jurt/com/sun/star/lib/uno/environments/remote/ThreadPoolManager.java

   1 /*
   2  * This file is part of the LibreOffice project.
   3  *
   4  * This Source Code Form is subject to the terms of the Mozilla Public
   5  * License, v. 2.0. If a copy of the MPL was not distributed with this
   6  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   7  *
   8  * This file incorporates work covered by the following license notice:
   9  *
  10  *   Licensed to the Apache Software Foundation (ASF) under one or more
  11  *   contributor license agreements. See the NOTICE file distributed
  12  *   with this work for additional information regarding copyright
  13  *   ownership. The ASF licenses this file to you under the Apache
  14  *   License, Version 2.0 (the "License"); you may not use this file
  15  *   except in compliance with the License. You may obtain a copy of
  16  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  17  */
  18
  19 package com.sun.star.lib.uno.environments.remote;
  20
  21 /**
  22  * Manages the UNO thread pool factory.
  23  *
  24  * <P>The thread pool factory is a process-wide resource.  It is important that
  25  * all UNO environments within a process share the same thread pool mechanisms:
  26  * if a synchronous UNO call is bridged out from one local UNO environment over
  27  * one remote bridge, and recursively calls back into another local UNO
  28  * environment over another remote bridge, the code in the second environment
  29  * should be executed in the thread that did the original call from the first
  30  * environment.</P>
  31  *
  32  * <P>There are both a Java and a native thread pool factory.  A pure Java
  33  * process will always use the Java thread pool factory.  A mixed process uses
  34  * the system property <CODE>org.openoffice.native</CODE> (to be set by the
  35  * native code that starts the JVM) to determine which implementation
  36  * to use.</P>
  37  */
  38 public final class ThreadPoolManager {
  39     /**
  40      * Creates a thread pool instance.
  41      *
  42      * @return a new thread pool instance; will never be <CODE>null</CODE>.
  43      */
  44     public static synchronized IThreadPool create() {
  45         if (useNative) {
  46             return new NativeThreadPool();
  47         } else {
  48             if (javaFactory == null) {
  49                 javaFactory = new JavaThreadPoolFactory();
  50             }
  51             return javaFactory.createThreadPool();
  52         }
  53     }
  54
  55     /**
  56      * Leads to using the native thread pool factory, unless a Java thread pool
  57      * has already been created.
  58      *
  59      * @return <CODE>false</CODE> if a Java thread pool has already been created.
  60      */
  61     public static synchronized boolean useNative() {
  62         useNative = javaFactory == null;
  63         return useNative;
  64     }
  65
  66     private static boolean useNative
  67     = System.getProperty("org.openoffice.native") != null;
  68     private static JavaThreadPoolFactory javaFactory = null;
  69
  70     private ThreadPoolManager() {} // do not instantiate
  71 }