Zookeeper:Curator增删改查API
2021-03-04 00:26
标签：for dia void 更新 lis 策略 mes 回调 mamicode Curator n ?kyoor??āt?r: a keeper or custodian of a museum or other collection - A ZooKeeper Keeper. Apache Curator is a Java/JVM client library for Apache ZooKeeper, a distributed coordination service. It includes a highlevel API framework and utilities to make using Apache ZooKeeper much easier and more reliable. It also includes recipes for common use cases and extensions such as service discovery and a Java 8 asynchronous DSL. curator官网 maven依赖： 连接对象创建的代码 重连策略： RetryOneTime(int sleepMsBetweenRetry)：只重连一次 RetryNTimes(int n, int sleepMsBetweenRetries)：重连n次 RetryUntilElapsed(int maxElapsedTimeMs, int sleepMsBetweenRetries)：每sleepMsBetweenRetries毫秒重连一次，总等待时间超过maxElapsedTimeMs毫秒后停止重连 ExponentialBackoffRetry(int baseSleepTimeMs, int maxRetries)：重连maxRetries次，重连间隔基于baseSleepTimeMs计算 支持递归创建节点 异步方式创建（删除、更新、查询省略）： 删除包含子节点的节点 读取属性： Zookeeper:Curator增删改查API 标签：for dia void 更新 lis 策略 mes 回调 mamicode 原文地址：https://www.cnblogs.com/wwjj4811/p/12956935.html1.介绍
What is Curator?
2.连接对象创建
public static void main(String[] args) {
CuratorFramework ct = CuratorFrameworkFactory.builder()
//ip:端口
.connectString("192.168.10.132:2181,192.168.10.133:2181,192.168.10.135:2181")//连接集群
//超时时间
.sessionTimeoutMs(5000)
//连接断开5秒后，会进行一次重连
.retryPolicy(new RetryOneTime(5000))
//命名空间，该命名空间作为父节点
.namespace("ct").build();
//打开连接
ct.start();
//是否连接成功
System.out.println(ct.isStarted());
//关闭连接
ct.close();
}
计算公式如下：baseSleepTimeMs*Math.max(1,random.nextInt(1
3.创建节点
ct.create()
//节点类型
.withMode(CreateMode.PERSISTENT)
//节点权限
.withACL(ZooDefs.Ids.OPEN_ACL_UNSAFE)
//节点路径和数据
.forPath("/node1","node1".getBytes());
ct.create()
//父节点不存在则创建
.creatingParentsIfNeeded()
//节点类型
.withMode(CreateMode.PERSISTENT)
//节点权限
.withACL(ZooDefs.Ids.OPEN_ACL_UNSAFE)
//节点路径和数据
.forPath("/node2/node2","node2".getBytes());
ct.create()
//父节点不存在则创建
.creatingParentsIfNeeded()
//节点类型
.withMode(CreateMode.PERSISTENT)
//节点权限
.withACL(ZooDefs.Ids.OPEN_ACL_UNSAFE)
//异步回调
.inBackground(new BackgroundCallback() {
public void processResult(CuratorFramework client, CuratorEvent event) throws Exception {
System.out.println(event.getPath()+":"+event.getType());
}
})
//节点路径和数据
.forPath("node3","node3".getBytes());
4.更新节点
ct.setData().withVersion(-1).forPath("/node3","node33".getBytes());
5.删除节点
ct.delete().withVersion(-1).forPath("/node3");
//递归删除
ct.delete()
.deletingChildrenIfNeeded()
.withVersion(-1).forPath("/node2");
6.查询节点
//查询
byte[] bytes = ct.getData().forPath("/node1");
System.out.println(new String(bytes));
Stat stat = new Stat();
byte[] bytes = ct.getData()
.storingStatIn(stat).forPath("/node1");
System.out.println(new String(bytes));
System.out.println(stat);
7.查询子节点数据
// /ct/node1/node2
List
8.判断节点是否存在
//如果节点不存在，则返回值为null
Stat stat = ct.checkExists().forPath("/node11");