barrenderer.java

来自「JfreeChart 常用图表例子」· Java 代码 · 共 1,014 行 · 第 1/3 页

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2005, 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.]
 *
 * ----------------
 * BarRenderer.java
 * ----------------
 * (C) Copyright 2002-2005, by Object Refinery Limited.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   Christian W. Zuckschwerdt;
 *
 * $Id: BarRenderer.java,v 1.13 2005/06/02 08:38:36 mungady Exp $
 *
 * Changes
 * -------
 * 14-Mar-2002 : Version 1 (DG);
 * 23-May-2002 : Added tooltip generator to renderer (DG);
 * 29-May-2002 : Moved tooltip generator to abstract super-class (DG);
 * 25-Jun-2002 : Changed constructor to protected and removed redundant 
 *               code (DG);
 * 26-Jun-2002 : Added axis to initialise method, and record upper and lower 
 *               clip values (DG);
 * 24-Sep-2002 : Added getLegendItem() method (DG);
 * 09-Oct-2002 : Modified constructor to include URL generator (DG);
 * 05-Nov-2002 : Base dataset is now TableDataset not CategoryDataset (DG);
 * 10-Jan-2003 : Moved get/setItemMargin() method up from subclasses (DG);
 * 17-Jan-2003 : Moved plot classes into a separate package (DG);
 * 25-Mar-2003 : Implemented Serializable (DG);
 * 01-May-2003 : Modified clipping to allow for dual axes and datasets (DG);
 * 12-May-2003 : Merged horizontal and vertical bar renderers (DG);
 * 12-Jun-2003 : Updates for item labels (DG);
 * 30-Jul-2003 : Modified entity constructor (CZ);
 * 02-Sep-2003 : Changed initialise method to fix bug 790407 (DG);
 * 16-Sep-2003 : Changed ChartRenderingInfo --> PlotRenderingInfo (DG);
 * 07-Oct-2003 : Added renderer state (DG);
 * 27-Oct-2003 : Merged drawHorizontalItem() and drawVerticalItem() 
 *               methods (DG);
 * 28-Oct-2003 : Added support for gradient paint on bars (DG);
 * 14-Nov-2003 : Added 'maxBarWidth' attribute (DG);
 * 10-Feb-2004 : Small changes inside drawItem() method to ease cut-and-paste 
 *               overriding (DG);
 * 19-Mar-2004 : Fixed bug introduced with separation of tool tip and item 
 *               label generators.  Fixed equals() method (DG);
 * 11-May-2004 : Fix for null pointer exception (bug id 951127) (DG);
 * 05-Nov-2004 : Modified drawItem() signature (DG);
 * 26-Jan-2005 : Provided override for getLegendItem() method (DG);
 * 20-Apr-2005 : Generate legend labels, tooltips and URLs (DG);
 * 18-May-2005 : Added configurable base value (DG);
 * 
 */

package org.jfree.chart.renderer.category;

import java.awt.Font;
import java.awt.GradientPaint;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.io.Serializable;

import org.jfree.chart.LegendItem;
import org.jfree.chart.axis.CategoryAxis;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.entity.CategoryItemEntity;
import org.jfree.chart.entity.EntityCollection;
import org.jfree.chart.event.RendererChangeEvent;
import org.jfree.chart.labels.CategoryItemLabelGenerator;
import org.jfree.chart.labels.CategoryToolTipGenerator;
import org.jfree.chart.labels.ItemLabelAnchor;
import org.jfree.chart.labels.ItemLabelPosition;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.PlotRenderingInfo;
import org.jfree.data.category.CategoryDataset;
import org.jfree.text.TextUtilities;
import org.jfree.ui.GradientPaintTransformer;
import org.jfree.ui.RectangleEdge;
import org.jfree.ui.StandardGradientPaintTransformer;
import org.jfree.util.ObjectUtilities;
import org.jfree.util.PublicCloneable;

/**
 * A {@link CategoryItemRenderer} that draws individual data items as bars.
 */
public class BarRenderer extends AbstractCategoryItemRenderer 
                         implements Cloneable, PublicCloneable, Serializable {

    /** For serialization. */
    private static final long serialVersionUID = 6000649414965887481L;
    
    /** The default item margin percentage. */
    public static final double DEFAULT_ITEM_MARGIN = 0.20;

    /** 
     * Constant that controls the minimum width before a bar has an outline 
     * drawn. 
     */
    public static final double BAR_OUTLINE_WIDTH_THRESHOLD = 3.0;

    /** The margin between items (bars) within a category. */
    private double itemMargin;

    /** A flag that controls whether or not bar outlines are drawn. */
    private boolean drawBarOutline;
    
    /** The maximum bar width as a percentage of the available space. */
    private double maxBarWidth;
    
    /** The minimum bar length (in Java2D units). */
    private double minimumBarLength;
    
    /** 
     * An optional class used to transform gradient paint objects to fit each 
     * bar. 
     */
    private GradientPaintTransformer gradientPaintTransformer;
    
