/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package org.apache.giraph.ooc.command;
  
  import org.apache.giraph.ooc.OutOfCoreEngine;
  
  import java.io.IOException;
  import java.util.concurrent.TimeUnit;
  
  /**
   * IOCommand to do nothing regarding moving data to/from disk.
   */
  public class WaitIOCommand extends IOCommand {
    /** How long should the disk be idle? (in milliseconds) */
    private final long waitDuration;
  
    /**
     * Constructor
     *
     * @param oocEngine out-of-core engine
     * @param waitDuration duration of wait
     */
    public WaitIOCommand(OutOfCoreEngine oocEngine, long waitDuration) {
      super(oocEngine, -1);
      this.waitDuration = waitDuration;
    }
  
    @Override
    public boolean execute() throws IOException {
      try {
        TimeUnit.MILLISECONDS.sleep(waitDuration);
      } catch (InterruptedException e) {
        throw new IllegalStateException("execute: caught InterruptedException " +
            "while IO thread is waiting!");
      }
      return true;
    }
  
    @Override
    public IOCommandType getType() {
      return IOCommandType.WAIT;
    }
  
    @Override
    public String toString() {
      return "WaitIOCommand: (duration = " + waitDuration + "ms)";
    }
  }