    001/* ===========================================================
    002 * Orson Charts : a 3D chart library for the Java(tm) platform
    003 * ===========================================================
    004 *
    005 * (C)opyright 2013-2016, by Object Refinery Limited.  All rights reserved.
    006 *
    007 * http://www.object-refinery.com/orsoncharts/index.html
    008 *
    009 * This program is free software: you can redistribute it and/or modify
    010 * it under the terms of the GNU General Public License as published by
    011 * the Free Software Foundation, either version 3 of the License, or
    012 * (at your option) any later version.
    013 *
    014 * This program is distributed in the hope that it will be useful,
    015 * but WITHOUT ANY WARRANTY; without even the implied warranty of
    016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    017 * GNU General Public License for more details.
    018 *
    019 * You should have received a copy of the GNU General Public License
    020 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
    021 *
    022 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
    023 * Other names may be trademarks of their respective owners.]
    024 *
    025 * If you do not wish to be bound by the terms of the GPL, an alternative
    026 * commercial license can be purchased.  For details, please see visit the
    027 * Orson Charts home page:
    028 *
    029 * http://www.object-refinery.com/orsoncharts/index.html
    030 *
    031 */
    032
    033package com.orsoncharts.label;
    034
    035import java.io.Serializable;
    036import java.util.Formatter;
    037
    038import com.orsoncharts.data.DataUtils;
    039import com.orsoncharts.data.PieDataset3D;
    040import com.orsoncharts.util.ArgChecks;
    041
    042/**
    043 * A default implementation of the {@link PieLabelGenerator} interface.  The
    044 * implementation uses a {@link java.util.Formatter} instance to generate
    045 * the labels.  Three values are passed to the formatter: (1) the key for
    046 * the current pie section, (2) the data value for the section (as a
    047 * {@code Double}, possibly {@code null}) and (3) the calculated
    048 * percentage value (as a {@code Double}, {@code Double.NaN} if the
    049 * value is {@code null}).
    050 * <br><br>
    051 * NOTE: This class is serializable, but the serialization format is subject
    052 * to change in future releases and should not be relied upon for persisting
    053 * instances of this class.
    054 *
    055 * @since 1.2
    056 */
    057@SuppressWarnings("serial")
    058public class StandardPieLabelGenerator implements PieLabelGenerator,
    059        Serializable {
    060
    061    /**
    062     * A template string that will show the section key only.
    063     *
    064     * @since 1.2
    065     */
    066    public static final String KEY_ONLY_TEMPLATE = "%s";
    067
    068    /**
    069     * A template string that will show the section key followed by the
    070     * percentage in brackets (with zero decimal places).
    071     *
    072     * @since 1.2
    073     */
    074    public static final String PERCENT_TEMPLATE = "%s (%3$,.0f%%)";
    075
    076    /**
    077     * A template string that will show the section key followed by the
    078     * percentage in brackets (with two decimal places precision).
    079     *
    080     * @since 1.2
    081     */
    082    public static final String PERCENT_TEMPLATE_2DP = "%s (%3$,.2f%%)";
    083
    084    /**
    085     * A template string that will show the section key followed by the
    086     * value in brackets (with zero decimal places precision).
    087     *
    088     * @since 1.2
    089     */
    090    public static final String VALUE_TEMPLATE = "%s (%2$,.0f)";
    091
    092    /**
    093     * A template string that will show the section key followed by the
    094     * value in brackets (with two decimal places precision).
    095     *
    096     * @since 1.2
    097     */
    098    public static final String VALUE_TEMPLATE_2DP = "%s (%2$,.2f)";
    099
    100    /**
    101     * The default template string (used in the default constructor, it is
    102     * equivalent to {@link #PERCENT_TEMPLATE}).
    103     *
    104     * @since 1.2
    105     */
    106    public static final String DEFAULT_TEMPLATE = PERCENT_TEMPLATE;
    107
    108    /** The label template. */
    109    private String template;
    110
    111    /**
    112     * The default constructor, uses {@link #DEFAULT_TEMPLATE} for the
    113     * template string.
    114     */
    115    public StandardPieLabelGenerator() {
    116        this(DEFAULT_TEMPLATE);
    117    }
    118
    119    /**
    120     * Creates a new instance with the specified template string (which will
    121     * be passed to a {@code java.util.Formatter} instance when generating
    122     * labels).  See the class description for an explanation of the values
    123     * that are available for use in the template string.
    124     *
    125     * @param template  the template ({@code null} not permitted).
    126     */
    127    public StandardPieLabelGenerator(String template) {
    128        ArgChecks.nullNotPermitted(template, "template");
    129        this.template = template;
    130    }
    131
    132    /**
    133     * Generates the label for one section in a pie chart.
    134     *
    135     * @param dataset  the dataset ({@code null} not permitted).
    136     * @param key  the key ({@code null} not permitted).
    137     *
    138     * @return The label (never {@code null} for this implementation).
    139     */
    140    @Override
    141    public String generateLabel(PieDataset3D dataset, Comparable<?> key) {
    142        ArgChecks.nullNotPermitted(dataset, "dataset");
    143        ArgChecks.nullNotPermitted(key, "key");
    144        Formatter formatter = new Formatter(new StringBuilder());
    145        Number value = dataset.getValue(key);
    146        Number percent = Double.NaN;
    147        if (value != null) {
    148            double total = DataUtils.total(dataset);
    149            percent = Double.valueOf(100.0 * value.doubleValue() / total);
    150        }
    151        formatter.format(this.template, key, value, percent);
    152        String result = formatter.toString();
    153        formatter.close();
    154        return result;
    155    }
    156
    157    /**
    158     * Tests this label generator for equality with an arbitrary object.
    159     *
    160     * @param obj  the object ({@code null} permitted).
    161     *
    162     * @return A boolean.
    163     */
    164    @Override
    165    public boolean equals(Object obj) {
    166        if (obj == this) {
    167            return true;
    168        }
    169        if (!(obj instanceof StandardPieLabelGenerator)) {
    170            return false;
    171        }
    172        StandardPieLabelGenerator that = (StandardPieLabelGenerator) obj;
    173        if (!this.template.equals(that.template)) {
    174            return false;
    175        }
    176        return true;
    177    }
    178
    179    @Override
    180    public int hashCode() {
    181        return this.template.hashCode();
    182    }
    183
    184}