+++ /dev/null
-/* java.lang.InheritableThreadLocal
- Copyright (C) 2000, 2001 Free Software Foundation, Inc.
-
-This file is part of GNU Classpath.
-
-GNU Classpath is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
-any later version.
-
-GNU Classpath is distributed in the hope that it will be useful, but
-WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with GNU Classpath; see the file COPYING. If not, write to the
-Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
-02111-1307 USA.
-
-Linking this library statically or dynamically with other modules is
-making a combined work based on this library. Thus, the terms and
-conditions of the GNU General Public License cover the whole
-combination.
-
-As a special exception, the copyright holders of this library give you
-permission to link this library with independent modules to produce an
-executable, regardless of the license terms of these independent
-modules, and to copy and distribute the resulting executable under
-terms of your choice, provided that you also meet, for each linked
-independent module, the terms and conditions of the license of that
-module. An independent module is a module which is not derived from
-or based on this library. If you modify this library, you may extend
-this exception to your version of the library, but you are not
-obligated to do so. If you do not wish to do so, delete this
-exception statement from your version. */
-
-package java.lang;
-
-import java.util.Iterator;
-import java.util.HashSet;
-import java.util.Map;
-import java.util.Set;
-import java.util.WeakHashMap;
-
-/**
- * ThreadLocal whose value is inherited by child Threads.
- * The value of the InheritableThreadLocal associated with the (parent) Thread
- * on the moment that it creates a new (child) Thread is set as the value that
- * is associated with the new (child) Thread.
- * <p>
- * It is possible to make the value associated with the child Thread a function
- * of the value that is associated with the parent Thread by overriding the
- * <code>childValue()</code> method.
- *
- * @since 1.2
- * @author Mark Wielaard (mark@klomp.org)
- */
-public class InheritableThreadLocal extends ThreadLocal {
-
- /**
- * Maps Threads to a Set of InheritableThreadLocals
- * (the heritage of that Thread).
- * Uses a WeakHashMap so if the Thread is garbage collected the reference
- * to that Set disappears.
- * Both <code>AddToHeritage</code> access and modify it so they have to
- * synchronize on the threadMap when they do.
- */
- private static Map threadMap = new WeakHashMap();
-
- /**
- * Creates a new InheritableThreadLocal that has no values associated
- * with it yet.
- */
- public InheritableThreadLocal() {
- super();
- }
-
- /**
- * Determines the value associated with a newly created child Thread
- * as a function of the value associated with the currently executing
- * (parent) Thread.
- * <p>
- * The default implementation just returns the parentValue.
- */
- protected Object childValue(Object parentValue) {
- return parentValue;
- }
-
- /**
- * Adds this <code>InheritableThreadLocal</code> to the heritage of the
- * current Thread and returns the value of the <code>ThreadLocal</code>
- * for the Thread. The value will be either the last value that the
- * current Thread has set, or the childValue of the last value that the
- * parent Thread set before the current Thread was created, or the
- * initialValue of the <code>ThreadLocal</code>.
- *
- * @see ThreadLocal#get()
- */
- public Object get() {
- addToHeritage();
- return super.get();
- }
-
- /**
- * Adds this <code>InheritableThreadLocal</code> to the heritage of the
- * current Thread and sets the value of the <code>ThreadLocal</code>
- * for the Thread.
- *
- * @see ThreadLocal#set(Object)
- */
- public void set(Object value) {
- addToHeritage();
- super.set(value);
- }
-
- /**
- * Adds this <code>InheritableThreadLocal</code> to the heritage
- * of the current Thread.
- */
- private void addToHeritage() {
- Thread currentThread = Thread.currentThread();
- Set heritage;
- synchronized(threadMap) {
- heritage = (Set)threadMap.get(currentThread);
- }
- // Note that we don't have to synchronize on the heritage Set
- // since only this Thread (or the parent Thread when creating
- // the heritage) ever modifies it.
- if (heritage == null) {
- heritage = new HashSet();
- synchronized(threadMap) {
- threadMap.put(currentThread, heritage);
- }
- }
- if (!heritage.contains(this)) {
- heritage.add(this);
- }
- }
-
- /**
- * Generates the childValues of all <code>InheritableThreadLocal</code>s
- * that are in the heritage of the current Thread for the newly created
- * childThread.
- * Should be called from the contructor of java.lang.Thread.
- */
- static void newChildThread(Thread childThread) {
- // The currentThread is the parent of the new thread
- Thread parentThread = Thread.currentThread();
-
- // Inherit all the InheritableThreadLocals of the parent thread
- Set heritage;
- synchronized(threadMap) {
- heritage = (Set)threadMap.get(parentThread);
- }
- // Note that we don't have to synchronize on the heritage Set
- // since only this Thread (or the parent Thread when creating
- // the heritage) ever modifies it.
- if (heritage != null) {
- synchronized(threadMap) {
- threadMap.put(childThread, new HashSet(heritage));
- }
- // And constructs all the new child values
- // (has to be done now that we are executing in the parentThread)
- Iterator it = heritage.iterator();
- while (it.hasNext()) {
- InheritableThreadLocal local =
- (InheritableThreadLocal) it.next();
- // Note that the parentValue cannot be null
- // If it was it would not be in the heritage
- Object parentValue = local.get(parentThread).getValue();
- Object childValue = local.childValue(parentValue);
- ThreadLocal.Value v = new ThreadLocal.Value(childValue);
- local.set(childThread, v);
- }
- }
- }
-}
projects / msp430-gcc.git / blobdiff