query/plugins/org.eclipse.acceleo.query.ide.ui/src/org/eclipse/acceleo/query/ide/ui/viewer/ColorManager.java

/*******************************************************************************
 * Copyright (c) 2017 Obeo.
 * 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:
 *     Obeo - initial API and implementation
 *******************************************************************************/
package org.eclipse.acceleo.query.ide.ui.viewer;

import java.util.HashMap;
import java.util.Map;

import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.widgets.Display;

/**
 * {@link Color} manager.
 * 
 * @author <a href="mailto:yvan.lussaud@obeo.fr">Yvan Lussaud</a>
 */
public class ColorManager {

	/**
	 * The {@link RGB} to {@link Color} mapping.
	 */
	protected Map<RGB, Color> colors = new HashMap<RGB, Color>(10);

	/**
	 * Disposes all {@link Color}.
	 */
	public void dispose() {
		for (Color color : colors.values()) {
			color.dispose();
		}
	}

	/**
	 * Gets the {@link Color} corresponding to the given {@link RGB}.
	 * 
	 * @param rgb
	 *            the {@link RGB}
	 * @return the {@link Color} corresponding to the given {@link RGB}
	 */
	public Color getColor(RGB rgb) {
		Color res = colors.get(rgb);

		if (res == null) {
			res = new Color(Display.getCurrent(), rgb);
			colors.put(rgb, res);
		}

		return res;
	}
}