Source code

001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.reef.tests.fail.driver;
020
021import org.apache.reef.tang.annotations.Unit;
022import org.apache.reef.task.Task;
023import org.apache.reef.task.TaskMessage;
024import org.apache.reef.task.TaskMessageSource;
025import org.apache.reef.task.events.CloseEvent;
026import org.apache.reef.task.events.DriverMessage;
027import org.apache.reef.task.events.SuspendEvent;
028import org.apache.reef.task.events.TaskStop;
029import org.apache.reef.util.Optional;
030import org.apache.reef.wake.EventHandler;
031import org.apache.reef.wake.remote.impl.ObjectSerializableCodec;
032
033import javax.inject.Inject;
034import java.util.logging.Level;
035import java.util.logging.Logger;
036
037/**
038 * A basic task that quite successfully does nothing.
039 */
040@Unit
041public final class NoopTask implements Task, TaskMessageSource {
042
043  private static final Logger LOG = Logger.getLogger(NoopTask.class.getName());
044  private static final ObjectSerializableCodec<String> CODEC = new ObjectSerializableCodec<>();
045  private static final TaskMessage INIT_MESSAGE = TaskMessage.from("", CODEC.encode("MESSAGE::INIT"));
046  private transient boolean isRunning = true;
047  private transient Optional<TaskMessage> message = Optional.empty();
048
049  @Inject
050  public NoopTask() {
051    LOG.info("NoopTask created.");
052  }
053
054  @Override
055  public synchronized byte[] call(final byte[] memento) {
056    this.isRunning = true;
057    while (this.isRunning) {
058      try {
059        LOG.info("NoopTask.call(): Waiting for the message.");
060        this.wait();
061      } catch (final InterruptedException ex) {
062        LOG.log(Level.WARNING, "NoopTask.wait() interrupted.", ex);
063      }
064    }
065    LOG.log(Level.INFO, "NoopTask.call(): Exiting with message {0}",
066        CODEC.decode(this.message.orElse(INIT_MESSAGE).get()));
067    return this.message.orElse(INIT_MESSAGE).get();
068  }
069
070  @Override
071  public synchronized Optional<TaskMessage> getMessage() {
072    LOG.log(Level.INFO, "NoopTask.getMessage() invoked: {0}",
073        CODEC.decode(this.message.orElse(INIT_MESSAGE).get()));
074    return this.message;
075  }
076
077  private synchronized void stopTask() {
078    LOG.info("NoopTask.stopTask() invoked.");
079    this.isRunning = false;
080    this.notify();
081  }
082
083  /**
084   * Handler for SuspendEvent.
085   */
086  public class TaskSuspendHandler implements EventHandler<SuspendEvent> {
087    @Override
088    public void onNext(final SuspendEvent suspendEvent) {
089      LOG.info("NoopTask.TaskSuspendHandler.send() invoked.");
090      NoopTask.this.stopTask();
091    }
092  }
093
094  /**
095   * Handler for TaskStop.
096   */
097  public class TaskStopHandler implements EventHandler<TaskStop> {
098    @Override
099    public void onNext(final TaskStop event) {
100      LOG.info("NoopTask.TaskStopHandler.send() invoked.");
101      NoopTask.this.stopTask();
102    }
103  }
104
105  /**
106   * Handler for CloseEvent.
107   */
108  public class TaskCloseHandler implements EventHandler<CloseEvent> {
109    @Override
110    public void onNext(final CloseEvent closeEvent) {
111      LOG.info("NoopTask.TaskCloseHandler.send() invoked.");
112      NoopTask.this.stopTask();
113    }
114  }
115
116  /**
117   * Handler for DriverMessage.
118   */
119  public class DriverMessageHandler implements EventHandler<DriverMessage> {
120    @Override
121    public void onNext(final DriverMessage driverMessage) {
122      final byte[] msg = driverMessage.get().get();
123      LOG.log(Level.INFO, "NoopTask.DriverMessageHandler.send() invoked: {0}", CODEC.decode(msg));
124      synchronized (NoopTask.this) {
125        NoopTask.this.message = Optional.of(TaskMessage.from(NoopTask.this.toString(), msg));
126      }
127    }
128  }
129}