    /** 
     * The fallback position if a positive item label doesn't fit inside the 
     * bar. 
     */
    private ItemLabelPosition positiveItemLabelPositionFallback;
    
    /** 
     * The fallback position if a negative item label doesn't fit inside the 
     * bar. 
     */
    private ItemLabelPosition negativeItemLabelPositionFallback;
    
    /** The upper clip (axis) value for the axis. */
    private double upperClip;  
    // TODO:  this needs to move into the renderer state

    /** The lower clip (axis) value for the axis. */
    private double lowerClip;  
    // TODO:  this needs to move into the renderer state

    private double base;
    
    /**
     * Creates a new bar renderer with default settings.
     */
    public BarRenderer() {
        super();
        this.base = 0;
        this.itemMargin = DEFAULT_ITEM_MARGIN;
        this.drawBarOutline = true;
        this.maxBarWidth = 1.0;  
            // 100 percent, so it will not apply unless changed
        this.positiveItemLabelPositionFallback = null;
        this.negativeItemLabelPositionFallback = null;
        this.gradientPaintTransformer = new StandardGradientPaintTransformer();
        this.minimumBarLength = 0.0;
    }

    /**
     * Returns the base value for the bars.
     * 
     * @return The base value for the bars.
     */
    public double getBase() {
        return this.base;    
    }
    
    /**
     * Sets the base value for the bars and sends a {@link RendererChangeEvent}
     * to all registered listeners.
     * 
     * @param base  the new base value.
     */
    public void setBase(double base) {
        this.base = base;
        notifyListeners(new RendererChangeEvent(this));
    }
    
    /**
     * Returns the item margin as a percentage of the available space for all 
     * bars.
     *
     * @return The margin percentage (where 0.10 is ten percent).
     */
    public double getItemMargin() {
        return this.itemMargin;
    }

    /**
     * Sets the item margin and sends a {@link RendererChangeEvent} to all 
     * registered listeners.  The value is expressed as a percentage of the 
     * available width for plotting all the bars, with the resulting amount to 
     * be distributed between all the bars evenly.
     *
     * @param percent  the margin (where 0.10 is ten percent).
     */
    public void setItemMargin(double percent) {
        this.itemMargin = percent;
        notifyListeners(new RendererChangeEvent(this));
    }

    /**
     * Returns a flag that controls whether or not bar outlines are drawn.
     * 
     * @return A boolean.
     */
    public boolean isDrawBarOutline() {
        return this.drawBarOutline;    
    }
    
    /**
     * Sets the flag that controls whether or not bar outlines are drawn and 
     * sends a {@link RendererChangeEvent} to all registered listeners.
     * 
     * @param draw  the flag.
     */
    public void setDrawBarOutline(boolean draw) {
        this.drawBarOutline = draw;
        notifyListeners(new RendererChangeEvent(this));
    }
    
    /**
     * Returns the maximum bar width, as a percentage of the available drawing 
     * space.
     * 
     * @return The maximum bar width.
     */
    public double getMaxBarWidth() {
        return this.maxBarWidth;
    }
    
    /**
     * Sets the maximum bar width, which is specified as a percentage of the 
     * available space for all bars, and sends a {@link RendererChangeEvent} to
     * all registered listeners.
     * 
     * @param percent  the percent (where 0.05 is five percent).
     */
    public void setMaxBarWidth(double percent) {
        this.maxBarWidth = percent;
        notifyListeners(new RendererChangeEvent(this));
    }

    /**
     * Returns the minimum bar length (in Java2D units).
     * 
     * @return The minimum bar length.
     */
    public double getMinimumBarLength() {
        return this.minimumBarLength;
    }
    
    /**
     * Sets the minimum bar length and sends a {@link RendererChangeEvent} to 
     * all registered listeners.  The minimum bar length is specified in Java2D
     * units, and can be used to prevent bars that represent very small data 
     * values from disappearing when drawn on the screen.
     * 
     * @param min  the minimum bar length (in Java2D units).
     */
    public void setMinimumBarLength(double min) {
        this.minimumBarLength = min;
        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));
    }
    
    /**
     * Returns the fallback position for positive item labels that don't fit 
     * within a bar.
     * 
     * @return The fallback position (<code>null</code> possible).
     */
    public ItemLabelPosition getPositiveItemLabelPositionFallback() {
        return this.positiveItemLabelPositionFallback;
    }
    
    /**
     * Sets the fallback position for positive item labels that don't fit 
     * within a bar, and sends a {@link RendererChangeEvent} to all registered
     * listeners.
     * 
     * @param position  the position (<code>null</code> permitted).
     */
    public void setPositiveItemLabelPositionFallback(
            ItemLabelPosition position) {
        this.positiveItemLabelPositionFallback = position;
        notifyListeners(new RendererChangeEvent(this));
    }
    
    /**
     * Returns the fallback position for negative item labels that don't fit 
     * within a bar.
     * 
     * @return The fallback position (<code>null</code> possible).
     */