Java example source code file (ColorType.java)

This example Java source code file (ColorType.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

background, colortype, focus, foreground, max_count, nullpointerexception, string, text_background, text_foreground, textbackground, textforeground

The ColorType.java Java example source code

/*
 * Copyright (c) 2002, 2005, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package javax.swing.plaf.synth;

/**
 * A typesafe enumeration of colors that can be fetched from a style.
 * <p>
 * Each <code>SynthStyle has a set of ColorTypes that
 * are accessed by way of the
 * {@link SynthStyle#getColor(SynthContext, ColorType)} method.
 * <code>SynthStyle's installDefaults will install
 * the <code>FOREGROUND color
 * as the foreground of
 * the Component, and the <code>BACKGROUND color to the background of
 * the component (assuming that you have not explicitly specified a
 * foreground and background color). Some components
 * support more color based properties, for
 * example <code>JList has the property
 * <code>selectionForeground which will be mapped to
 * <code>FOREGROUND with a component state of
 * <code>SynthConstants.SELECTED.
 * <p>
 * The following example shows a custom <code>SynthStyle that returns
 * a red Color for the <code>DISABLED state, otherwise a black color.
 * <pre>
 * class MyStyle extends SynthStyle {
 *     private Color disabledColor = new ColorUIResource(Color.RED);
 *     private Color color = new ColorUIResource(Color.BLACK);
 *     protected Color getColorForState(SynthContext context, ColorType type){
 *         if (context.getComponentState() == SynthConstants.DISABLED) {
 *             return disabledColor;
 *         }
 *         return color;
 *     }
 * }
 * </pre>
 *
 * @since 1.5
 * @author Scott Violet
 */
public class ColorType {
    /**
     * ColorType for the foreground of a region.
     */
    public static final ColorType FOREGROUND = new ColorType("Foreground");

    /**
     * ColorType for the background of a region.
     */
    public static final ColorType BACKGROUND = new ColorType("Background");

    /**
     * ColorType for the foreground of a region.
     */
    public static final ColorType TEXT_FOREGROUND = new ColorType(
                                       "TextForeground");

    /**
     * ColorType for the background of a region.
     */
    public static final ColorType TEXT_BACKGROUND =new ColorType(
                                       "TextBackground");

    /**
     * ColorType for the focus.
     */
    public static final ColorType FOCUS = new ColorType("Focus");

    /**
     * Maximum number of <code>ColorTypes.
     */
    public static final int MAX_COUNT;

    private static int nextID;

    private String description;
    private int index;

    static {
        MAX_COUNT = Math.max(FOREGROUND.getID(), Math.max(
                                 BACKGROUND.getID(), FOCUS.getID())) + 1;
    }

    /**
     * Creates a new ColorType with the specified description.
     *
     * @param description String description of the ColorType.
     */
    protected ColorType(String description) {
        if (description == null) {
            throw new NullPointerException(
                          "ColorType must have a valid description");
        }
        this.description = description;
        synchronized(ColorType.class) {
            this.index = nextID++;
        }
    }

    /**
     * Returns a unique id, as an integer, for this ColorType.
     *
     * @return a unique id, as an integer, for this ColorType.
     */
    public final int getID() {
        return index;
    }

    /**
     * Returns the textual description of this <code>ColorType.
     * This is the same value that the <code>ColorType was created
     * with.
     *
     * @return the description of the string
     */
    public String toString() {
        return description;
    }
}