Java Code Examples for org.apache.zookeeper.Watcher.Event.KeeperState#SyncConnected

public ZooKeeper connect(String host) throws IOException, InterruptedException {
  zoo =
      new ZooKeeper(
          host,
          2000,
          new Watcher() {
            public void process(WatchedEvent we) {
              if (we.getState() == KeeperState.SyncConnected) {
                connectionLatch.countDown();
              }
            }
          });

  connectionLatch.await();
  return zoo;
}
 

@Override
public void process(WatchedEvent event) {
	//如果ZooKeeper连接处于正常连接状态
	if (event.getState() == KeeperState.SyncConnected) {
		//对于事件类型
		switch (event.getType()) {
		// 服务器节点更新
		case NodeChildrenChanged:
			try {
				//如果服务节点更新，则主动拉取服务列表
				getServerList();
			} catch (Exception e) {
				e.printStackTrace();
			}
			break;
		// 服务被删除了，则将整个监视器关闭，使得其失活
		case NodeDeleted:
			close();
			break;
		default:
			break;
		}
	}

}
 

public ZKTestEnv(Path path) throws Exception {
    zkServer = new TestingServer(1282, path.toFile(), true);
    // waiting for ZK to be reachable
    CountDownLatch latch = new CountDownLatch(1);
    ZooKeeper zk = new ZooKeeper(zkServer.getConnectString(),
            herddb.server.ServerConfiguration.PROPERTY_ZOOKEEPER_SESSIONTIMEOUT_DEFAULT, (WatchedEvent event) -> {
                LOG.log(Level.INFO, "ZK EVENT {0}", event);
                if (event.getState() == KeeperState.SyncConnected) {
                    latch.countDown();
                }
            });
    try {
        if (!latch.await(herddb.server.ServerConfiguration.PROPERTY_ZOOKEEPER_SESSIONTIMEOUT_DEFAULT, TimeUnit.MILLISECONDS)) {
            LOG.log(Level.INFO, "ZK client did not connect withing {0} seconds, maybe the server did not start up",
                    herddb.server.ServerConfiguration.PROPERTY_ZOOKEEPER_SESSIONTIMEOUT_DEFAULT);
        }
    } finally {
        zk.close(1000);
    }
    this.path = path;
}
 

private void expireZooKeeperSession(ZooKeeper zk, int timeout)
        throws IOException, InterruptedException, KeeperException {
    final CountDownLatch latch = new CountDownLatch(1);

    ZooKeeper newZk = new ZooKeeper(zkServers, timeout, new Watcher() {
        @Override
        public void process(WatchedEvent event) {
            if (event.getType() == EventType.None && event.getState() == KeeperState.SyncConnected) {
                latch.countDown();
            }
        }},
        zk.getSessionId(),
        zk.getSessionPasswd());

    if (!latch.await(timeout, TimeUnit.MILLISECONDS)) {
        throw KeeperException.create(KeeperException.Code.CONNECTIONLOSS);
    }

    newZk.close();
}
 

@Override
public boolean isLeader(){
    if (client.getCurrentState() == KeeperState.SyncConnected ){
        if(lock.getParticipantNodes().size()>0){
            return id.equals(client.getData(leaderPath+"/"+lock.getParticipantNodes().get(0)));
        }
    }
    
    return false;
}
 

private void sessionEvent(CountDownLatch connectionLatch, WatchedEvent event) {
  if (event.getState() == KeeperState.SyncConnected) {
    LOG.info("收到ZK连接成功事件！");
    connectionLatch.countDown();
  } else if (event.getState() == KeeperState.Expired) {
    LOG.error("会话超时，等待重新建立ZK连接...");
    try {
      reConnection();
    } catch (Exception e) {
      LOG.error(e.getMessage(), e);
    }
  } // Disconnected：Zookeeper会自动处理Disconnected状态重连
}
 

@Override
synchronized public void process(WatchedEvent event) {
    if (event.getState() == KeeperState.SyncConnected ||
        event.getState() == KeeperState.ConnectedReadOnly) {
        connected = true;
        notifyAll();
        clientConnected.countDown();
    } else {
        connected = false;
        notifyAll();
    }
}
 

private void sessionEvent(CountDownLatch connectionLatch, WatchedEvent event) {
    if (event.getState() == KeeperState.SyncConnected) {
        log.info("收到ZK连接成功事件！");
        connectionLatch.countDown();
    } else if (event.getState() == KeeperState.Expired) {
        log.error("会话超时，等待重新建立ZK连接...");
        try {
            reConnection();
        } catch (Exception e) {
            log.error(e.getMessage(),e);
        }
    } // Disconnected：Zookeeper会自动处理Disconnected状态重连
}
 

@Override
public void process(WatchedEvent event) {
    if (stopped) {
        return;
    }

    if (event.getType() == EventType.None &&
            (event.getState().equals(Event.KeeperState.Disconnected) ||
            event.getState().equals(Event.KeeperState.Expired))) {

        if (elected) {
            elected = false;
            log.info("No longer leader for the position of " + position);
            leaderProvisioner.setRequiredState(LeaderState.I_AM_NOT_LEADER);
        }

        // Note that if we get a disconnected event here, our watcher is not unregistered, thus we will
        // get a connected event on this watcher once we are reconnected.

