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.runtime.common.driver.idle; 020 021import org.apache.reef.tang.InjectionFuture; 022import org.apache.reef.wake.EventHandler; 023import org.apache.reef.wake.time.Clock; 024import org.apache.reef.wake.time.runtime.event.IdleClock; 025 026import javax.inject.Inject; 027 028/** 029 * Informs the DriverIdleManager of clock idleness. 030 */ 031public final class ClockIdlenessSource implements DriverIdlenessSource, EventHandler<IdleClock> { 032 private static final String COMPONENT_NAME = "Clock"; 033 private static final String IDLE_REASON = "The clock reported idle."; 034 private static final IdleMessage IDLE_MESSAGE = new IdleMessage(COMPONENT_NAME, IDLE_REASON, true); 035 private static final String NOT_IDLE_REASON = "The clock reported not idle."; 036 private static final IdleMessage NOT_IDLE_MESSAGE = new IdleMessage(COMPONENT_NAME, NOT_IDLE_REASON, false); 037 038 private final InjectionFuture<DriverIdleManager> driverIdleManager; 039 private final Clock clock; 040 041 @Inject 042 ClockIdlenessSource(final InjectionFuture<DriverIdleManager> driverIdleManager, final Clock clock) { 043 this.driverIdleManager = driverIdleManager; 044 this.clock = clock; 045 } 046 047 @Override 048 public synchronized IdleMessage getIdleStatus() { 049 if (this.clock.isIdle()) { 050 return IDLE_MESSAGE; 051 } else { 052 return NOT_IDLE_MESSAGE; 053 } 054 } 055 056 @Override 057 public synchronized void onNext(final IdleClock idleClock) { 058 this.driverIdleManager.get().onPotentiallyIdle(IDLE_MESSAGE); 059 } 060}