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     */
020    package org.sonar.process;
021    
022    import org.apache.commons.io.IOUtils;
023    import org.slf4j.LoggerFactory;
024    
025    import javax.annotation.Nullable;
026    
027    public class ProcessUtils {
028    
029      private ProcessUtils() {
030        // only static stuff
031      }
032    
033      /**
034       * Do not abuse to this method. It uses exceptions to get status.
035       * @return false if process is null or terminated, else true.
036       */
037      public static boolean isAlive(@Nullable Process process) {
038        boolean alive = false;
039        if (process != null) {
040          try {
041            process.exitValue();
042          } catch (IllegalThreadStateException ignored) {
043            alive = true;
044          }
045        }
046        return alive;
047      }
048    
049      /**
050       * Send kill signal to stop process. Shutdown hooks are executed. It's the equivalent of SIGTERM on Linux.
051       * Correctly tested on Java 6 and 7 on both Mac/MSWindows
052       * @return true if the signal is sent, false if process is already down
053       */
054      public static boolean sendKillSignal(@Nullable Process process) {
055        boolean sentSignal = false;
056        if (isAlive(process)) {
057          try {
058            process.destroy();
059            sentSignal = true;
060          } catch (Exception e) {
061            LoggerFactory.getLogger(ProcessUtils.class).error("Fail to kill " + process);
062          }
063        }
064        return sentSignal;
065      }
066    
067      public static void closeStreams(@Nullable Process process) {
068        if (process!=null) {
069          IOUtils.closeQuietly(process.getInputStream());
070          IOUtils.closeQuietly(process.getOutputStream());
071          IOUtils.closeQuietly(process.getErrorStream());
072        }
073      }
074    }