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.] * * --------------------------- * SimpleHistogramDataset.java * --------------------------- * (C) Copyright 2005-2013, by Object Refinery Limited and Contributors. * * Original Author: David Gilbert (for Object Refinery Limited); * Contributor(s): Sergei Ivanov; * * Changes * ------- * 10-Jan-2005 : Version 1 (DG); * 21-May-2007 : Added clearObservations() and removeAllBins() (SI); * 10-Jul-2007 : Added null argument check to constructor (DG); * 03-Jul-2013 : Use ParamChecks (DG); * */ package org.jfree.data.statistics; import java.io.Serializable; import java.util.ArrayList; import java.util.Collections; import java.util.Iterator; import java.util.List; import org.jfree.chart.util.ParamChecks; import org.jfree.data.DomainOrder; import org.jfree.data.general.DatasetChangeEvent; import org.jfree.data.xy.AbstractIntervalXYDataset; import org.jfree.data.xy.IntervalXYDataset; import org.jfree.util.ObjectUtilities; import org.jfree.util.PublicCloneable; /** * A dataset used for creating simple histograms with custom defined bins. * * @see HistogramDataset */ public class SimpleHistogramDataset extends AbstractIntervalXYDataset implements IntervalXYDataset, Cloneable, PublicCloneable, Serializable { /** For serialization. */ private static final long serialVersionUID = 7997996479768018443L; /** The series key. */ private Comparable key; /** The bins. */ private List bins; /** * A flag that controls whether or not the bin count is divided by the * bin size. */ private boolean adjustForBinSize; /** * Creates a new histogram dataset. Note that the * <code>adjustForBinSize</code> flag defaults to <code>true</code>. * * @param key the series key (<code>null</code> not permitted). */ public SimpleHistogramDataset(Comparable key) { ParamChecks.nullNotPermitted(key, "key"); this.key = key; this.bins = new ArrayList(); this.adjustForBinSize = true; } /** * Returns a flag that controls whether or not the bin count is divided by * the bin size in the {@link #getXValue(int, int)} method. * * @return A boolean. * * @see #setAdjustForBinSize(boolean) */ public boolean getAdjustForBinSize() { return this.adjustForBinSize; } /** * Sets the flag that controls whether or not the bin count is divided by * the bin size in the {@link #getYValue(int, int)} method, and sends a * {@link DatasetChangeEvent} to all registered listeners. * * @param adjust the flag. * * @see #getAdjustForBinSize() */ public void setAdjustForBinSize(boolean adjust) { this.adjustForBinSize = adjust; notifyListeners(new DatasetChangeEvent(this, this)); } /** * Returns the number of series in the dataset (always 1 for this dataset). * * @return The series count. */ @Override public int getSeriesCount() { return 1; } /** * Returns the key for a series. Since this dataset only stores a single * series, the <code>series</code> argument is ignored. * * @param series the series (zero-based index, ignored in this dataset). * * @return The key for the series. */ @Override public Comparable getSeriesKey(int series) { return this.key; } /** * Returns the order of the domain (or X) values returned by the dataset. * * @return The order (never <code>null</code>). */ @Override public DomainOrder getDomainOrder() { return DomainOrder.ASCENDING; } /** * Returns the number of items in a series. Since this dataset only stores * a single series, the <code>series</code> argument is ignored. * * @param series the series index (zero-based, ignored in this dataset). * * @return The item count. */ @Override public int getItemCount(int series) { return this.bins.size(); } /** * Adds a bin to the dataset. An exception is thrown if the bin overlaps * with any existing bin in the dataset. * * @param bin the bin (<code>null</code> not permitted). * * @see #removeAllBins() */ public void addBin(SimpleHistogramBin bin) { // check that the new bin doesn't overlap with any existing bin Iterator iterator = this.bins.iterator(); while (iterator.hasNext()) { SimpleHistogramBin existingBin = (SimpleHistogramBin) iterator.next(); if (bin.overlapsWith(existingBin)) { throw new RuntimeException("Overlapping bin"); } } this.bins.add(bin); Collections.sort(this.bins); } /** * Adds an observation to the dataset (by incrementing the item count for * the appropriate bin). A runtime exception is thrown if the value does * not fit into any bin. * * @param value the value. */ public void addObservation(double value) { addObservation(value, true); } /** * Adds an observation to the dataset (by incrementing the item count for * the appropriate bin). A runtime exception is thrown if the value does * not fit into any bin. * * @param value the value. * @param notify send {@link DatasetChangeEvent} to listeners? */ public void addObservation(double value, boolean notify) { boolean placed = false; Iterator iterator = this.bins.iterator(); while (iterator.hasNext() && !placed) { SimpleHistogramBin bin = (SimpleHistogramBin) iterator.next(); if (bin.accepts(value)) { bin.setItemCount(bin.getItemCount() + 1); placed = true; } } if (!placed) { throw new RuntimeException("No bin."); } if (notify) { notifyListeners(new DatasetChangeEvent(this, this)); } } /** * Adds a set of values to the dataset and sends a * {@link DatasetChangeEvent} to all registered listeners. * * @param values the values (<code>null</code> not permitted). * * @see #clearObservations() */ public void addObservations(double[] values) { for (int i = 0; i < values.length; i++) { addObservation(values[i], false); } notifyListeners(new DatasetChangeEvent(this, this)); } /** * Removes all current observation data and sends a * {@link