    001/* ===========================================================
    002 * JFreeChart : a free chart library for the Java(tm) platform
    003 * ===========================================================
    004 *
    005 * (C) Copyright 2000-2011, 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 * StandardCategorySeriesLabelGenerator.java
    029 * -----------------------------------------
    030 * (C) Copyright 2005-2008, by Object Refinery Limited.
    031 *
    032 * Original Author:  David Gilbert (for Object Refinery Limited);
    033 * Contributor(s):   -;
    034 *
    035 * Changes
    036 * -------
    037 * 20-Apr-2005 : Version 1 (DG);
    038 * ------------- JFREECHART 1.0.x ---------------------------------------------
    039 * 03-May-2006 : Fixed equals() method (bug 1481102) (DG);
    040 * 31-Mar-2008 : Added hashCode() method to appease FindBugs (DG);
    041 *
    042 */
    043
    044package org.jfree.chart.labels;
    045
    046import java.io.Serializable;
    047import java.text.MessageFormat;
    048
    049import org.jfree.chart.HashUtilities;
    050import org.jfree.data.category.CategoryDataset;
    051import org.jfree.util.PublicCloneable;
    052
    053/**
    054 * A standard series label generator for plots that use data from
    055 * a {@link org.jfree.data.category.CategoryDataset}.
    056 */
    057public class StandardCategorySeriesLabelGenerator implements
    058    CategorySeriesLabelGenerator, Cloneable, PublicCloneable, Serializable {
    059
    060    /** For serialization. */
    061    private static final long serialVersionUID = 4630760091523940820L;
    062
    063    /** The default item label format. */
    064    public static final String DEFAULT_LABEL_FORMAT = "{0}";
    065
    066    /** The format pattern. */
    067    private String formatPattern;
    068
    069    /**
    070     * Creates a default series label generator (uses
    071     * {@link #DEFAULT_LABEL_FORMAT}).
    072     */
    073    public StandardCategorySeriesLabelGenerator() {
    074        this(DEFAULT_LABEL_FORMAT);
    075    }
    076
    077    /**
    078     * Creates a new series label generator.
    079     *
    080     * @param format  the format pattern (<code>null</code> not permitted).
    081     */
    082    public StandardCategorySeriesLabelGenerator(String format) {
    083        if (format == null) {
    084            throw new IllegalArgumentException("Null 'format' argument.");
    085        }
    086        this.formatPattern = format;
    087    }
    088
    089    /**
    090     * Generates a label for the specified series.
    091     *
    092     * @param dataset  the dataset (<code>null</code> not permitted).
    093     * @param series  the series.
    094     *
    095     * @return A series label.
    096     */
    097    public String generateLabel(CategoryDataset dataset, int series) {
    098        if (dataset == null) {
    099            throw new IllegalArgumentException("Null 'dataset' argument.");
    100        }
    101        String label = MessageFormat.format(this.formatPattern,
    102                createItemArray(dataset, series));
    103        return label;
    104    }
    105
    106    /**
    107     * Creates the array of items that can be passed to the
    108     * {@link MessageFormat} class for creating labels.
    109     *
    110     * @param dataset  the dataset (<code>null</code> not permitted).
    111     * @param series  the series (zero-based index).
    112     *
    113     * @return The items (never <code>null</code>).
    114     */
    115    protected Object[] createItemArray(CategoryDataset dataset, int series) {
    116        Object[] result = new Object[1];
    117        result[0] = dataset.getRowKey(series).toString();
    118        return result;
    119    }
    120
    121    /**
    122     * Returns an independent copy of the generator.
    123     *
    124     * @return A clone.
    125     *
    126     * @throws CloneNotSupportedException if cloning is not supported.
    127     */
    128    public Object clone() throws CloneNotSupportedException {
    129        return super.clone();
    130    }
    131
    132    /**
    133     * Tests this object for equality with an arbitrary object.
    134     *
    135     * @param obj  the other object (<code>null</code> permitted).
    136     *
    137     * @return A boolean.
    138     */
    139    public boolean equals(Object obj) {
    140        if (obj == this) {
    141            return true;
    142        }
    143        if (!(obj instanceof StandardCategorySeriesLabelGenerator)) {
    144            return false;
    145        }
    146        StandardCategorySeriesLabelGenerator that
    147                = (StandardCategorySeriesLabelGenerator) obj;
    148        if (!this.formatPattern.equals(that.formatPattern)) {
    149            return false;
    150        }
    151        return true;
    152    }
    153
    154    /**
    155     * Returns a hash code for this instance.
    156     *
    157     * @return A hash code.
    158     */
    159    public int hashCode() {
    160        int result = 127;
    161        result = HashUtilities.hashCode(result, this.formatPattern);
    162        return result;
    163    }
    164
    165}