org.eclipse.fmc.blockdiagram.editor/src/org/eclipse/fmc/blockdiagram/editor/features/add/ConnectionAddFeature.java

/*******************************************************************************
 * <copyright>
 *
 * Copyright (c) 2013, 2013 SAP AG.
 * 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:
 *    SAP AG - initial API, implementation and documentation
 *
 * </copyright>
 *
 *******************************************************************************/
package org.eclipse.fmc.blockdiagram.editor.features.add;

import org.eclipse.fmc.blockdiagram.editor.model.ConnectionStyle;
import org.eclipse.graphiti.features.IFeatureProvider;
import org.eclipse.graphiti.features.impl.AbstractAddFeature;
import org.eclipse.graphiti.mm.algorithms.Polygon;
import org.eclipse.graphiti.mm.pictograms.Connection;
import org.eclipse.graphiti.mm.pictograms.ConnectionDecorator;
import org.eclipse.graphiti.mm.pictograms.Diagram;
import org.eclipse.graphiti.services.Graphiti;
import org.eclipse.graphiti.services.IPeService;

/**
 * This is the super class of all add features for connections. It provides
 * functionality to support the different connection styles
 * {@link ConnectionStyle#NORMAL} and {@link ConnectionStyle#MANHATTAN}.
 * 
 * @author Benjamin Schmeling
 * 
 */
public abstract class ConnectionAddFeature extends AbstractAddFeature {

	/**
	 * The connection style.
	 */
	protected ConnectionStyle style;

	/**
	 * Main constructor.
	 * 
	 * @param featureProvider The feature provider.
	 * @param type The style of the connection line.
	 */
	public ConnectionAddFeature(IFeatureProvider featureProvider, ConnectionStyle type) {
		super(featureProvider);
		this.style = type;
	}

	/**
	 * Creates a new Freeform or Manhattan Connection by using the PeService.
	 * 
	 * @return Connection with the style set by the {@linkplain #style}
	 *         attribute.
	 */
	protected Connection createConnection() {
		IPeService pe = Graphiti.getPeService();
		switch (this.style) {
		case NORMAL:
			return pe.createFreeFormConnection(getDiagram());
		case MANHATTAN:
			return pe.createManhattanConnection(getDiagram());
		case COMPOSITE:
			return pe.createCompositeConnection(getDiagram());
		default:
			return pe.createManhattanConnection(getDiagram());
		}
	}

	/**
	 * Creates the arrow decorator for the line.
	 * 
	 * @param diagram
	 *            The diagram the connection belongs to.
	 * @param con
	 *            The connection the decorator should be created for.
	 * @param defaultDirection
	 *            True if default direction should be used (from source to
	 *            target), false otherwise.
	 */
	public static void createArrowDecorator(Diagram diagram, Connection con,
			boolean defaultDirection) {
		ConnectionDecorator deco = Graphiti.getPeService()
				.createConnectionDecorator(con, false,
						defaultDirection ? 1.0 : 0.0, true);
		Polygon poly = Graphiti.getGaService().createPolygon(deco,
				new int[] { -15, 6, 0, 0, -15, -6, -12, 0 });
		poly.setBackground(Graphiti.getGaService()
				.manageColor(diagram, 0, 0, 0));
	}

}