chris@1: /*
chris@1:  *   SONEWS News Server
chris@1:  *   see AUTHORS for the list of contributors
chris@1:  *
chris@1:  *   This program is free software: you can redistribute it and/or modify
chris@1:  *   it under the terms of the GNU General Public License as published by
chris@1:  *   the Free Software Foundation, either version 3 of the License, or
chris@1:  *   (at your option) any later version.
chris@1:  *
chris@1:  *   This program is distributed in the hope that it will be useful,
chris@1:  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
chris@1:  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
chris@1:  *   GNU General Public License for more details.
chris@1:  *
chris@1:  *   You should have received a copy of the GNU General Public License
chris@1:  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
chris@1:  */
chris@1: 
chris@1: package org.sonews.daemon;
chris@1: 
chris@1: import java.sql.SQLException;
chris@1: import java.util.Map;
chris@1: 
chris@1: /**
chris@1:  * Will force all other threads to shutdown cleanly.
chris@1:  * @author Christian Lins
chris@1:  * @since sonews/0.5.0
chris@1:  */
chris@1: class ShutdownHook extends Thread
chris@1: {
chris@1: 
chris@1:   /**
chris@1:    * Called when the JVM exits.
chris@1:    */
chris@1:   @Override
chris@1:   public void run()
chris@1:   {
chris@1:     System.out.println("sonews: Trying to shutdown all threads...");
chris@1: 
chris@1:     Map<Thread, StackTraceElement[]> threadsMap = Thread.getAllStackTraces();
chris@1:     for(Thread thread : threadsMap.keySet())
chris@1:     {
chris@1:       // Interrupt the thread if it's a AbstractDaemon
chris@1:       AbstractDaemon daemon;
chris@1:       if(thread instanceof AbstractDaemon && thread.isAlive())
chris@1:       {
chris@1:         try
chris@1:         {
chris@1:           daemon = (AbstractDaemon)thread;
chris@1:           daemon.shutdownNow();
chris@1:         }
chris@1:         catch(SQLException ex)
chris@1:         {
chris@1:           System.out.println("sonews: " + ex);
chris@1:         }
chris@1:       }
chris@1:     }
chris@1:     
chris@1:     for(Thread thread : threadsMap.keySet())
chris@1:     {
chris@1:       AbstractDaemon daemon;
chris@1:       if(thread instanceof AbstractDaemon && thread.isAlive())
chris@1:       {
chris@1:         daemon = (AbstractDaemon)thread;
chris@1:         System.out.println("sonews: Waiting for " + daemon + " to exit...");
chris@1:         try
chris@1:         {
chris@1:           daemon.join(500);
chris@1:         }
chris@1:         catch(InterruptedException ex)
chris@1:         {
chris@1:           System.out.println(ex.getLocalizedMessage());
chris@1:         }
chris@1:       }
chris@1:     }
chris@1:     
chris@1:     // We have notified all not-sleeping AbstractDaemons of the shutdown;
chris@1:     // all other threads can be simply purged on VM shutdown
chris@1:     
chris@1:     System.out.println("sonews: Clean shutdown.");
chris@1:   }
chris@1:   
chris@1: }