Zookeeper 的增删改查demo代码
public class SimpleZkClient {
private static final String connectString = "mini1:2181,mini2:2181,mini3:2181";
private static final int sessionTimeout = 2000;
ZooKeeper zkClient = null;
@Before
public void init() throws Exception {
zkClient = new ZooKeeper(connectString, sessionTimeout, new Watcher() {
@Override
public void process(WatchedEvent event) {
// 收到事件通知后的回调函数（应该是我们自己的事件处理逻辑）
System.out.println(event.getType() + "---" + event.getPath());
try {
zkClient.getChildren("/", true);
} catch (Exception e) {
}
}
});
}
/**
* 数据的增删改查
*/
// 创建数据节点到zk中
public void testCreate() throws KeeperException, InterruptedException {
// 参数1：要创建的节点的路径 参数2：节点大数据 参数3：节点的权限 参数4：节点的类型
String nodeCreated = zkClient.create("/eclipse", "hellozk".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
//上传的数据可以是任何类型，但都要转成byte[]
}
//判断znode是否存在
@Test
public void testExist() throws Exception{
Stat stat = zkClient.exists("/eclipse", false);
System.out.println(stat==null?"not exist":"exist");
}
// 获取子节点
@Test
public void getChildren() throws Exception {
List<String> children = zkClient.getChildren("/", true);
for (String child : children) {
System.out.println(child);
}
Thread.sleep(Long.MAX_VALUE);
}
//获取znode的数据
@Test
public void getData() throws Exception {
byte[] data = zkClient.getData("/eclipse", false, null);
System.out.println(new String(data));
}
//删除znode
@Test
public void deleteZnode() throws Exception {
//参数2：指定要删除的版本，-1表示删除所有版本
zkClient.delete("/eclipse", -1);
}
//删除znode
@Test
public void setData() throws Exception {
zkClient.setData("/app1", "imissyou angelababy".getBytes(), -1);
byte[] data = zkClient.getData("/app1", false, null);
System.out.println(new String(data));
}
}