--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dwtx/text/edits/UndoEdit.d	Sat Aug 23 19:10:48 2008 +0200
@@ -0,0 +1,111 @@
+/*******************************************************************************
+ * Copyright (c) 2000, 2008 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ * Port to the D programming language:
+ *     Frank Benoit <benoit@tionex.de>
+ *******************************************************************************/
+module dwtx.text.edits.UndoEdit;
+
+import dwt.dwthelper.utils;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import dwtx.jface.text.BadLocationException;
+import dwtx.jface.text.IDocument;
+
+
+/**
+ * This class encapsulates the reverse changes of an executed text
+ * edit tree. To apply an undo memento to a document use method
+ * <code>apply(IDocument)</code>.
+ * <p>
+ * Clients can't add additional children to an undo edit nor can they
+ * add an undo edit as a child to another edit. Doing so results in
+ * both cases in a <code>MalformedTreeException<code>.
+ *
+ * @since 3.0
+ * @noinstantiate This class is not intended to be instantiated by clients.
+ */
+public final class UndoEdit : TextEdit {
+
+    UndoEdit() {
+        super(0, Integer.MAX_VALUE);
+    }
+
+    private UndoEdit(UndoEdit other) {
+        super(other);
+    }
+
+    /*
+     * @see dwtx.text.edits.TextEdit#internalAdd(dwtx.text.edits.TextEdit)
+     */
+    void internalAdd(TextEdit child) throws MalformedTreeException {
+        throw new MalformedTreeException(null, this, TextEditMessages.getString("UndoEdit.no_children")); //$NON-NLS-1$
+    }
+
+    /*
+     * @see dwtx.text.edits.MultiTextEdit#aboutToBeAdded(dwtx.text.edits.TextEdit)
+     */
+    void aboutToBeAdded(TextEdit parent) {
+        throw new MalformedTreeException(parent, this, TextEditMessages.getString("UndoEdit.can_not_be_added")); //$NON-NLS-1$
+    }
+
+    UndoEdit dispatchPerformEdits(TextEditProcessor processor) throws BadLocationException {
+        return processor.executeUndo();
+    }
+
+    void dispatchCheckIntegrity(TextEditProcessor processor) throws MalformedTreeException {
+        processor.checkIntegrityUndo();
+    }
+
+    /*
+     * @see dwtx.text.edits.TextEdit#doCopy()
+     */
+    protected TextEdit doCopy() {
+        return new UndoEdit(this);
+    }
+
+    /*
+     * @see TextEdit#accept0
+     */
+    protected void accept0(TextEditVisitor visitor) {
+        bool visitChildren= visitor.visit(this);
+        if (visitChildren) {
+            acceptChildren(visitor);
+        }
+    }
+
+    /*
+     * @see TextEdit#performDocumentUpdating
+     */
+    int performDocumentUpdating(IDocument document) throws BadLocationException {
+        fDelta= 0;
+        return fDelta;
+    }
+
+    void add(ReplaceEdit edit) {
+        List children= internalGetChildren();
+        if (children is null) {
+            children= new ArrayList(2);
+            internalSetChildren(children);
+        }
+        children.add(edit);
+    }
+
+    void defineRegion(int offset, int length) {
+        internalSetOffset(offset);
+        internalSetLength(length);
+    }
+
+    bool deleteChildren() {
+        return false;
+    }
+}
+