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 java.util.concurrent.atomic.AtomicBoolean;
023    
024    /**
025     * Calls {@link System#exit(int)} except from shutdown hooks, to prevent
026     * deadlocks. See http://stackoverflow.com/a/19552359/229031
027     */
028    public class SystemExit {
029    
030      private final AtomicBoolean inShutdownHook = new AtomicBoolean(false);
031    
032      public void exit(int code) {
033        if (!inShutdownHook.get()) {
034          doExit(code);
035        }
036      }
037    
038      public boolean isInShutdownHook() {
039        return inShutdownHook.get();
040      }
041    
042      /**
043       * Declarative approach. I don't know how to get this lifecycle state from Java API.
044       */
045      public void setInShutdownHook() {
046        inShutdownHook.set(true);
047      }
048    
049      void doExit(int code) {
050        System.exit(code);
051      }
052    }