/*
* Copyright (C) 2012 Jason Gedge <http://www.gedge.ca>
*
* This file is part of the OpGraph project.
*
* This program 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 3 of the License, or
* (at your option) any later version.
*
* This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
package ca.gedge.opgraph.app.edits.graph;
import javax.swing.undo.AbstractUndoableEdit;
import javax.swing.undo.CannotRedoException;
import javax.swing.undo.CannotUndoException;
import ca.gedge.opgraph.OpLink;
import ca.gedge.opgraph.OpGraph;
import ca.gedge.opgraph.dag.CycleDetectedException;
import ca.gedge.opgraph.dag.VertexNotFoundException;
/**
* Removes a link between two fields.
*/
public class RemoveLinkEdit extends AbstractUndoableEdit {
/** The graph to which this edit was applied */
private OpGraph graph;
/** The link that was removed */
private final OpLink link;
/**
* Constructs an edit that removes a given link from a canvas model.
*
* @param graph the graph to which this edit will be applied
* @param link the link to add
*/
public RemoveLinkEdit(OpGraph graph, OpLink link) {
this.graph = graph;
this.link = link;
perform();
}
/**
* Performs this edit.
*/
private void perform() {
graph.remove(link);
}
//
// AbstractUndoableEdit
//
@Override
public String getPresentationName() {
return "Remove Link";
}
@Override
public void redo() throws CannotRedoException {
super.redo();
perform();
}
@Override
public void undo() throws CannotUndoException {
super.undo();
try {
graph.add(link);
} catch(VertexNotFoundException exc) {
throw new CannotUndoException();
} catch(CycleDetectedException exc) {
throw new CannotUndoException();
}
}
}