public class Demo2 {

public static void main(String[] args) {
    String connectString = "192.168.168.133:2181";
    int sessionTimeout = 500000;  // 會話時間。設置長一點，如果不夠長，則會connect loss
    try {
        // 建立zookeeper鏈接
        ZooKeeper zk = new ZooKeeper(connectString, sessionTimeout, new Watcher(){
            public void process(WatchedEvent event) {
                // 監控所有觸發的事件
                System.out.println("start do something");
                EventType type = event.getType();        // 事件類型。枚舉
                KeeperState state = event.getState();    // 狀態。 枚舉
 

// type.getIntValue();
switch (type) {
case None: // int值對應 -1
System.out.println("none 事件觸發");
break;
case NodeCreated: // int值對應 1
System.out.println("創建節點事件發生了");
break;
case NodeDeleted: // int值對應 2
System.out.println("刪除節點事件發生了");
break;
case NodeDataChanged: // int值對應 3
System.out.println("節點數據改變事件發生了");
break;
case NodeChildrenChanged: // int值對應 4
System.out.println("子節點改變事件發生了");
break;
default:
System.out.println("I do not know what operate you do");
break;
}
// state.getIntValue(); NoSyncConnected 1和Unknown-1
switch (state) {
case Disconnected: // 0
System.out.println("失去連接");
break;
case SyncConnected: // 3
System.out.println("異步鏈接");
break;
case Expired: // -112
System.out.println("超時過期");
break;
default:
break;
}

                System.out.println("end");
            }
        });
        System.out.println("zk創建成功");
        List<String> list = zk.getChildren("/", true); // 獲取所有節點
        if(list != null) {
            for(String s : list)
                System.out.println(s);
        }
        // 在/app5節點下創建child節點
        zk.create("/app7", "/app8的子節點數據".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT); // 會對數據持久化，服務下次啟動任然存在
        zk.create("/app8", "/app8的子節點數據".getBytes(), Ids.OPEN_ACL_UNSAFE, 
                CreateMode.PERSISTENT, new StringCallback(){
            public void processResult(int rc, String path, Object ctx, String name) {
                System.out.println("rc: " + rc);
                System.out.println("path: " + path);
                System.out.println("Object:" + ctx);
                System.out.println("name: " + name);
            }
        }, "ctx object");

    } catch (IOException e) {
        e.printStackTrace();
    } catch (KeeperException e) {
        e.printStackTrace();
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
}
 

}

zk每一次操縱都會被監控watcher記錄下來

出現這種報錯是由於創建節點的時候沒有創建父節點 /app1

java 學習筆記（四） java連接ZooKeeper