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.io.network.group.api.driver;
020
021import org.apache.reef.io.network.group.impl.GroupCommunicationMessage;
022
023/**
024 * A node in the Topology representing a Task on the driver.
025 * Impl should maintain state relating to whether task is running/dead and
026 * status of neighboring nodes and send ctrl msgs to the tasks indicating
027 * topology changing events
028 */
029public interface TaskNode {
030
031  String getTaskId();
032
033  int getVersion();
034
035  int getNumberOfChildren();
036
037  TaskNode getParent();
038
039  void setParent(TaskNode parent);
040
041  Iterable<TaskNode> getChildren();
042
043  void addChild(TaskNode child);
044
045  void removeChild(TaskNode taskNode);
046
047  boolean isRunning();
048
049  void onRunningTask();
050
051  void onFailedTask();
052
053  boolean hasChanges();
054
055  boolean isNeighborActive(String neighborId);
056
057  void onReceiptOfAcknowledgement(GroupCommunicationMessage msg);
058
059  void onParentRunning();
060
061  void onParentDead();
062
063  void onChildRunning(String childId);
064
065  void onChildDead(String childId);
066
067  /**
068   * Check if this node is ready for sending.
069   * TopologySetup
070   */
071  void checkAndSendTopologySetupMessage();
072
073  /**
074   * Check if the neighbor node with id source.
075   * is ready for sending TopologySetup
076   * @param source
077   */
078  void checkAndSendTopologySetupMessageFor(String source);
079
080  /**
081   * reset topology setup ensures that update topology is not sent to someone.
082   * who is already updating topology which is usually when they are just
083   * (re)starting
084   *
085   * @return
086   */
087  boolean resetTopologySetupSent();
088
089  void waitForTopologySetupOrFailure();
090
091  void setSibling(TaskNode leaf);
092
093  TaskNode successor();
094
095  void updatingTopology();
096}