001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2014, by Object Refinery Limited and Contributors.
006 *
007 * Project Info:  http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
022 * USA.
023 *
024 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
025 * Other names may be trademarks of their respective owners.]
026 *
027 * ---------------
028 * ChartHints.java
029 * ---------------
030 * (C) Copyright 2014, by Object Refinery Limited and Contributors.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * Changes
036 * -------
037 * 27-Jun-2014 : Version 1 (DG);
038 *
039 */
040
041package org.jfree.chart;
042
043import java.util.Map;
044
045/**
046 * Special rendering hints that can be used internally by JFreeChart or by
047 * specialised implementations of the {@code Graphics2D} API.  For example,
048 * JFreeSVG's {@code SVGGraphics2D} class, will use the 
049 * {@code KEY_BEGIN_ELEMENT} and {@code KEY_END_ELEMENT} hints to drive the 
050 * output content.
051 * 
052 * @since 1.0.18
053 */
054public final class ChartHints {
055
056    private ChartHints() {
057        // no need to instantiate this    
058    }
059    
060    /**
061     * The key for a hint to signal the beginning of an element.  The value
062     * should be a string containing the element id or, alternatively, a Map 
063     * containing the 'id' (String) and 'ref' (String in JSON format).
064     */
065    public static final Key KEY_BEGIN_ELEMENT = new ChartHints.Key(0);
066    
067    /**
068     * The key for a hint that ends an element.
069     */
070    public static final Key KEY_END_ELEMENT = new ChartHints.Key(1);
071    
072    /**
073     * A key for rendering hints that can be used with JFreeChart (in 
074     * addition to the regular Java2D rendering hints).
075     */
076    public static class Key extends java.awt.RenderingHints.Key {
077
078        /**
079         * Creates a new key.
080         * 
081         * @param privateKey  the private key. 
082         */
083        public Key(int privateKey) {
084            super(privateKey);    
085        }
086    
087        /**
088         * Returns <code>true</code> if <code>val</code> is a value that is
089         * compatible with this key, and <code>false</code> otherwise.
090         * 
091         * @param val  the value.
092         * 
093         * @return A boolean. 
094         */
095        @Override
096        public boolean isCompatibleValue(Object val) {
097            switch (intKey()) {
098                case 0:
099                    return val == null || val instanceof String 
100                            || val instanceof Map;
101                case 1:
102                    return val == null || val instanceof Object;
103                default:
104                    throw new RuntimeException("Not possible!");
105            }
106        }
107    }
108    
109}