001/*
002 * SonarQube, open source software quality management tool.
003 * Copyright (C) 2008-2014 SonarSource
004 * mailto:contact AT sonarsource DOT com
005 *
006 * SonarQube is free software; you can redistribute it and/or
007 * modify it under the terms of the GNU Lesser General Public
008 * License as published by the Free Software Foundation; either
009 * version 3 of the License, or (at your option) any later version.
010 *
011 * SonarQube is distributed in the hope that it will be useful,
012 * but WITHOUT ANY WARRANTY; without even the implied warranty of
013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014 * Lesser General Public License for more details.
015 *
016 * You should have received a copy of the GNU Lesser General Public License
017 * along with this program; if not, write to the Free Software Foundation,
018 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
019 */
020package org.sonar.process;
021
022import org.slf4j.LoggerFactory;
023
024/**
025 * This watchdog asks for graceful termination of process when the file
026 * <process_key>.stop is created in temp directory.
027 */
028public class StopWatcher extends Thread {
029
030  private final Stoppable stoppable;
031  private final ProcessCommands commands;
032  private boolean watching = true;
033  private final long delayMs;
034
035  public StopWatcher(ProcessCommands commands, Stoppable stoppable) {
036    this(commands, stoppable, 500L);
037  }
038
039  StopWatcher(ProcessCommands commands, Stoppable stoppable, long delayMs) {
040    super("Stop Watcher");
041    this.commands = commands;
042    this.stoppable = stoppable;
043    this.delayMs = delayMs;
044  }
045
046  @Override
047  public void run() {
048    try {
049      while (watching) {
050        if (commands.askedForStop()) {
051          LoggerFactory.getLogger(getClass()).info("Stopping process");
052          stoppable.stopAsync();
053          watching = false;
054        } else {
055          try {
056            Thread.sleep(delayMs);
057          } catch (InterruptedException ignored) {
058            watching = false;
059          }
060        }
061      }
062    } finally {
063      commands.endWatch();
064    }
065  }
066
067  public void stopWatching() {
068    watching = false;
069  }
070}