DatasetChangeEvent} to all registered listeners. * * @since 1.0.6 * * @see #addObservations(double[]) * @see #removeAllBins() */ public void clearObservations() { Iterator iterator = this.bins.iterator(); while (iterator.hasNext()) { SimpleHistogramBin bin = (SimpleHistogramBin) iterator.next(); bin.setItemCount(0); } notifyListeners(new DatasetChangeEvent(this, this)); } /** * Removes all bins and sends a {@link DatasetChangeEvent} to all * registered listeners. * * @since 1.0.6 * * @see #addBin(SimpleHistogramBin) */ public void removeAllBins() { this.bins = new ArrayList(); notifyListeners(new DatasetChangeEvent(this, this)); } /** * Returns the x-value for an item within a series. The x-values may or * may not be returned in ascending order, that is up to the class * implementing the interface. * * @param series the series index (zero-based). * @param item the item index (zero-based). * * @return The x-value (never <code>null</code>). */ @Override public Number getX(int series, int item) { return new Double(getXValue(series, item)); } /** * Returns the x-value (as a double primitive) for an item within a series. * * @param series the series index (zero-based). * @param item the item index (zero-based). * * @return The x-value. */ @Override public double getXValue(int series, int item) { SimpleHistogramBin bin = (SimpleHistogramBin) this.bins.get(item); return (bin.getLowerBound() + bin.getUpperBound()) / 2.0; } /** * Returns the y-value for an item within a series. * * @param series the series index (zero-based). * @param item the item index (zero-based). * * @return The y-value (possibly <code>null</code>). */ @Override public Number getY(int series, int item) { return new Double(getYValue(series, item)); } /** * Returns the y-value (as a double primitive) for an item within a series. * * @param series the series index (zero-based). * @param item the item index (zero-based). * * @return The y-value. * * @see #getAdjustForBinSize() */ @Override public double getYValue(int series, int item) { SimpleHistogramBin bin = (SimpleHistogramBin) this.bins.get(item); if (this.adjustForBinSize) { return bin.getItemCount() / (bin.getUpperBound() - bin.getLowerBound()); } else { return bin.getItemCount(); } } /** * Returns the starting X value for the specified series and item. * * @param series the series index (zero-based). * @param item the item index (zero-based). * * @return The value. */ @Override public Number getStartX(int series, int item) { return new Double(getStartXValue(series, item)); } /** * Returns the start x-value (as a double primitive) for an item within a * series. * * @param series the series (zero-based index). * @param item the item (zero-based index). * * @return The start x-value. */ @Override public double getStartXValue(int series, int item) { SimpleHistogramBin bin = (SimpleHistogramBin) this.bins.get(item); return bin.getLowerBound(); } /** * Returns the ending X value for the specified series and item. * * @param series the series index (zero-based). * @param item the item index (zero-based). * * @return The value. */ @Override public Number getEndX(int series, int item) { return new Double(getEndXValue(series, item)); } /** * Returns the end x-value (as a double primitive) for an item within a * series. * * @param series the series index (zero-based). * @param item the item index (zero-based). * * @return The end x-value. */ @Override public double getEndXValue(int series, int item) { SimpleHistogramBin bin = (SimpleHistogramBin) this.bins.get(item); return bin.getUpperBound(); } /** * Returns the starting Y value for the specified series and item. * * @param series the series index (zero-based). * @param item the item index (zero-based). * * @return The value. */ @Override public Number getStartY(int series, int item) { return getY(series, item); } /** * Returns the start y-value (as a double primitive) for an item within a * series. * * @param series the series index (zero-based). * @param item the item index (zero-based). * * @return The start y-value. */ @Override public double getStartYValue(int series, int item) { return getYValue(series, item); } /** * Returns the ending Y value for the specified series and item. * * @param series the series index (zero-based). * @param item the item index (zero-based). * * @return The value. */ @Override public Number getEndY(int series, int item) { return getY(series, item); } /** * Returns the end y-value (as a double primitive) for an item within a * series. * * @param series the series index (zero-based). * @param item the item index (zero-based). * * @return The end y-value. */ @Override public double getEndYValue(int series, int item) { return getYValue(series, item); } /** * Compares the dataset for equality with an arbitrary object. * * @param obj the object (<code>null</code> permitted). * * @return A boolean. */ @Override public boolean equals(Object obj) { if (obj == this) { return true; } if (!(obj instanceof SimpleHistogramDataset)) { return false; } SimpleHistogramDataset that = (SimpleHistogramDataset) obj; if (!this.key.equals(that.key)) { return false; } if (this.adjustForBinSize != that.adjustForBinSize) { return false; } if (!this.bins.equals(that.bins)) { return false; } return true; } /** * Returns a clone of the dataset. * * @return A clone. * * @throws CloneNotSupportedException not thrown by this class, but maybe * by subclasses (if any). */ @Override public Object clone() throws CloneNotSupportedException { SimpleHistogramDataset clone = (SimpleHistogramDataset) super.clone(); clone.bins = (List) ObjectUtilities.deepClone(this.bins); return clone; } }