1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 package org.apache.giraph.ooc.command; 20 21 import org.apache.giraph.ooc.OutOfCoreEngine; 22 23 import java.io.IOException; 24 import java.util.concurrent.TimeUnit; 25 26 /** 27 * IOCommand to do nothing regarding moving data to/from disk. 28 */ 29 public class WaitIOCommand extends IOCommand { 30 /** How long should the disk be idle? (in milliseconds) */ 31 private final long waitDuration; 32 33 /** 34 * Constructor 35 * 36 * @param oocEngine out-of-core engine 37 * @param waitDuration duration of wait 38 */ 39 public WaitIOCommand(OutOfCoreEngine oocEngine, long waitDuration) { 40 super(oocEngine, -1); 41 this.waitDuration = waitDuration; 42 } 43 44 @Override 45 public boolean execute() throws IOException { 46 try { 47 TimeUnit.MILLISECONDS.sleep(waitDuration); 48 } catch (InterruptedException e) { 49 throw new IllegalStateException("execute: caught InterruptedException " + 50 "while IO thread is waiting!"); 51 } 52 return true; 53 } 54 55 @Override 56 public IOCommandType getType() { 57 return IOCommandType.WAIT; 58 } 59 60 @Override 61 public String toString() { 62 return "WaitIOCommand: (duration = " + waitDuration + "ms)"; 63 } 64 }