[] args) throws Exception{
      ZooKeeper zooKeeper = ZKConnect.getZooKeeper();

      String scheme = "digest";
      String  auth = DigestAuthenticationProvider.generateDigest("jason:jason123");
      System.out.println("auth" + auth);

      List<ACL> aclList = new ArrayList<>();
      Id user1 = new Id(scheme, auth);
      aclList.add(new ACL(ZooDefs.Perms.ALL, user1));
      String result = zooKeeper.create("/aclNode","acl data".getBytes(), aclList, CreateMode.PERSISTENT);
      if(null != result){
          System.out.println("节点:"+result+"创建成功");
      }

      /*List<ACL> acls = zooKeeper.getACL("/aclNode",null);
      for(ACL acl : acls){
          System.out.println();
          System.out.println("权限scheme id：" + acl.getId());
          System.out.println("权限位：" + acl.getPerms());
      }*/

      zooKeeper.addAuthInfo(scheme,"jason:jason123".getBytes());
      System.out.println(new String(zooKeeper.getData("/aclNode",true, null)));

      zooKeeper.delete("/aclNode", -1);

      zooKeeper.close();

  }
}

package net.lc7.proto;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.ZooDefs;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.ACL;
import org.apache.zookeeper.data.Id;
import org.apache.zookeeper.server.auth.DigestAuthenticationProvider;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.ArrayList;
import java.util.List;

/**
 * @Description:
 * @Author: Jason.zhu
 * @Create: 2019/05/16 16:19
 */
public class ProtoClientACL {
  static Logger logger = LoggerFactory.getLogger(ProtoClientACL.class);

  public static void main(String[] args) throws Exception{
      ZooKeeper zooKeeper = ZKConnect.getZooKeeper();

      String scheme = "digest";
      String  auth = DigestAuthenticationProvider.generateDigest("jason:jason123");
      System.out.println("auth" + auth);

      List<ACL> aclList = new ArrayList<>();
      Id user1 = new Id(scheme, auth);
      aclList.add(new ACL(ZooDefs.Perms.ALL, user1));
      String result = zooKeeper.create("/aclNode","acl data".getBytes(), aclList, CreateMode.PERSISTENT);
      if(null != result){
          System.out.println("节点:"+result+"创建成功");
      }

      /*List<ACL> acls = zooKeeper.getACL("/aclNode",null);
      for(ACL acl : acls){
          System.out.println();
          System.out.println("权限scheme id：" + acl.getId());
          System.out.println("权限位：" + acl.getPerms());
      }*/

      zooKeeper.addAuthInfo(scheme,"jason:jason123".getBytes());
      System.out.println(new String(zooKeeper.getData("/aclNode",true, null)));

      zooKeeper.delete("/aclNode", -1);

      zooKeeper.close();

  }
}