Java tutorial
/* =========================================================== * JFreeChart : a free chart library for the Java(tm) platform * =========================================================== * * (C) Copyright 2000-2009, 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. * * [Java is a trademark or registered trademark of Sun Microsystems, Inc. * in the United States and other countries.] * * ---------------------- * DefaultPieDataset.java * ---------------------- * (C) Copyright 2001-2009, by Object Refinery Limited. * * Original Author: David Gilbert (for Object Refinery Limited); * Contributor(s): Sam (oldman); * * Changes * ------- * 17-Nov-2001 : Version 1 (DG); * 22-Jan-2002 : Removed legend methods from dataset implementations (DG); * 07-Apr-2002 : Modified implementation to guarantee data sequence to remain * in the order categories are added (oldman); * 23-Oct-2002 : Added getCategory(int) method and getItemCount() method, in * line with changes to the PieDataset interface (DG); * 04-Feb-2003 : Changed underlying data storage to DefaultKeyedValues (DG); * 04-Mar-2003 : Inserted DefaultKeyedValuesDataset class into hierarchy (DG); * 24-Apr-2003 : Switched places with DefaultKeyedValuesDataset (DG); * 18-Aug-2003 : Implemented Cloneable (DG); * 03-Mar-2005 : Implemented PublicCloneable (DG); * 29-Jun-2005 : Added remove() method (DG); * ------------- JFREECHART 1.0.0 --------------------------------------------- * 31-Jul-2006 : Added a clear() method to clear all values from the * dataset (DG); * 28-Sep-2006 : Added sortByKeys() and sortByValues() methods (DG); * 30-Apr-2007 : Added new insertValues() methods (DG); * 20-Jun-2007 : Removed JCommon dependencies (DG); * 01-Jul-2009 : Now extends AbstractPieDataset (DG); * */ package org.jfree.data.pie; import org.jfree.data.SelectableValue; import java.io.Serializable; import java.util.Collections; import java.util.List; import org.jfree.chart.event.DatasetChangeInfo; import org.jfree.chart.util.PublicCloneable; import org.jfree.chart.util.SortOrder; import org.jfree.data.KeyedObjects; import org.jfree.data.KeyedValues; import org.jfree.data.UnknownKeyException; import org.jfree.data.event.DatasetChangeEvent; /** * A default implementation of the {@link PieDataset} interface. */ public class DefaultPieDataset extends AbstractPieDataset implements PieDataset, PieDatasetSelectionState, Cloneable, PublicCloneable, Serializable { /** For serialization. */ private static final long serialVersionUID = 2904745139106540618L; /** Storage for the data. */ private KeyedObjects data; /** * Constructs a new dataset, initially empty. */ public DefaultPieDataset() { this.data = new KeyedObjects(); setSelectionState(this); } /** * Creates a new dataset by copying data from a {@link KeyedValues} * instance. * * @param data the data (<code>null</code> not permitted). */ public DefaultPieDataset(KeyedValues data) { if (data == null) { throw new IllegalArgumentException("Null 'data' argument."); } this.data = new KeyedObjects(); for (int i = 0; i < data.getItemCount(); i++) { SelectableValue dataItem = new SelectableValue(data.getValue(i)); this.data.addObject(data.getKey(i), dataItem); } } /** * Returns the number of items in the dataset. * * @return The item count. */ public int getItemCount() { return this.data.getItemCount(); } /** * Returns the categories in the dataset. The returned list is * unmodifiable. * * @return The categories in the dataset. */ public List getKeys() { // FIXME: perhaps we should clone the list? return Collections.unmodifiableList(this.data.getKeys()); } /** * Returns the key for the specified item, or <code>null</code>. * * @param item the item index (in the range <code>0</code> to * <code>getItemCount() - 1</code>). * * @return The key, or <code>null</code>. * * @throws IndexOutOfBoundsException if <code>item</code> is not in the * specified range. */ public Comparable getKey(int item) { return this.data.getKey(item); } /** * Returns the index for a key, or -1 if the key is not recognised. * * @param key the key (<code>null</code> not permitted). * * @return The index, or <code>-1</code> if the key is unrecognised. * * @throws IllegalArgumentException if <code>key</code> is * <code>null</code>. */ public int getIndex(Comparable key) { return this.data.getIndex(key); } /** * Returns a value. * * @param item the value index. * * @return The value (possibly <code>null</code>). */ public Number getValue(int item) { Number result = null; if (getItemCount() > item) { SelectableValue dataItem = (SelectableValue) this.data.getObject(item); result = dataItem.getValue(); } return result; } /** * Returns the data value associated with a key. * * @param key the key (<code>null</code> not permitted). * * @return The value (possibly <code>null</code>). * * @throws UnknownKeyException if the key is not recognised. */ public Number getValue(Comparable key) { if (key == null) { throw new IllegalArgumentException("Null 'key' argument."); } SelectableValue dataItem = (SelectableValue) this.data.getObject(key); return dataItem.getValue(); } /** * Sets the data value for a key and sends a {@link DatasetChangeEvent} to * all registered listeners. * * @param key the key (<code>null</code> not permitted). * @param value the value. * * @throws IllegalArgumentException if <code>key</code> is * <code>null</code>. */ public void setValue(Comparable key, Number value) { int index = this.data.getIndex(key); PieDatasetChangeType ct = PieDatasetChangeType.ADD; if (index >= 0) { ct = PieDatasetChangeType.UPDATE; } this.data.setObject(key, new SelectableValue(value)); PieDatasetChangeInfo info = new PieDatasetChangeInfo(ct, index, index); fireDatasetChanged(info); } /** * Sets the data value for a key and sends a {@link DatasetChangeEvent} to * all registered listeners. * * @param key the key (<code>null</code> not permitted). * @param value the value. * * @throws IllegalArgumentException if <code>key</code> is * <code>null</code>. */ public void setValue(Comparable key, double value) { setValue(key, new Double(value)); } /** * Inserts a new value at the specified position in the dataset or, if * there is an existing item with the specified key, updates the value * for that item and moves it to the specified position. After the change * is made, this methods sends a {@link DatasetChangeEvent} to all * registered listeners. * * @param position the position (in the range 0 to getItemCount()). * @param key the key (<code>null</code> not permitted). * @param value the value (<code>null</code> permitted). * * @since 1.0.6 */ public void insertValue(int position, Comparable key, double value) { insertValue(position, key, new Double(value)); } /** * Inserts a new value at the specified position in the dataset or, if * there is an existing item with the specified key, updates the value * for that item and moves it to the specified position. After the change * is made, this method sends a {@link DatasetChangeEvent} to all * registered listeners. * * @param position the position (in the range 0 to getItemCount()). * @param key the key (<code>null</code> not permitted). * @param value the value (<code>null</code> permitted). * * @since 1.0.6 */ public void insertValue(int position, Comparable key, Number value) { this.data.insertValue(position, key, value); PieDatasetChangeType ct = PieDatasetChangeType.ADD; // TODO: unit tests for inserts where key already exists. fireDatasetChanged(new PieDatasetChangeInfo(ct, position, position)); } /** * Removes an item from the dataset and sends a {@link DatasetChangeEvent} * to all registered listeners. * * @param key the key (<code>null</code> not permitted). * * @throws IllegalArgumentException if <code>key</code> is * <code>null</code>. */ public void remove(Comparable key) { int i = getIndex(key); this.data.removeValue(key); PieDatasetChangeType ct = PieDatasetChangeType.REMOVE; fireDatasetChanged(new PieDatasetChangeInfo(ct, i, i)); } /** * Clears all data from this dataset and sends a {@link DatasetChangeEvent} * to all registered listeners (unless the dataset was already empty). * * @since 1.0.2 */ public void clear() { if (getItemCount() > 0) { this.data.clear(); PieDatasetChangeType ct = PieDatasetChangeType.CLEAR; fireDatasetChanged(new PieDatasetChangeInfo(ct, -1, -1)); } } /** * Sorts the dataset's items by key and sends a {@link DatasetChangeEvent} * to all registered listeners. * * @param order the sort order (<code>null</code> not permitted). * * @since 1.0.3 */ public void sortByKeys(SortOrder order) { this.data.sortByKeys(order); PieDatasetChangeType ct = PieDatasetChangeType.UPDATE; fireDatasetChanged(new PieDatasetChangeInfo(ct, 0, getItemCount() - 1)); } /** * Sorts the dataset's items by value and sends a {@link DatasetChangeEvent} * to all registered listeners. * * @param order the sort order (<code>null</code> not permitted). * * @since 1.0.3 */ public void sortByValues(SortOrder order) { this.data.sortByObjects(order); PieDatasetChangeType ct = PieDatasetChangeType.UPDATE; fireDatasetChanged(new PieDatasetChangeInfo(ct, 0, getItemCount() - 1)); } /** * Tests if this object is equal to another. * * @param obj the other object. * * @return A boolean. */ public boolean equals(Object obj) { if (obj == this) { return true; } if (!(obj instanceof PieDataset)) { return false; } PieDataset that = (PieDataset) obj; int count = getItemCount(); if (that.getItemCount() != count) { return false; } for (int i = 0; i < count; i++) { Comparable k1 = getKey(i); Comparable k2 = that.getKey(i); if (!k1.equals(k2)) { return false; } Number v1 = getValue(i); Number v2 = that.getValue(i); if (v1 == null) { if (v2 != null) { return false; } } else { if (!v1.equals(v2)) { return false; } } } return true; } /** * Returns a hash code. * * @return A hash code. */ public int hashCode() { return this.data.hashCode(); } /** * Returns a clone of the dataset. * * @return A clone. * * @throws CloneNotSupportedException This class will not throw this * exception, but subclasses (if any) might. */ public Object clone() throws CloneNotSupportedException { DefaultPieDataset clone = (DefaultPieDataset) super.clone(); clone.data = (KeyedObjects) this.data.clone(); return clone; } public boolean isSelected(Comparable key) { SelectableValue item = (SelectableValue) this.data.getObject(key); return item.isSelected(); } public void setSelected(Comparable key, boolean selected) { setSelected(key, selected, true); } public void setSelected(Comparable key, boolean selected, boolean notify) { SelectableValue item = (SelectableValue) this.data.getObject(key); item.setSelected(selected); if (notify) { fireSelectionEvent(); } } public void clearSelection() { int itemCount = getItemCount(); for (int i = 0; i < itemCount; i++) { SelectableValue item = (SelectableValue) this.data.getObject(i); item.setSelected(false); } fireSelectionEvent(); } public void fireSelectionEvent() { this.fireDatasetChanged(new DatasetChangeInfo()); } }