Java tutorial
/* =========================================================== * JFreeChart : a free chart library for the Java(tm) platform * =========================================================== * * (C) Copyright 2000-2013, by Object Refinery Limited and Contributors. * * Project Info: http://www.jfree.org/jfreechart/index.html * * This library is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or * (at your option) any later version. * * This library is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public * License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, * USA. * * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. * Other names may be trademarks of their respective owners.] * * --------------------------------------- * AbstractCategoryItemLabelGenerator.java * --------------------------------------- * (C) Copyright 2005-2013, by Object Refinery Limited. * * Original Author: David Gilbert (for Object Refinery Limited); * Contributor(s): -; * * Changes * ------- * 11-May-2004 : Version 1, distilled from StandardCategoryLabelGenerator (DG); * 31-Jan-2005 : Added methods to return row and column labels (DG); * 17-May-2005 : Added percentage to item array (DG); * ------------- JFREECHART 1.0.x --------------------------------------------- * 03-May-2006 : Added new constructor (DG); * 23-Nov-2007 : Implemented hashCode() (DG); * 02-Jul-2013 : Use ParamChecks (DG); * */ package org.jfree.chart.labels; import java.io.Serializable; import java.text.DateFormat; import java.text.MessageFormat; import java.text.NumberFormat; import org.jfree.chart.HashUtilities; import org.jfree.chart.util.ParamChecks; import org.jfree.data.DataUtilities; import org.jfree.data.category.CategoryDataset; import org.jfree.util.ObjectUtilities; import org.jfree.util.PublicCloneable; /** * A base class that can be used to create a label or tooltip generator that * can be assigned to a * {@link org.jfree.chart.renderer.category.CategoryItemRenderer}. */ public abstract class AbstractCategoryItemLabelGenerator implements PublicCloneable, Cloneable, Serializable { /** For serialization. */ private static final long serialVersionUID = -7108591260223293197L; /** * The label format string used by a <code>MessageFormat</code> object to * combine the standard items: {0} = series name, {1} = category, * {2} = value, {3} = value as a percentage of the column total. */ private String labelFormat; /** The string used to represent a null value. */ private String nullValueString; /** * A number formatter used to preformat the value before it is passed to * the MessageFormat object. */ private NumberFormat numberFormat; /** * A date formatter used to preformat the value before it is passed to the * MessageFormat object. */ private DateFormat dateFormat; /** * A number formatter used to preformat the percentage value before it is * passed to the MessageFormat object. */ private NumberFormat percentFormat; /** * Creates a label generator with the specified number formatter. * * @param labelFormat the label format string (<code>null</code> not * permitted). * @param formatter the number formatter (<code>null</code> not permitted). */ protected AbstractCategoryItemLabelGenerator(String labelFormat, NumberFormat formatter) { this(labelFormat, formatter, NumberFormat.getPercentInstance()); } /** * Creates a label generator with the specified number formatter. * * @param labelFormat the label format string (<code>null</code> not * permitted). * @param formatter the number formatter (<code>null</code> not permitted). * @param percentFormatter the percent formatter (<code>null</code> not * permitted). * * @since 1.0.2 */ protected AbstractCategoryItemLabelGenerator(String labelFormat, NumberFormat formatter, NumberFormat percentFormatter) { ParamChecks.nullNotPermitted(labelFormat, "labelFormat"); ParamChecks.nullNotPermitted(formatter, "formatter"); ParamChecks.nullNotPermitted(percentFormatter, "percentFormatter"); this.labelFormat = labelFormat; this.numberFormat = formatter; this.percentFormat = percentFormatter; this.dateFormat = null; this.nullValueString = "-"; } /** * Creates a label generator with the specified date formatter. * * @param labelFormat the label format string (<code>null</code> not * permitted). * @param formatter the date formatter (<code>null</code> not permitted). */ protected AbstractCategoryItemLabelGenerator(String labelFormat, DateFormat