content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.distributedlog.zk;
  
  import static org.junit.Assert.assertEquals;
  
  import java.util.LinkedList;
  import java.util.List;
  import java.util.concurrent.CountDownLatch;
  import org.apache.bookkeeper.stats.NullStatsLogger;
  import org.apache.zookeeper.WatchedEvent;
  import org.apache.zookeeper.Watcher;
  import org.junit.Test;
  
  
  
  
  /**
   * Test Case for {@link ZKWatcherManager}.
   */
  public class TestZKWatcherManager {
  
      @Test(timeout = 60000)
      public void testRegisterUnregisterWatcher() throws Exception {
          ZKWatcherManager watcherManager = ZKWatcherManager.newBuilder()
                  .name("test-register-unregister-watcher")
                  .zkc(null)
                  .statsLogger(NullStatsLogger.INSTANCE)
                  .build();
          String path = "/test-register-unregister-watcher";
          final List<WatchedEvent> events = new LinkedList<WatchedEvent>();
          final CountDownLatch latch = new CountDownLatch(2);
          Watcher watcher = new Watcher() {
              @Override
              public void process(WatchedEvent event) {
                  events.add(event);
                  latch.countDown();
              }
          };
          watcherManager.registerChildWatcher(path, watcher);
  
          // fire the event
          WatchedEvent event0 = new WatchedEvent(
                  Watcher.Event.EventType.NodeCreated,
                  Watcher.Event.KeeperState.SyncConnected,
                  path);
          WatchedEvent event1 = new WatchedEvent(
                  Watcher.Event.EventType.None,
                  Watcher.Event.KeeperState.SyncConnected,
                  path);
          WatchedEvent event2 = new WatchedEvent(
                  Watcher.Event.EventType.NodeChildrenChanged,
                  Watcher.Event.KeeperState.SyncConnected,
                  path);
          watcher.process(event1);
          watcher.process(event2);
  
          latch.await();
  
          assertEquals(2, events.size());
          assertEquals(event1, events.get(0));
          assertEquals(event2, events.get(1));
  
          // unregister watcher
          watcherManager.unregisterChildWatcher(path, watcher, true);
          // unregister gauges
          watcherManager.unregisterGauges();
          assertEquals(0, watcherManager.childWatches.size());
      }
  }
  