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Diffstat (limited to 'libjava/javax/swing/undo/UndoableEditSupport.java')
| -rw-r--r-- | libjava/javax/swing/undo/UndoableEditSupport.java | 271 |
1 files changed, 0 insertions, 271 deletions
diff --git a/libjava/javax/swing/undo/UndoableEditSupport.java b/libjava/javax/swing/undo/UndoableEditSupport.java deleted file mode 100644 index 227d2824779..00000000000 --- a/libjava/javax/swing/undo/UndoableEditSupport.java +++ /dev/null @@ -1,271 +0,0 @@ -/* UndoableEditSupport.java -- - Copyright (C) 2002, 2003, 2004, 2005 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., 51 Franklin Street, Fifth Floor, Boston, MA -02110-1301 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 javax.swing.undo; - -import java.util.Iterator; -import java.util.Vector; - -import javax.swing.event.UndoableEditEvent; -import javax.swing.event.UndoableEditListener; - -/** - * A helper class for supporting {@link - * javax.swing.event.UndoableEditListener}. - * - * @author Andrew Selkirk (aselkirk@sympatico.ca) - * @author Sascha Brawer (brawer@dandelis.ch) - */ -public class UndoableEditSupport -{ - /** - * The number of times that {@link #beginUpdate()} has been called - * without a matching call to {@link #endUpdate()}. - */ - protected int updateLevel; - - - /** - * compoundEdit - */ - protected CompoundEdit compoundEdit; - - - /** - * The currently registered listeners. - */ - protected Vector listeners = new Vector(); - - - /** - * The source of the broadcast UndoableEditEvents. - */ - protected Object realSource; - - - /** - * Constructs a new helper for broadcasting UndoableEditEvents. The - * events will indicate the newly constructed - * <code>UndoableEditSupport</code> instance as their source. - * - * @see #UndoableEditSupport(java.lang.Object) - */ - public UndoableEditSupport() - { - realSource = this; - } - - - /** - * Constructs a new helper for broadcasting UndoableEditEvents. - * - * @param realSource the source of the UndoableEditEvents that will - * be broadcast by this helper. If <code>realSource</code> is - * <code>null</code>, the events will indicate the newly constructed - * <code>UndoableEditSupport</code> instance as their source. - */ - public UndoableEditSupport(Object realSource) - { - if (realSource == null) - realSource = this; - this.realSource = realSource; - } - - - /** - * Returns a string representation of this object that may be useful - * for debugging. - */ - public String toString() - { - // Note that often, this.realSource == this. Therefore, dumping - // realSource without additional checks may lead to infinite - // recursion. See Classpath bug #7119. - return super.toString() + " updateLevel: " + updateLevel - + " listeners: " + listeners + " compoundEdit: " + compoundEdit; - } - - - /** - * Registers a listener. - * - * @param val the listener to be added. - */ - public synchronized void addUndoableEditListener(UndoableEditListener val) - { - listeners.add(val); - } - - - /** - * Unregisters a listener. - * @param val the listener to be removed. - */ - public synchronized void removeUndoableEditListener(UndoableEditListener val) - { - listeners.removeElement(val); - } - - - /** - * Returns an array containing the currently registered listeners. - */ - public synchronized UndoableEditListener[] getUndoableEditListeners() - { - UndoableEditListener[] result = new UndoableEditListener[listeners.size()]; - return (UndoableEditListener[]) listeners.toArray(result); - } - - - /** - * Notifies all registered listeners that an {@link - * UndoableEditEvent} has occured. - * - * <p><b>Lack of Thread Safety:</b> It is <em>not</em> safe to call - * this method from concurrent threads, unless the call is protected - * by a synchronization on this <code>UndoableEditSupport</code> - * instance. - * - * @param edit the edit action to be posted. - */ - protected void _postEdit(UndoableEdit edit) - { - UndoableEditEvent event; - Iterator iter; - - // Do nothing if we have no listeners. - if (listeners.isEmpty()) - return; - - event = new UndoableEditEvent(realSource, edit); - - // We clone the vector because this allows listeners to register - // or unregister listeners in their undoableEditHappened method. - // Otherwise, this would throw exceptions (in the case of - // Iterator, a java.util.ConcurrentModificationException; in the - // case of a direct loop over the Vector elements, some - // index-out-of-bounds exception). - iter = ((Vector) listeners.clone()).iterator(); - while (iter.hasNext()) - ((UndoableEditListener) iter.next()).undoableEditHappened(event); - } - - - /** - * If {@link #beginEdit} has been called (so that the current - * update level is greater than zero), adds the specified edit - * to {@link #compoundEdit}. Otherwise, notify listeners of the - * edit by calling {@link #_postEdit(UndoableEdit)}. - * - * <p><b>Thread Safety:</b> It is safe to call this method from any - * thread without external synchronization. - * - * @param edit the edit action to be posted. - */ - public synchronized void postEdit(UndoableEdit edit) - { - if (compoundEdit != null) - compoundEdit.addEdit(edit); - else - _postEdit(edit); - } - - - /** - * Returns the current update level. - */ - public int getUpdateLevel() - { - return updateLevel; - } - - - /** - * Starts a (possibly nested) update session. If the current update - * level is zero, {@link #compoundEdit} is set to the result of the - * {@link #createCompoundEdit} method. In any case, the update level - * is increased by one. - * - * <p><b>Thread Safety:</b> It is safe to call this method from any - * thread without external synchronization. - */ - public synchronized void beginUpdate() - { - if (compoundEdit == null) - compoundEdit = createCompoundEdit(); - ++updateLevel; - } - - - /** - * Creates a new instance of {@link #CompoundEdit}. Called by {@link - * #beginUpdate}. If a subclass wants {@link #beginUpdate} to work - * on a specific {@link #compoundEdit}, it should override this - * method. - * - * @returns a newly created instance of {@link #CompoundEdit}. - */ - protected CompoundEdit createCompoundEdit() - { - return new CompoundEdit(); - } - - - /** - * Ends an update session. If the terminated session was the - * outermost session, {@link #compoundEdit} will receive an - * <code>end</code> message, and {@link #_postEdit} gets called in - * order to notify any listeners. Finally, the - * <code>compoundEdit</code> is discarded. - * - * <p><b>Thread Safety:</b> It is safe to call this method from any - * thread without external synchronization. - */ - public synchronized void endUpdate() - { - if (updateLevel == 0) - throw new IllegalStateException(); - - if (--updateLevel > 0) - return; - - compoundEdit.end(); - _postEdit(compoundEdit); - compoundEdit = null; - } -} |
