1 /*
   2  * Copyright (c) 2001, 2003, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.corba.se.impl.activation;
  27 
  28 import java.util.*;
  29 import com.sun.corba.se.impl.orbutil.ORBConstants;
  30 
  31 /** ProcessMonitorThread is started when ServerManager is instantiated. The
  32   * thread wakes up every minute (This can be changed by setting sleepTime) and
  33   * makes sure that all the processes (Servers) registered with the ServerTool
  34   * are healthy. If not the state in ServerTableEntry will be changed to
  35   * De-Activated.
  36   * Note: This thread can be killed from the main thread by calling
  37   *       interrupThread()
  38   */
  39 public class ProcessMonitorThread extends java.lang.Thread {
  40     private HashMap serverTable;
  41     private int sleepTime;
  42     private static ProcessMonitorThread instance = null;
  43 
  44     private ProcessMonitorThread( HashMap ServerTable, int SleepTime ) {
  45         serverTable = ServerTable;
  46         sleepTime = SleepTime;
  47     }
  48 
  49     public void run( ) {
  50         while( true ) {
  51             try {
  52                 // Sleep's for a specified time, before checking
  53                 // the Servers health. This will repeat as long as
  54                 // the ServerManager (ORBD) is up and running.
  55                 Thread.sleep( sleepTime );
  56             } catch( java.lang.InterruptedException e ) {
  57                 break;
  58             }
  59             Iterator serverList;
  60             synchronized ( serverTable ) {
  61                 // Check each ServerTableEntry to make sure that they
  62                 // are in the right state.
  63                 serverList = serverTable.values().iterator();
  64             }
  65             try {
  66                 checkServerHealth( serverList );
  67             } catch( ConcurrentModificationException e ) {
  68                 break;
  69             }
  70         }
  71     }
  72 
  73     private void checkServerHealth( Iterator serverList ) {
  74         if( serverList == null ) return;
  75         while (serverList.hasNext( ) ) {
  76             ServerTableEntry entry = (ServerTableEntry) serverList.next();
  77             entry.checkProcessHealth( );
  78         }
  79     }
  80 
  81     static void start( HashMap serverTable ) {
  82         int sleepTime = ORBConstants.DEFAULT_SERVER_POLLING_TIME;
  83 
  84         String pollingTime = System.getProperties().getProperty(
  85             ORBConstants.SERVER_POLLING_TIME );
  86 
  87         if ( pollingTime != null ) {
  88             try {
  89                 sleepTime = Integer.parseInt( pollingTime );
  90             } catch (Exception e ) {
  91                 // Too late to complain, Just use the default
  92                 // sleepTime
  93             }
  94         }
  95 
  96         instance = new ProcessMonitorThread( serverTable,
  97             sleepTime );
  98         instance.setDaemon( true );
  99         instance.start();
 100     }
 101 
 102     static void interruptThread( ) {
 103         instance.interrupt();
 104     }
 105 }