        // Since we are not owner of the ZooKeeper handle, we assume Expired states are handled
        // elsewhere in the application.

    } else if (event.getType() == EventType.None && event.getState() == KeeperState.SyncConnected) {
        // Upon reconnect, since our session was not expired, our ephemeral node will still
        // exist (it might even be the leader), therefore have a look at the leaders.
        watchLeaders();
    }
}
 

@Override
synchronized public void process(WatchedEvent event) {
    if (event.getState() == KeeperState.SyncConnected ||
        event.getState() == KeeperState.ConnectedReadOnly) {
        connected = true;
        notifyAll();
        clientConnected.countDown();
    } else {
        connected = false;
        notifyAll();
    }
}
 

@Override
public void process(WatchedEvent event) { // Watcher interface

    if (event.getState() == KeeperState.SyncConnected) {
        connectedSignal.countDown();
    }
}
 

@Override
public void process(WatchedEvent event) { // Watcher interface

    if (event.getState() == KeeperState.SyncConnected) {
        connectedSignal.countDown();
    }
}
 

/**
 * Simulate a zk state change by calling {@link ZkClient#process(WatchedEvent)} directly
 */
public static void simulateZkStateReconnected(RealmAwareZkClient client) {
  ZkClient zkClient = (ZkClient) client;
  WatchedEvent event = new WatchedEvent(EventType.None, KeeperState.Disconnected, null);
  zkClient.process(event);
  event = new WatchedEvent(EventType.None, KeeperState.SyncConnected, null);
  zkClient.process(event);
}
 

/**
 * 当连接成功时调用的
 */
@Override
public void process(WatchedEvent event) {
    if (event.getState() == KeeperState.SyncConnected) {

        LOGGER.info("zk SyncConnected");
        connectedSignal.countDown();

    } else if (event.getState().equals(KeeperState.Disconnected)) {

        // 这时收到断开连接的消息，这里其实无能为力，因为这时已经和ZK断开连接了，只能等ZK再次开启了
        LOGGER.warn("zk Disconnected");

    } else if (event.getState().equals(KeeperState.Expired)) {

        if (!debug) {

            // 这时收到这个信息，表示，ZK已经重新连接上了，但是会话丢失了，这时需要重新建立会话。
            LOGGER.error("zk Expired");

            // just reconnect forever
            reconnect();
        } else {
            LOGGER.info("zk Expired");
        }

    } else if (event.getState().equals(KeeperState.AuthFailed)) {

        LOGGER.error("zk AuthFailed");
    }
}
 

public ZooKeeper connect(String host) throws Exception {
	zk = new ZooKeeper(host, 2101, new Watcher() {
		public void process(WatchedEvent event) {
			if (event.getState() == KeeperState.SyncConnected) {
				connSignal.countDown();
			}
		}
	});
	connSignal.await();
	return zk;
}
 

public ZooKeeper connect(String host) throws IOException, InterruptedException {
    zoo = new ZooKeeper(host, 2000, new Watcher() {
        public void process(WatchedEvent we) {
            if (we.getState() == KeeperState.SyncConnected) {
                connectionLatch.countDown();
            }
        }
    });
    connectionLatch.await();
    return zoo;
}
 

@Override
public void process(WatchedEvent event) {
	if (event.getState() == KeeperState.SyncConnected) {
		conSignal.countDown();
	}
	synchronized (this) {
		if (event.getPath() != null
				&& event.getPath().equals(Constants.zk_start_flag)
				&& event.getType() == Event.EventType.NodeCreated) {
			try {
				if (zk.exists(Constants.zk_znode, false) != null) {
					List<String> list = zk.getChildren(Constants.zk_znode,	true);
					if (list != null && list.size() > 0) {
						for (String str : list) {
							zk.delete(Constants.zk_znode + "/" + str, -1);
						}
					}
					zk.delete(Constants.zk_znode, -1);
					logger.info("delete zookeeper dir successful. It begin to start hadoop task...");
					Recsys.runAllTask();
					
				} 
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}
}
 

public boolean isConnected() {
    return state == KeeperState.SyncConnected;
}
 

public boolean isConnected() {
	return state == KeeperState.SyncConnected;
}
 

@Override
public boolean isConnected() {
    return state == KeeperState.SyncConnected;
}