org.apache.curator.framework.recipes.leader.LeaderLatch#addListener

Source File: SimpleLeaderManager.java From mykit-delay with Apache License 2.0

6 votes

public void init() {
    CuratorFrameworkFactory.Builder builder = CuratorFrameworkFactory.builder()
            .connectString(properties.getServerList())
            .retryPolicy(new ExponentialBackoffRetry(properties.getBaseSleepTimeMilliseconds(),
                    properties.getMaxRetries(),
                    properties.getMaxSleepTimeMilliseconds()))
            .namespace(ServerNode.NAMESPACE);
    framework = builder.build();
    framework.start();
    leaderLatch = new LeaderLatch(framework, ServerNode.LEADERLATCH, serverName, LeaderLatch.CloseMode.NOTIFY_LEADER);
    for (LeaderLatchListener listener : listeners) {
        leaderLatch.addListener(listener);
    }
    LOGGER.info("starting Queue Master Slave Model ...");
    start();
}

Source File: StartupRunner.java From liteflow with Apache License 2.0

6 votes

@Override
public void run(String... strings) throws Exception {
    LeaderLatch leaderLatch = new LeaderLatch(client, path);
    leaderLatch.addListener(new LeaderLatchListener() {
        @Override
        public void isLeader() {
            MasterInfo.setIsMaster(true);
            refreshLeaderIp();
            scheduler.start();
        }

        @Override
        public void notLeader() {
            MasterInfo.setIsMaster(false);
            scheduler.stop();
            EventQueue.clear();
        }
    });
    leaderLatch.start();
}

Source File: SimpleLeaderManager.java From sdmq with Apache License 2.0

6 votes

public void init() {
    CuratorFrameworkFactory.Builder builder = CuratorFrameworkFactory.builder()
            .connectString(properties.getServerList())
            .retryPolicy(new ExponentialBackoffRetry(properties.getBaseSleepTimeMilliseconds(),
                    properties.getMaxRetries(),
                    properties.getMaxSleepTimeMilliseconds()))
            .namespace(ServerNode.NAMESPACE);
    framework = builder.build();
    framework.start();
    leaderLatch = new LeaderLatch(framework, ServerNode.LEADERLATCH, serverName, LeaderLatch.CloseMode.NOTIFY_LEADER);
    for (LeaderLatchListener listener : listeners) {
        leaderLatch.addListener(listener);
    }
    LOGGER.info("starting Queue Master Slave Model ...");
    start();
}

Source File: Reaper.java From xian with Apache License 2.0

6 votes

private void addListenerToLeaderLatch(LeaderLatch leaderLatch)
{

    LeaderLatchListener listener = new LeaderLatchListener()
    {
        @Override
        public void isLeader()
        {
            reapingIsActive.set(true);
            for ( PathHolder holder : activePaths.values() )
            {
                schedule(holder, reapingThresholdMs);
            }
        }

        @Override
        public void notLeader()
        {
            reapingIsActive.set(false);
        }
    };
    leaderLatch.addListener(listener);

    reapingIsActive.set(leaderLatch.hasLeadership());
}

Source File: ZookeeperLeaderElector.java From titus-control-plane with Apache License 2.0

6 votes

private LeaderLatch createNewLeaderLatch(String leaderPath) {
    final LeaderLatch newLeaderLatch = new LeaderLatch(curator, leaderPath, "127.0.0.1");

    newLeaderLatch.addListener(
            new LeaderLatchListener() {
                @Override
                public void isLeader() {
                    announceLeader();
                }

                @Override
                public void notLeader() {
                    leaderActivator.stopBeingLeader();
                }
            }, Executors.newSingleThreadExecutor(new DefaultThreadFactory("LeaderLatchListener-%s")));

    return newLeaderLatch;
}

Source File: DefaultLeaderElector.java From x-pipe with Apache License 2.0

6 votes

@Override
public void elect() throws Exception {
	
	zkClient.createContainers(ctx.getLeaderElectionZKPath());
	
	latch = new LeaderLatch(zkClient, ctx.getLeaderElectionZKPath(), ctx.getLeaderElectionID());
	latch.addListener(new LeaderLatchListener() {

		@Override
		public void notLeader() {
		}

		@Override
		public void isLeader() {
		}
	});

	latch.start();
	logger.info("[elect]{}", ctx);
}

Source File: LeaderElectHandler.java From DBus with Apache License 2.0

5 votes

@SuppressWarnings("resource")
@Override
public void process() {
    try {
        CuratorFramework _curator = CuratorContainer.getInstance().getCurator();
        ZkVo conf = HeartBeatConfigContainer.getInstance().getZkConf();
        CuratorContainer.getInstance().createZkNode(conf.getLeaderPath());

