jfreechart example source code file (CategoryPointerAnnotation.java)

This example jfreechart source code file (CategoryPointerAnnotation.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - jfreechart tags/keywords

awt, categorypointerannotation, categorypointerannotation, default_arrow_length, default_base_radius, default_label_offset, generalpath, generalpath, geometry, illegalargumentexception, io, ioexception, ioexception, null, paint, rectangleedge, stroke

The jfreechart CategoryPointerAnnotation.java source code

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2008, 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.]
 *
 * ------------------------------
 * CategoryPointerAnnotation.java
 * ------------------------------
 * (C) Copyright 2006-2008, by Object Refinery Limited.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   -;
 *
 * Changes:
 * --------
 * 02-Oct-2006 : Version 1 (DG);
 * 06-Mar-2007 : Implemented hashCode() (DG);
 *
 */

package org.jfree.chart.annotations;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Stroke;
import java.awt.geom.GeneralPath;
import java.awt.geom.Line2D;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

import org.jfree.chart.HashUtilities;
import org.jfree.chart.axis.CategoryAxis;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.Plot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.data.category.CategoryDataset;
import org.jfree.io.SerialUtilities;
import org.jfree.text.TextUtilities;
import org.jfree.ui.RectangleEdge;
import org.jfree.util.ObjectUtilities;
import org.jfree.util.PublicCloneable;

/**
 * An arrow and label that can be placed on a {@link CategoryPlot}.  The arrow
 * is drawn at a user-definable angle so that it points towards the (category,
 * value) location for the annotation.
 * <p>
 * The arrow length (and its offset from the (category, value) location) is
 * controlled by the tip radius and the base radius attributes.  Imagine two
 * circles around the (category, value) coordinate: the inner circle defined by
 * the tip radius, and the outer circle defined by the base radius.  Now, draw
 * the arrow starting at some point on the outer circle (the point is
 * determined by the angle), with the arrow tip being drawn at a corresponding
 * point on the inner circle.
 *
 * @since 1.0.3
 */
public class CategoryPointerAnnotation extends CategoryTextAnnotation
                                 implements Cloneable, PublicCloneable,
                                            Serializable {

    /** For serialization. */
    private static final long serialVersionUID = -4031161445009858551L;

    /** The default tip radius (in Java2D units). */
    public static final double DEFAULT_TIP_RADIUS = 10.0;

    /** The default base radius (in Java2D units). */
    public static final double DEFAULT_BASE_RADIUS = 30.0;

    /** The default label offset (in Java2D units). */
    public static final double DEFAULT_LABEL_OFFSET = 3.0;

    /** The default arrow length (in Java2D units). */
    public static final double DEFAULT_ARROW_LENGTH = 5.0;

    /** The default arrow width (in Java2D units). */
    public static final double DEFAULT_ARROW_WIDTH = 3.0;

    /** The angle of the arrow's line (in radians). */
    private double angle;

    /**
     * The radius from the (x, y) point to the tip of the arrow (in Java2D
     * units).
     */
    private double tipRadius;

    /**
     * The radius from the (x, y) point to the start of the arrow line (in
     * Java2D units).
     */
    private double baseRadius;

    /** The length of the arrow head (in Java2D units). */
    private double arrowLength;

    /** The arrow width (in Java2D units, per side). */
    private double arrowWidth;

    /** The arrow stroke. */
    private transient Stroke arrowStroke;

    /** The arrow paint. */
    private transient Paint arrowPaint;

    /** The radius from the base point to the anchor point for the label. */
    private double labelOffset;

    /**
     * Creates a new label and arrow annotation.
     *
     * @param label  the label (<code>null permitted).
     * @param key  the category key.
     * @param value  the y-value (measured against the chart's range axis).
     * @param angle  the angle of the arrow's line (in radians).
     */
    public CategoryPointerAnnotation(String label, Comparable key, double value,
            double angle) {

        super(label, key, value);
        this.angle = angle;
        this.tipRadius = DEFAULT_TIP_RADIUS;
        this.baseRadius = DEFAULT_BASE_RADIUS;
        this.arrowLength = DEFAULT_ARROW_LENGTH;
        this.arrowWidth = DEFAULT_ARROW_WIDTH;
        this.labelOffset = DEFAULT_LABEL_OFFSET;
        this.arrowStroke = new BasicStroke(1.0f);
        this.arrowPaint = Color.black;

    }

    /**
     * Returns the angle of the arrow.
     *
     * @return The angle (in radians).
     *
     * @see #setAngle(double)
     */
    public double getAngle() {
        return this.angle;
    }

    /**
     * Sets the angle of the arrow.
     *
     * @param angle  the angle (in radians).
     *
     * @see #getAngle()
     */
    public void setAngle(double angle) {
        this.angle = angle;
    }

    /**
     * Returns the tip radius.
     *
     * @return The tip radius (in Java2D units).
     *
     * @see #setTipRadius(double)
     */
    public double getTipRadius() {
        return this.tipRadius;
    }

    /**
     * Sets the tip radius.
     *
     * @param radius  the radius (in Java2D units).
     *
     * @see #getTipRadius()
     */
    public void setTipRadius(double radius) {
        this.tipRadius = radius;
    }

    /**
     * Returns the base radius.
     *
     * @return The base radius (in Java2D units).
     *
     * @see #setBaseRadius(double)
     */
    public double getBaseRadius() {
        return this.baseRadius;
    }

