001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-present, by David Gilbert 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
029package org.jfree.chart.ui;
030
031import java.io.ObjectStreamException;
032import java.io.Serializable;
033
034/**
035 * An enumeration of the horizontal alignment types ({@code LEFT}, 
036 * {@code RIGHT} and {@code CENTER}).
037 */
038public final class HorizontalAlignment implements Serializable {
039
040    /** For serialization. */
041    private static final long serialVersionUID = -8249740987565309567L;
042    
043    /** Left alignment. */
044    public static final HorizontalAlignment LEFT 
045        = new HorizontalAlignment("HorizontalAlignment.LEFT");
046
047    /** Right alignment. */
048    public static final HorizontalAlignment RIGHT 
049        = new HorizontalAlignment("HorizontalAlignment.RIGHT");
050
051    /** Center alignment. */
052    public static final HorizontalAlignment CENTER 
053        = new HorizontalAlignment("HorizontalAlignment.CENTER");
054
055    /** The name. */
056    private String name;
057
058    /**
059     * Private constructor.
060     *
061     * @param name  the name.
062     */
063    private HorizontalAlignment(String name) {
064        this.name = name;
065    }
066
067    /**
068     * Returns a string representing the object.
069     *
070     * @return The string.
071     */
072    @Override
073    public String toString() {
074        return this.name;
075    }
076
077    /**
078     * Returns {@code true} if this object is equal to the specified 
079     * object, and {@code false} otherwise.
080     *
081     * @param obj  the object ({@code null} permitted).
082     *
083     * @return A boolean.
084     */
085    @Override
086    public boolean equals(Object obj) {
087        if (this == obj) {
088            return true;
089        }
090        if (!(obj instanceof HorizontalAlignment)) {
091            return false;
092        }
093        final HorizontalAlignment that = (HorizontalAlignment) obj;
094        if (!this.name.equals(that.name)) {
095            return false;
096        }
097        return true;
098    }
099
100    /**
101     * Returns a hash code value for the object.
102     *
103     * @return The hashcode
104     */
105    @Override
106    public int hashCode() {
107        return this.name.hashCode();
108    }
109
110    /**
111     * Ensures that serialization returns the unique instances.
112     * 
113     * @return The object.
114     * 
115     * @throws ObjectStreamException if there is a problem.
116     */
117    private Object readResolve() throws ObjectStreamException {
118        HorizontalAlignment result = null;
119        if (this.equals(HorizontalAlignment.LEFT)) {
120            result = HorizontalAlignment.LEFT;
121        }
122        else if (this.equals(HorizontalAlignment.RIGHT)) {
123            result = HorizontalAlignment.RIGHT;
124        }
125        else if (this.equals(HorizontalAlignment.CENTER)) {
126            result = HorizontalAlignment.CENTER;
127        }
128        return result;
129    }
130    
131}