Java tutorial
/* * =========================================================== * JFreeChart : a free chart library for the Java(tm) platform * =========================================================== * (C) Copyright 2000-2004, 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., 59 Temple Place, Suite 330, * Boston, MA 02111-1307, USA. * [Java is a trademark or registered trademark of Sun Microsystems, Inc. * in the United States and other countries.] * ------------------ * XYBarRenderer.java * ------------------ * (C) Copyright 2001-2004, by Object Refinery Limited. * Original Author: David Gilbert (for Object Refinery Limited); * Contributor(s): Richard Atkinson; * Christian W. Zuckschwerdt; * Bill Kelemen; * $Id: XYBarRenderer.java,v 1.1 2011-01-31 09:02:48 klukas Exp $ * Changes * ------- * 13-Dec-2001 : Version 1, makes VerticalXYBarPlot class redundant (DG); * 23-Jan-2002 : Added DrawInfo parameter to drawItem(...) method (DG); * 09-Apr-2002 : Removed the translated zero from the drawItem method. Override the initialise() * method to calculate it (DG); * 24-May-2002 : Incorporated tooltips into chart entities (DG); * 25-Jun-2002 : Removed redundant import (DG); * 05-Aug-2002 : Small modification to drawItem method to support URLs for HTML image maps (RA); * 25-Mar-2003 : Implemented Serializable (DG); * 01-May-2003 : Modified drawItem(...) method signature (DG); * 30-Jul-2003 : Modified entity constructor (CZ); * 20-Aug-2003 : Implemented Cloneable and PublicCloneable (DG); * 24-Aug-2003 : Added null checks in drawItem (BK); * 16-Sep-2003 : Changed ChartRenderingInfo --> PlotRenderingInfo (DG); * 07-Oct-2003 : Added renderer state (DG); * 05-Dec-2003 : Changed call to obtain outline paint (DG); * 10-Feb-2004 : Added state class, updated drawItem() method to make cut-and-paste overriding * easier, and replaced property change with RendererChangeEvent (DG); * 25-Feb-2004 : Replaced CrosshairInfo with CrosshairState (DG); * 26-Apr-2004 : Added gradient paint transformer (DG); * 19-May-2004 : Fixed bug (879709) with bar zero value for secondary axis (DG); */ package org.jfree.chart.renderer; import java.awt.GradientPaint; import java.awt.Graphics2D; import java.awt.Paint; import java.awt.geom.Rectangle2D; import java.io.Serializable; import org.jfree.chart.axis.ValueAxis; import org.jfree.chart.entity.EntityCollection; import org.jfree.chart.entity.XYItemEntity; import org.jfree.chart.event.RendererChangeEvent; import org.jfree.chart.labels.XYToolTipGenerator; import org.jfree.chart.plot.CrosshairState; import org.jfree.chart.plot.PlotOrientation; import org.jfree.chart.plot.PlotRenderingInfo; import org.jfree.chart.plot.XYPlot; import org.jfree.data.IntervalXYDataset; import org.jfree.data.XYDataset; import org.jfree.ui.GradientPaintTransformer; import org.jfree.ui.RectangleEdge; import org.jfree.ui.StandardGradientPaintTransformer; import org.jfree.util.PublicCloneable; /** * A renderer that draws bars on an {@link XYPlot} (requires an {@link IntervalXYDataset}). * <P> * This renderer does not include any code for calculating the crosshair point. */ public class XYBarRenderer extends AbstractXYItemRenderer implements XYItemRenderer, Cloneable, PublicCloneable, Serializable { /** * The state class used by this renderer. */ class XYBarRendererState extends XYItemRendererState { /** Zero on the range axis in Java 2D space. */ private double g2Zero; /** * Creates a new state object. * * @param info * the plot rendering info. */ public XYBarRendererState(PlotRenderingInfo info) { super(info); } /** * Returns the range axis zero in Java 2D space. * * @return The range axis zero. */ public double getG2Zero() { return this.g2Zero; } /** * Sets the range axis zero in Java2D space. * * @param value * the value. */ public void setG2Zero(double value) { this.g2Zero = value; } } /** Percentage margin (to reduce the width of bars). */ private double margin; /** An optional class used to transform gradient paint objects to fit each bar. */ private GradientPaintTransformer gradientPaintTransformer; /** * The default constructor. */ public XYBarRenderer() { this(0.0); } /** * Constructs a new renderer. * * @param margin * the percentage amount to trim from the width of each bar. */ public XYBarRenderer(double margin) { super(); this.margin = margin; this.gradientPaintTransformer = new StandardGradientPaintTransformer(); } /** * Returns the margin which is a percentage amount by which the bars are trimmed. * * @return The margin. */ public double getMargin() { return this.margin; } /** * Sets the percentage amount by which the bars are trimmed and sends a {@link RendererChangeEvent} to all registered listeners. * * @param margin * the new margin. */ public void setMargin(double margin) { this.margin = margin; notifyListeners(new RendererChangeEvent(this)); } /** * Returns the gradient paint transformer (an object used to transform gradient paint objects * to fit each bar. * * @return A transformer (<code>null</code> possible). */ public GradientPaintTransformer getGradientPaintTransformer() { return this.gradientPaintTransformer; } /** * Sets the gradient paint transformer and sends a {@link RendererChangeEvent} to all registered * listeners. * * @param transformer * the transformer (<code>null</code> permitted). */ public void setGradientPaintTransformer(GradientPaintTransformer transformer) { this.gradientPaintTransformer = transformer; notifyListeners(new RendererChangeEvent(this)); } /** * Initialises the renderer and returns a state object that should be passed to all subsequent * calls to the drawItem() method. Here we calculate the Java2D y-coordinate for zero, since * all the bars have their bases fixed at zero. * * @param g2 * the graphics device. * @param dataArea * the area inside the axes. * @param plot * the plot. * @param dataset * the data. * @param info * an optional info collection object to return data back to the caller. * @return A state object. */ public XYItemRendererState initialise(Graphics2D g2, Rectangle2D dataArea, XYPlot plot, XYDataset dataset, PlotRenderingInfo info) { XYBarRendererState state = new XYBarRendererState(info); ValueAxis rangeAxis = plot.getRangeAxisForDataset(plot.indexOf(dataset)); state.setG2Zero(rangeAxis.valueToJava2D(0.0, dataArea, plot.getRangeAxisEdge())); return state; } /** * Draws the visual representation of a single data item. * * @param g2 * the graphics device. * @param state * the renderer state. * @param dataArea * the area within which the plot is being drawn. * @param info * collects information about the drawing. * @param plot * the plot (can be used to obtain standard color information etc). * @param domainAxis * the domain axis. * @param rangeAxis * the range axis. * @param dataset * the dataset. * @param series * the series index (zero-based). * @param item * the item index (zero-based). * @param crosshairState * crosshair information for the plot (<code>null</code> permitted). * @param pass * the pass index. */ public void drawItem(Graphics2D g2, XYItemRendererState state, Rectangle2D dataArea, PlotRenderingInfo info, XYPlot plot, ValueAxis domainAxis, ValueAxis rangeAxis, XYDataset dataset, int series, int item, CrosshairState crosshairState, int pass) { IntervalXYDataset intervalDataset = (IntervalXYDataset) dataset; Paint seriesOutlinePaint = getItemOutlinePaint(series, item); Number valueNumber = intervalDataset.getYValue(series, item); if (valueNumber == null) { return; } double translatedValue = rangeAxis.valueToJava2D(valueNumber.doubleValue(), dataArea, plot.getRangeAxisEdge()); RectangleEdge location = plot.getDomainAxisEdge(); Number startXNumber = intervalDataset.getStartXValue(series, item); if (startXNumber == null) { return; } double translatedStartX = domainAxis.valueToJava2D(startXNumber.doubleValue(), dataArea, location); Number endXNumber = intervalDataset.getEndXValue(series, item); if (endXNumber == null) { return; } double translatedEndX = domainAxis.valueToJava2D(endXNumber.doubleValue(), dataArea, location); XYBarRendererState s = (XYBarRendererState) state; double g2Zero = s.getG2Zero(); double translatedWidth = Math.max(1, Math.abs(translatedEndX - translatedStartX)); double translatedHeight = Math.abs(translatedValue - g2Zero); if (getMargin() > 0.0) { double cut = translatedWidth * getMargin(); translatedWidth = translatedWidth - cut; translatedStartX = translatedStartX + cut / 2; } Rectangle2D bar = null; PlotOrientation orientation = plot.getOrientation(); if (orientation == PlotOrientation.HORIZONTAL) { bar = new Rectangle2D.Double(Math.min(g2Zero, translatedValue), translatedEndX, translatedHeight, translatedWidth); } else if (orientation == PlotOrientation.VERTICAL) { bar = new Rectangle2D.Double(translatedStartX, Math.min(g2Zero, translatedValue), translatedWidth, translatedHeight); } Paint itemPaint = getItemPaint(series, item); if (getGradientPaintTransformer() != null && itemPaint instanceof GradientPaint) { GradientPaint gp = (GradientPaint) itemPaint; itemPaint = getGradientPaintTransformer().transform(gp, bar); } g2.setPaint(itemPaint); g2.fill(bar); if (Math.abs(translatedEndX - translatedStartX) > 3) { g2.setStroke(getItemStroke(series, item)); g2.setPaint(seriesOutlinePaint); g2.draw(bar); } // add an entity for the item... if (info != null) { EntityCollection entities = info.getOwner().getEntityCollection(); if (entities != null) { String tip = null; XYToolTipGenerator generator = getToolTipGenerator(series, item); if (generator != null) { tip = generator.generateToolTip(dataset, series, item); } String url = null; if (getURLGenerator() != null) { url = getURLGenerator().generateURL(dataset, series, item); } XYItemEntity entity = new XYItemEntity(bar, dataset, series, item, tip, url); entities.addEntity(entity); } } } /** * Returns a clone of the renderer. * * @return A clone. * @throws CloneNotSupportedException * if the renderer cannot be cloned. */ public Object clone() throws CloneNotSupportedException { return super.clone(); } }