formatter) { ParamChecks.nullNotPermitted(labelFormat, "labelFormat"); ParamChecks.nullNotPermitted(formatter, "formatter"); this.labelFormat = labelFormat; this.numberFormat = null; this.percentFormat = NumberFormat.getPercentInstance(); this.dateFormat = formatter; this.nullValueString = "-"; } /** * Generates a label for the specified row. * * @param dataset the dataset (<code>null</code> not permitted). * @param row the row index (zero-based). * * @return The label. */ public String generateRowLabel(CategoryDataset dataset, int row) { return dataset.getRowKey(row).toString(); } /** * Generates a label for the specified row. * * @param dataset the dataset (<code>null</code> not permitted). * @param column the column index (zero-based). * * @return The label. */ public String generateColumnLabel(CategoryDataset dataset, int column) { return dataset.getColumnKey(column).toString(); } /** * Returns the label format string. * * @return The label format string (never <code>null</code>). */ public String getLabelFormat() { return this.labelFormat; } /** * Returns the number formatter. * * @return The number formatter (possibly <code>null</code>). */ public NumberFormat getNumberFormat() { return this.numberFormat; } /** * Returns the date formatter. * * @return The date formatter (possibly <code>null</code>). */ public DateFormat getDateFormat() { return this.dateFormat; } /** * Generates a for the specified item. * * @param dataset the dataset (<code>null</code> not permitted). * @param row the row index (zero-based). * @param column the column index (zero-based). * * @return The label (possibly <code>null</code>). */ protected String generateLabelString(CategoryDataset dataset, int row, int column) { ParamChecks.nullNotPermitted(dataset, "dataset"); String result; Object[] items = createItemArray(dataset, row, column); result = MessageFormat.format(this.labelFormat, items); return result; } /** * Creates the array of items that can be passed to the * {@link MessageFormat} class for creating labels. * * @param dataset the dataset (<code>null</code> not permitted). * @param row the row index (zero-based). * @param column the column index (zero-based). * * @return The items (never <code>null</code>). */ protected Object[] createItemArray(CategoryDataset dataset, int row, int column) { Object[] result = new Object[4]; result[0] = dataset.getRowKey(row).toString(); result[1] = dataset.getColumnKey(column).toString(); Number value = dataset.getValue(row, column); if (value != null) { if (this.numberFormat != null) { result[2] = this.numberFormat.format(value); } else if (this.dateFormat != null) { result[2] = this.dateFormat.format(value); } } else { result[2] = this.nullValueString; } if (value != null) { double total = DataUtilities.calculateColumnTotal(dataset, column); double percent = value.doubleValue() / total; result[3] = this.percentFormat.format(percent); } return result; } /** * Tests this object for equality with an arbitrary object. * * @param obj the other object (<code>null</code> permitted). * * @return A boolean. */ @Override public boolean equals(Object obj) { if (obj == this) { return true; } if (!(obj instanceof AbstractCategoryItemLabelGenerator)) { return false; } AbstractCategoryItemLabelGenerator that = (AbstractCategoryItemLabelGenerator) obj; if (!this.labelFormat.equals(that.labelFormat)) { return false; } if (!ObjectUtilities.equal(this.dateFormat, that.dateFormat)) { return false; } if (!ObjectUtilities.equal(this.numberFormat, that.numberFormat)) { return false; } return true; } /** * Returns a hash code for this instance. * * @return A hash code. */ @Override public int hashCode() { int result = 127; result = HashUtilities.hashCode(result, this.labelFormat); result = HashUtilities.hashCode(result, this.nullValueString); result = HashUtilities.hashCode(result, this.dateFormat); result = HashUtilities.hashCode(result, this.numberFormat); result = HashUtilities.hashCode(result, this.percentFormat); return result; } /** * Returns an independent copy of the generator. * * @return A clone. * * @throws CloneNotSupportedException should not happen. */ @Override public Object clone() throws CloneNotSupportedException { AbstractCategoryItemLabelGenerator clone = (AbstractCategoryItemLabelGenerator) super.clone(); if (this.numberFormat != null) { clone.numberFormat = (NumberFormat) this.numberFormat.clone(); } if (this.dateFormat != null) { clone.dateFormat = (DateFormat) this.dateFormat.clone(); } return clone; } }