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 * StandardCategorySeriesLabelGenerator.java
029 * -----------------------------------------
030 * (C) Copyright 2005-present, by David Gilbert.
031 *
032 * Original Author:  David Gilbert;
033 * Contributor(s):   Tracy Hiltbrand (equals/hashCode comply with EqualsVerifier);
034 *
035 */
036
037package org.jfree.chart.labels;
038
039import java.io.Serializable;
040import java.text.MessageFormat;
041import java.util.Objects;
042
043import org.jfree.chart.util.Args;
044import org.jfree.chart.util.PublicCloneable;
045import org.jfree.data.category.CategoryDataset;
046
047/**
048 * A standard series label generator for plots that use data from
049 * a {@link org.jfree.data.category.CategoryDataset}.
050 */
051public class StandardCategorySeriesLabelGenerator implements
052    CategorySeriesLabelGenerator, Cloneable, PublicCloneable, Serializable {
053
054    /** For serialization. */
055    private static final long serialVersionUID = 4630760091523940820L;
056
057    /** The default item label format. */
058    public static final String DEFAULT_LABEL_FORMAT = "{0}";
059
060    /** The format pattern. */
061    private String formatPattern;
062
063    /**
064     * Creates a default series label generator (uses
065     * {@link #DEFAULT_LABEL_FORMAT}).
066     */
067    public StandardCategorySeriesLabelGenerator() {
068        this(DEFAULT_LABEL_FORMAT);
069    }
070
071    /**
072     * Creates a new series label generator.
073     *
074     * @param format  the format pattern ({@code null} not permitted).
075     */
076    public StandardCategorySeriesLabelGenerator(String format) {
077        Args.nullNotPermitted(format, "format");
078        this.formatPattern = format;
079    }
080
081    /**
082     * Generates a label for the specified series.
083     *
084     * @param dataset  the dataset ({@code null} not permitted).
085     * @param series  the series.
086     *
087     * @return A series label.
088     */
089    @Override
090    public String generateLabel(CategoryDataset dataset, int series) {
091        Args.nullNotPermitted(dataset, "dataset");
092        String label = MessageFormat.format(this.formatPattern,
093                createItemArray(dataset, series));
094        return label;
095    }
096
097    /**
098     * Creates the array of items that can be passed to the
099     * {@link MessageFormat} class for creating labels.
100     *
101     * @param dataset  the dataset ({@code null} not permitted).
102     * @param series  the series (zero-based index).
103     *
104     * @return The items (never {@code null}).
105     */
106    protected Object[] createItemArray(CategoryDataset dataset, int series) {
107        Object[] result = new Object[1];
108        result[0] = dataset.getRowKey(series).toString();
109        return result;
110    }
111
112    /**
113     * Returns an independent copy of the generator.
114     *
115     * @return A clone.
116     *
117     * @throws CloneNotSupportedException if cloning is not supported.
118     */
119    @Override
120    public Object clone() throws CloneNotSupportedException {
121        return super.clone();
122    }
123
124    /**
125     * Tests this object for equality with an arbitrary object.
126     *
127     * @param obj  the other object ({@code null} permitted).
128     *
129     * @return A boolean.
130     */
131    @Override
132    public boolean equals(Object obj) {
133        if (obj == this) {
134            return true;
135        }
136        if (!(obj instanceof StandardCategorySeriesLabelGenerator)) {
137            return false;
138        }
139        StandardCategorySeriesLabelGenerator that
140                = (StandardCategorySeriesLabelGenerator) obj;
141        if (!Objects.equals(this.formatPattern, that.formatPattern)) {
142            return false;
143        }
144        return true;
145    }
146
147    /**
148     * Returns a hash code for this instance.
149     *
150     * @return A hash code.
151     */
152    @Override
153    public int hashCode() {
154        int hash = 5;
155        hash = 53 * hash + Objects.hashCode(this.formatPattern);
156        return hash;
157    }
158
159}