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.task; 020 021import org.apache.reef.annotations.Unstable; 022import org.apache.reef.annotations.audience.Public; 023import org.apache.reef.annotations.audience.TaskSide; 024import org.apache.reef.runtime.common.evaluator.HeartBeatManager; 025 026import javax.inject.Inject; 027 028/** 029 * Helper class for immediately sending heartbeat messages. 030 * This can be used together with TaskMessageSource to push urgent messages to the Driver. 031 * <p> 032 * CAUTION: Do not overuse as the Driver can be saturated with heartbeats. 033 * 034 * @see <a href="https://issues.apache.org/jira/browse/REEF-33">REEF-33</a> for the ongoing discussion of 035 * alternatives to this design. 036 */ 037@TaskSide 038@Public 039@Unstable 040public class HeartBeatTriggerManager { 041 private final HeartBeatManager heartBeatManager; 042 043 @Inject 044 HeartBeatTriggerManager(final HeartBeatManager heartBeatManager) { 045 this.heartBeatManager = heartBeatManager; 046 } 047 048 /** 049 * Immediately send a heartbeat message to the Driver. 050 */ 051 public void triggerHeartBeat() { 052 this.heartBeatManager.sendHeartbeat(); 053 } 054}