/*******************************************************************************
* Copyright (c) 2004, 2005 Elias Volanakis 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:
�*����Elias Volanakis - initial API and implementation
�*******************************************************************************/
package org.asem.eclipse.mii.model.commands;
import java.util.Iterator;
import java.util.List;
import org.asem.eclipse.mii.model.abs.AbstractModelShape;
import org.asem.eclipse.mii.model.abs.Connection;
import org.asem.eclipse.mii.model.abs.ShapesFactory;
import org.asem.eclipse.mii.model.shapes.ShapesDiagram;
import org.eclipse.gef.commands.Command;
/**
* A command to remove a shape from its parent. The command can be undone or redone.
*
* @author Elias Volanakis
*/
@SuppressWarnings("rawtypes")
public class ShapeDeleteCommand extends Command {
/** Shape to remove. */
private final AbstractModelShape child;
/** ShapeDiagram to remove from. */
private final ShapesDiagram parent;
/** Holds a copy of the outgoing connections of child. */
private List sourceConnections;
/** Holds a copy of the incoming connections of child. */
private List targetConnections;
/** True, if child was removed from its parent. */
private boolean wasRemoved;
/**
* Create a command that will remove the shape from its parent.
*
* @param parent
* the ShapesDiagram containing the child
* @param child
* the Shape to remove
* @throws IllegalArgumentException
* if any parameter is null
*/
public ShapeDeleteCommand(ShapesDiagram parent, AbstractModelShape child) {
if (parent == null || child == null) {
throw new IllegalArgumentException();
}
setLabel("shape deletion");
this.parent = parent;
this.child = child;
}
/**
* Reconnects a List of Connections with their previous endpoints.
*
* @param connections
* a non-null List of connections
*/
private void addConnections(List connections) {
for (Iterator iter = connections.iterator(); iter.hasNext();) {
Connection conn = (Connection) iter.next();
conn.reconnect();
}
}
/*
* (non-Javadoc)
*
* @see org.eclipse.gef.commands.Command#canUndo()
*/
public boolean canUndo() {
return wasRemoved;
}
/*
* (non-Javadoc)
*
* @see org.eclipse.gef.commands.Command#execute()
*/
public void execute() {
// store a copy of incoming & outgoing connections before proceeding
sourceConnections = child.getSourceConnections();
targetConnections = child.getTargetConnections();
redo();
}
/*
* (non-Javadoc)
*
* @see org.eclipse.gef.commands.Command#redo()
*/
public void redo() {
// remove from ShapesFactory
ShapesFactory.getInstance(child.getClass()).remove(child);
// remove the child and disconnect its connections
wasRemoved = parent.removeChild(child);
if (wasRemoved) {
removeConnections(sourceConnections);
removeConnections(targetConnections);
}
}
/**
* Disconnects a List of Connections from their endpoints.
*
* @param connections
* a non-null List of connections
*/
private void removeConnections(List connections) {
for (Iterator iter = connections.iterator(); iter.hasNext();) {
Connection conn = (Connection) iter.next();
conn.disconnect();
}
}
/*
* (non-Javadoc)
*
* @see org.eclipse.gef.commands.Command#undo()
*/
public void undo() {
// add the child and reconnect its connections
if (parent.addChild(child)) {
addConnections(sourceConnections);
addConnections(targetConnections);
}
}
}