Examples with WatchedEvent org.apache.zookeeper.WatchedEvent used on opensource projects

Example 31 with WatchedEvent

use of org.apache.zookeeper.WatchedEvent in project curator by Netflix.

the class CuratorZKClientBridge method connect.

@Override
public void connect(final Watcher watcher) {
    if (watcher != null) {
        CuratorListener localListener = new CuratorListener() {

            @Override
            public void eventReceived(CuratorFramework client, CuratorEvent event) throws Exception {
                if (event.getWatchedEvent() != null) {
                    watcher.process(event.getWatchedEvent());
                }
            }
        };
        curator.getCuratorListenable().addListener(localListener);
        listener.set(localListener);
        try {
            BackgroundCallback callback = new BackgroundCallback() {

                @Override
                public void processResult(CuratorFramework client, CuratorEvent event) throws Exception {
                    WatchedEvent fakeEvent = new WatchedEvent(Watcher.Event.EventType.None, curator.getZookeeperClient().isConnected() ? Watcher.Event.KeeperState.SyncConnected : Watcher.Event.KeeperState.Disconnected, null);
                    watcher.process(fakeEvent);
                }
            };
            curator.checkExists().inBackground(callback).forPath("/foo");
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}

Example 32 with WatchedEvent

use of org.apache.zookeeper.WatchedEvent in project pinpoint by naver.

the class ZookeeperClusterService method setUp.

@PostConstruct
@Override
public void setUp() throws KeeperException, IOException, InterruptedException {
    if (!config.isClusterEnable()) {
        logger.info("pinpoint-collector cluster disable.");
        return;
    }
    switch(this.serviceState.getCurrentState()) {
        case NEW:
            if (this.serviceState.changeStateInitializing()) {
                logger.info("{} initialization started.", this.getClass().getSimpleName());
                ClusterManagerWatcher watcher = new ClusterManagerWatcher();
                this.client = new DefaultZookeeperClient(config.getClusterAddress(), config.getClusterSessionTimeout(), watcher);
                this.client.connect();
                this.profilerClusterManager = new ZookeeperProfilerClusterManager(client, serverIdentifier, clusterPointRouter.getTargetClusterPointRepository());
                this.profilerClusterManager.start();
                this.webClusterManager = new ZookeeperWebClusterManager(client, PINPOINT_WEB_CLUSTER_PATH, serverIdentifier, clusterConnectionManager);
                this.webClusterManager.start();
                this.serviceState.changeStateStarted();
                logger.info("{} initialization completed.", this.getClass().getSimpleName());
                if (client.isConnected()) {
                    WatcherEvent watcherEvent = new WatcherEvent(EventType.None.getIntValue(), KeeperState.SyncConnected.getIntValue(), "");
                    WatchedEvent event = new WatchedEvent(watcherEvent);
                    watcher.process(event);
                }
            }
            break;
        case INITIALIZING:
            logger.info("{} already initializing.", this.getClass().getSimpleName());
            break;
        case STARTED:
            logger.info("{} already started.", this.getClass().getSimpleName());
            break;
        case DESTROYING:
            throw new IllegalStateException("Already destroying.");
        case STOPPED:
            throw new IllegalStateException("Already stopped.");
        case ILLEGAL_STATE:
            throw new IllegalStateException("Invalid State.");
    }
}

Example 33 with WatchedEvent

use of org.apache.zookeeper.WatchedEvent in project druid by druid-io.

the class LoadQueuePeon method processSegmentChangeRequest.

private void processSegmentChangeRequest() {
    if (currentlyProcessing == null) {
        if (!segmentsToDrop.isEmpty()) {
            currentlyProcessing = segmentsToDrop.firstEntry().getValue();
            log.info("Server[%s] dropping [%s]", basePath, currentlyProcessing.getSegmentIdentifier());
        } else if (!segmentsToLoad.isEmpty()) {
            currentlyProcessing = segmentsToLoad.firstEntry().getValue();
            log.info("Server[%s] loading [%s]", basePath, currentlyProcessing.getSegmentIdentifier());
        } else {
            return;
        }
        try {
            if (currentlyProcessing == null) {
                if (!stopped) {
                    log.makeAlert("Crazy race condition! server[%s]", basePath).emit();
                }
                actionCompleted();
                return;
            }
            log.info("Server[%s] processing segment[%s]", basePath, currentlyProcessing.getSegmentIdentifier());
            final String path = ZKPaths.makePath(basePath, currentlyProcessing.getSegmentIdentifier());
            final byte[] payload = jsonMapper.writeValueAsBytes(currentlyProcessing.getChangeRequest());
            curator.create().withMode(CreateMode.EPHEMERAL).forPath(path, payload);
            processingExecutor.schedule(new Runnable() {

