--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dwtx/core/commands/operations/AbstractOperation.d	Wed Mar 26 00:57:19 2008 +0100
@@ -0,0 +1,219 @@
+/*******************************************************************************
+ * Copyright (c) 2005, 2006 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.core.commands.operations.AbstractOperation;
+
+import tango.util.collection.ArraySeq;
+import tango.util.collection.model.Seq;
+
+import dwtx.core.commands.ExecutionException;
+import dwtx.core.runtime.Assert;
+import dwtx.core.runtime.IAdaptable;
+import dwtx.core.runtime.IProgressMonitor;
+import dwtx.core.runtime.IStatus;
+
+import dwtx.core.commands.operations.IUndoableOperation;
+import dwtx.core.commands.operations.IUndoContext;
+
+import dwt.dwthelper.utils;
+static import tango.text.Text;
+alias tango.text.Text.Text!(char) StringBuffer;
+
+/**
+ * <p>
+ * Abstract implementation for an undoable operation. At a minimum, subclasses
+ * should implement behavior for
+ * {@link IUndoableOperation#execute(dwtx.core.runtime.IProgressMonitor, dwtx.core.runtime.IAdaptable)},
+ * {@link IUndoableOperation#redo(dwtx.core.runtime.IProgressMonitor, dwtx.core.runtime.IAdaptable)},
+ * and
+ * {@link IUndoableOperation#undo(dwtx.core.runtime.IProgressMonitor, dwtx.core.runtime.IAdaptable)}.
+ * </p>
+ *
+ * @see dwtx.core.commands.operations.IUndoableOperation
+ *
+ * @since 3.1
+ */
+public abstract class AbstractOperation : IUndoableOperation {
+    Seq!(IUndoContext) contexts;
+
+    private String label = ""; //$NON-NLS-1$
+
+    /**
+     * Construct an operation that has the specified label.
+     *
+     * @param label
+     *            the label to be used for the operation.
+     */
+    public this(String label) {
+        this.label = label;
+        contexts = new ArraySeq!(IUndoContext);
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see dwtx.core.commands.operations.IUndoableOperation#addContext(dwtx.core.commands.operations.IUndoContext)
+     *
+     * <p> Subclasses may override this method. </p>
+     */
+    public void addContext(IUndoContext context) {
+        if (!contexts.contains(context)) {
+            contexts.append(context);
+        }
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see dwtx.core.commands.operations.IUndoableOperation#canExecute()
+     *      <p> Default implementation. Subclasses may override this method.
+     *      </p>
+     *
+     */
+    public bool canExecute() {
+        return true;
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see dwtx.core.commands.operations.IUndoableOperation#canRedo()
+     *      <p> Default implementation. Subclasses may override this method.
+     *      </p>
+     */
+    public bool canRedo() {
+        return true;
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see dwtx.core.commands.operations.IUndoableOperation#canUndo()
+     *      <p> Default implementation. Subclasses may override this method.
+     *      </p>
+     */
+    public bool canUndo() {
+        return true;
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see dwtx.core.commands.operations.IUndoableOperation#dispose()
+     *      <p> Default implementation. Subclasses may override this method.
+     *      </p>
+     */
+    public void dispose() {
+        // nothing to dispose.
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see dwtx.core.commands.operations.IUndoableOperation#execute(dwtx.core.runtime.IProgressMonitor,
+     *      dwtx.core.runtime.IAdaptable)
+     */
+    public abstract IStatus execute(IProgressMonitor monitor, IAdaptable info);
+
+    public final IUndoContext[] getContexts() {
+        return contexts.toArray();
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see dwtx.core.commands.operations.IUndoableOperation#getLabel()
+     *      <p> Default implementation. Subclasses may override this method.
+     *      </p>
+     */
+    public String getLabel() {
+        return label;
+    }
+
+    /**
+     * Set the label of the operation to the specified name.
+     *
+     * @param name
+     *            the string to be used for the label.
+     */
+    public void setLabel(String name) {
+        label = name;
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see dwtx.core.commands.operations.IUndoableOperation#hasContext(dwtx.core.commands.operations.IUndoContext)
+     */
+    public final bool hasContext(IUndoContext context) {
+        Assert.isNotNull(cast(Object)context);
+        for (int i = 0; i < contexts.size(); i++) {
+            IUndoContext otherContext = contexts.get(i);
+            // have to check both ways because one context may be more general
+            // in
+            // its matching rules than another.
+            if (context.matches(otherContext) || otherContext.matches(context)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see dwtx.core.commands.operations.IUndoableOperation#redo(dwtx.core.runtime.IProgressMonitor,
+     *      dwtx.core.runtime.IAdaptable)
+     */
+    public abstract IStatus redo(IProgressMonitor monitor, IAdaptable info);
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see dwtx.core.commands.operations.IUndoableOperation#removeContext(dwtx.core.commands.operations.IUndoContext)
+     *      <p> Default implementation. Subclasses may override this method.
+     *      </p>
+     */
+
+    public void removeContext(IUndoContext context) {
+        contexts.remove(context);
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see dwtx.core.commands.operations.IUndoableOperation#undo(dwtx.core.runtime.IProgressMonitor,
+     *      dwtx.core.runtime.IAdaptable)
+     */
+    public abstract IStatus undo(IProgressMonitor monitor, IAdaptable info);
+
+    /**
+     * The string representation of this operation. Used for debugging purposes
+     * only. This string should not be shown to an end user.
+     *
+     * @return The string representation.
+     */
+    public String toString() {
+        StringBuffer stringBuffer = new StringBuffer();
+        stringBuffer.append(getLabel());
+        stringBuffer.append("("); //$NON-NLS-1$
+        IUndoContext[] contexts = getContexts();
+        for (int i = 0; i < contexts.length; i++) {
+            stringBuffer.append((cast(Object)contexts[i]).toString());
+            if (i !is contexts.length - 1) {
+                stringBuffer.append(',');
+            }
+        }
+        stringBuffer.append(')');
+        return stringBuffer.toString();
+    }
+}