        // 获取进程ID和服务器hostName
        final BrokerInfoVo brokerInfo = new BrokerInfoVo();
        String name = ManagementFactory.getRuntimeMXBean().getName();
        String[] pidAndHostName = StringUtils.split(name, "@");
        brokerInfo.setPid(pidAndHostName[0]);
        brokerInfo.setHostName(pidAndHostName[1]);
        brokerInfo.setIp(InetAddress.getLocalHost().getHostAddress());
        LeaderLatch ll = new LeaderLatch(_curator, conf.getLeaderPath(), JsonUtil.toJson(brokerInfo));

        ll.addListener(new LeaderLatchListener() {
            @Override
            public void notLeader() {
                LoggerFactory.getLogger().error("本机现在切换到非leader状态,准备终止当前进程PID:{}", brokerInfo.getPid());
                System.exit(-1);
            }

            @Override
            public void isLeader() {
                LoggerFactory.getLogger().info("本机现在切换到leader状态.");
            }
        });

        ll.start();
        ll.await();
    } catch (Exception e) {
        throw new RuntimeException("选举leader时发生错误!", e);
    }
}

Source File: ZkHaGuard.java From fountain with Apache License 2.0

5 votes

/**
 * 阻塞式的初始化和Zookeeper的连接，这个方法在一个容器生命周期中只允许允许一次。
 * <p/>
 * 和zookeeper之间的连接遵循每实例一个ZkClientProvider的方式，这样当实例内部有多个同步线程的时候，
 * 可以共享一个ZkClientProvider，状态都是一致的，避免有些线程是leader，有些是standby的情况。
 * <p/>
 * 改方法是全异步的，如果zookeeper连接不上，也会返回。但是一般上层应用拿不到leader latch，不会成为leader。
 * 而且<code>apache.zookeeper.ClientCnxn</code>包的日志会打印如下：
 * <pre>
 *     Unable to read additional data from server sessionid 0x0, likely server has closed socket, closing socket
 *     connection and attempting reconnect
 * </pre>
 * 参数<code>name</code>标示同步线程的名称，默认的话只有一个可以初始化好和zk的连接，其他的都不再重复初始化了。
 */
@Override
public void init(String name) {
    if (!state.compareAndSet(State.LATENT, State.STARTED)) {
        logger.debug("ZkHaGuard can only be initialized once because LeaderLatch should be singleton");
        return;
    }

    if (zkClientProvider == null) {
        throw new IllegalStateException("ZkClientProvider should not be null");
    }
    logger.info("LeaderLatch will start soon by " + name);
    zkClientProvider.init();
    leaderLatch = new LeaderLatch(zkClientProvider.provideClient(), latchPath, NetUtils.getLocalHostIP());
    leaderLatch.addListener(new LeaderLatchListener() {
        @Override
        public void isLeader() {
            logger.info("This instance is leader");
        }

        @Override
        public void notLeader() {
            logger.warn("This instance is NOT leader");
        }
    });
    try {
        leaderLatch.start();
    } catch (Exception e) {
        throw new RuntimeException("Leader latch init failed", e);
    }
    logger.info("LeaderLatch starts by " + name + " asynchronously");
}

Source File: ClusterSyncManager.java From Decision with Apache License 2.0

5 votes

public void start() throws Exception {
    client.start();
    client.getZookeeperClient().blockUntilConnectedOrTimedOut();
    leaderLatch = new LeaderLatch(client, latchpath, id);

    ClusterSyncManagerLeaderListener listener = new ClusterSyncManagerLeaderListener(failOverTask, getNode());
    leaderLatch.addListener(listener);

    leaderLatch.start();
}

Source File: OracleServer.java From fluo with Apache License 2.0

4 votes

public synchronized void start() throws Exception {
  if (started) {
    throw new IllegalStateException();
  }

  curatorFramework = CuratorUtil.newAppCurator(env.getConfiguration());
  curatorFramework.getConnectionStateListenable().addListener(cnxnListener);
  curatorFramework.start();

  while (!cnxnListener.isConnected()) {
    UtilWaitThread.sleep(200);
  }

  final InetSocketAddress addr = startServer();

  String leaderId = HostUtil.getHostName() + ":" + addr.getPort();
  leaderLatch = new LeaderLatch(curatorFramework, ZookeeperPath.ORACLE_SERVER, leaderId);
  log.info("Leader ID = " + leaderId);
  execService = Executors.newSingleThreadExecutor(new FluoThreadFactory("Oracle Server Worker"));
  leaderLatch.addListener(new LeaderLatchListener() {
    @Override
    public void notLeader() {
      isLeader = false;

      if (started) {
        // if we stopped the server manually, we shouldn't halt
        Halt.halt("Oracle has lost leadership unexpectedly and is now halting.");
      }
    }

    @Override
    public void isLeader() {
      assumeLeadership();
    }
  }, execService);
  leaderLatch.start();

  pathChildrenCache = new PathChildrenCache(curatorFramework, oraclePath, true);
  pathChildrenCache.getListenable().addListener(this);
  pathChildrenCache.start();

  while (!cnxnListener.isConnected()) {
    UtilWaitThread.sleep(200);
  }

  log.info("Listening " + addr);

  started = true;
}

Java Code Examples for org.apache.curator.framework.recipes.leader.LeaderLatch#addListener()