                @Override
                public void run() {
                    try {
                        if (curator.checkExists().forPath(path) != null) {
                            failAssign(new ISE("%s was never removed! Failing this operation!", path));
                        }
                    } catch (Exception e) {
                        failAssign(e);
                    }
                }
            }, config.getLoadTimeoutDelay().getMillis(), TimeUnit.MILLISECONDS);
            final Stat stat = curator.checkExists().usingWatcher(new CuratorWatcher() {

                @Override
                public void process(WatchedEvent watchedEvent) throws Exception {
                    switch(watchedEvent.getType()) {
                        case NodeDeleted:
                            entryRemoved(watchedEvent.getPath());
                    }
                }
            }).forPath(path);
            if (stat == null) {
                final byte[] noopPayload = jsonMapper.writeValueAsBytes(new SegmentChangeRequestNoop());
                // Create a node and then delete it to remove the registered watcher.  This is a work-around for
                // a zookeeper race condition.  Specifically, when you set a watcher, it fires on the next event
                // that happens for that node.  If no events happen, the watcher stays registered foreverz.
                // Couple that with the fact that you cannot set a watcher when you create a node, but what we
                // want is to create a node and then watch for it to get deleted.  The solution is that you *can*
                // set a watcher when you check to see if it exists so, we first create the node and then set a
                // watcher on its existence.  However, if already does not exist by the time the existence check
                // returns, then the watcher that was set will never fire (nobody will ever create the node
                // again) and thus lead to a slow, but real, memory leak.  So, we create another node to cause
                // that watcher to fire and delete it right away.
                //
                // We do not create the existence watcher first, because then it will fire when we create the
                // node and we'll have the same race when trying to refresh that watcher.
                curator.create().withMode(CreateMode.EPHEMERAL).forPath(path, noopPayload);
                entryRemoved(path);
            }
        } catch (Exception e) {
            failAssign(e);
        }
    } else {
        log.info("Server[%s] skipping doNext() because something is currently loading[%s].", basePath, currentlyProcessing.getSegmentIdentifier());
    }
}

Example 34 with WatchedEvent

use of org.apache.zookeeper.WatchedEvent in project weave by continuuity.

the class AbstractZKServiceController method actOnExists.

private void actOnExists(final String path, final Runnable action) {
    // Watch for node existence.
    final AtomicBoolean nodeExists = new AtomicBoolean(false);
    Futures.addCallback(zkClient.exists(path, new Watcher() {

        @Override
        public void process(WatchedEvent event) {
            // Other event type would be handled by the action.
            if (event.getType() == Event.EventType.NodeCreated && nodeExists.compareAndSet(false, true)) {
                action.run();
            }
        }
    }), new FutureCallback<Stat>() {

        @Override
        public void onSuccess(Stat result) {
            if (result != null && nodeExists.compareAndSet(false, true)) {
                action.run();
            }
        }

        @Override
        public void onFailure(Throwable t) {
            LOG.error("Failed in exists call to {}. Shutting down service.", path, t);
            forceShutDown();
        }
    }, Threads.SAME_THREAD_EXECUTOR);
}

Example 35 with WatchedEvent

use of org.apache.zookeeper.WatchedEvent in project yyl_example by Relucent.

the class Test1 method main.

public static void main(String[] args) throws Exception {
    ZooKeeper zk = new ZooKeeper("localhost:2181", 1000, new Watcher() {

        // 监控所有被触发的事件
        public void process(WatchedEvent event) {
            System.out.println("已经触发了" + event.getType() + "事件！");
        }
    });
    // 创建一个目录节点
    zk.create("/testRootPath", "testRootData".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
    // 创建一个子目录节点
    zk.create("/testRootPath/testChildPathOne", "testChildDataOne".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
    System.out.println(new String(zk.getData("/testRootPath", false, null)));
    // 取出子目录节点列表
    System.out.println(zk.getChildren("/testRootPath", true));
    // 修改子目录节点数据
    zk.setData("/testRootPath/testChildPathOne", "modifyChildDataOne".getBytes(), -1);
    System.out.println("目录节点状态：[" + zk.exists("/testRootPath", true) + "]");
    // 创建另外一个子目录节点
    zk.create("/testRootPath/testChildPathTwo", "testChildDataTwo".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
    System.out.println(new String(zk.getData("/testRootPath/testChildPathTwo", true, null)));
    // 删除子目录节点
    zk.delete("/testRootPath/testChildPathTwo", -1);
    zk.delete("/testRootPath/testChildPathOne", -1);
    // 删除父目录节点
    zk.delete("/testRootPath", -1);
    // 关闭连接
    zk.close();
}