    /**
     * Sets the base radius.
     *
     * @param radius  the radius (in Java2D units).
     *
     * @see #getBaseRadius()
     */
    public void setBaseRadius(double radius) {
        this.baseRadius = radius;
    }

    /**
     * Returns the label offset.
     *
     * @return The label offset (in Java2D units).
     *
     * @see #setLabelOffset(double)
     */
    public double getLabelOffset() {
        return this.labelOffset;
    }

    /**
     * Sets the label offset (from the arrow base, continuing in a straight
     * line, in Java2D units).
     *
     * @param offset  the offset (in Java2D units).
     *
     * @see #getLabelOffset()
     */
    public void setLabelOffset(double offset) {
        this.labelOffset = offset;
    }

    /**
     * Returns the arrow length.
     *
     * @return The arrow length.
     *
     * @see #setArrowLength(double)
     */
    public double getArrowLength() {
        return this.arrowLength;
    }

    /**
     * Sets the arrow length.
     *
     * @param length  the length.
     *
     * @see #getArrowLength()
     */
    public void setArrowLength(double length) {
        this.arrowLength = length;
    }

    /**
     * Returns the arrow width.
     *
     * @return The arrow width (in Java2D units).
     *
     * @see #setArrowWidth(double)
     */
    public double getArrowWidth() {
        return this.arrowWidth;
    }

    /**
     * Sets the arrow width.
     *
     * @param width  the width (in Java2D units).
     *
     * @see #getArrowWidth()
     */
    public void setArrowWidth(double width) {
        this.arrowWidth = width;
    }

    /**
     * Returns the stroke used to draw the arrow line.
     *
     * @return The arrow stroke (never <code>null).
     *
     * @see #setArrowStroke(Stroke)
     */
    public Stroke getArrowStroke() {
        return this.arrowStroke;
    }

    /**
     * Sets the stroke used to draw the arrow line.
     *
     * @param stroke  the stroke (<code>null not permitted).
     *
     * @see #getArrowStroke()
     */
    public void setArrowStroke(Stroke stroke) {
        if (stroke == null) {
            throw new IllegalArgumentException("Null 'stroke' not permitted.");
        }
        this.arrowStroke = stroke;
    }

    /**
     * Returns the paint used for the arrow.
     *
     * @return The arrow paint (never <code>null).
     *
     * @see #setArrowPaint(Paint)
     */
    public Paint getArrowPaint() {
        return this.arrowPaint;
    }

    /**
     * Sets the paint used for the arrow.
     *
     * @param paint  the arrow paint (<code>null not permitted).
     *
     * @see #getArrowPaint()
     */
    public void setArrowPaint(Paint paint) {
        if (paint == null) {
            throw new IllegalArgumentException("Null 'paint' argument.");
        }
        this.arrowPaint = paint;
    }

    /**
     * Draws the annotation.
     *
     * @param g2  the graphics device.
     * @param plot  the plot.
     * @param dataArea  the data area.
     * @param domainAxis  the domain axis.
     * @param rangeAxis  the range axis.
     */
    public void draw(Graphics2D g2, CategoryPlot plot, Rectangle2D dataArea,
            CategoryAxis domainAxis, ValueAxis rangeAxis) {

        PlotOrientation orientation = plot.getOrientation();
        RectangleEdge domainEdge = Plot.resolveDomainAxisLocation(
                plot.getDomainAxisLocation(), orientation);
        RectangleEdge rangeEdge = Plot.resolveRangeAxisLocation(
                plot.getRangeAxisLocation(), orientation);
        CategoryDataset dataset = plot.getDataset();
        int catIndex = dataset.getColumnIndex(getCategory());
        int catCount = dataset.getColumnCount();
        double j2DX = domainAxis.getCategoryMiddle(catIndex, catCount,
                dataArea, domainEdge);
        double j2DY = rangeAxis.valueToJava2D(getValue(), dataArea, rangeEdge);
        if (orientation == PlotOrientation.HORIZONTAL) {
            double temp = j2DX;
            j2DX = j2DY;
            j2DY = temp;
        }
        double startX = j2DX + Math.cos(this.angle) * this.baseRadius;
        double startY = j2DY + Math.sin(this.angle) * this.baseRadius;

        double endX = j2DX + Math.cos(this.angle) * this.tipRadius;
        double endY = j2DY + Math.sin(this.angle) * this.tipRadius;

        double arrowBaseX = endX + Math.cos(this.angle) * this.arrowLength;
        double arrowBaseY = endY + Math.sin(this.angle) * this.arrowLength;

        double arrowLeftX = arrowBaseX
            + Math.cos(this.angle + Math.PI / 2.0) * this.arrowWidth;
        double arrowLeftY = arrowBaseY
            + Math.sin(this.angle + Math.PI / 2.0) * this.arrowWidth;

        double arrowRightX = arrowBaseX
            - Math.cos(this.angle + Math.PI / 2.0) * this.arrowWidth;
        double arrowRightY = arrowBaseY
            - Math.sin(this.angle + Math.PI / 2.0) * this.arrowWidth;

        GeneralPath arrow = new GeneralPath();
        arrow.moveTo((float) endX, (float) endY);
        arrow.lineTo((float) arrowLeftX, (float) arrowLeftY);
        arrow.lineTo((float) arrowRightX, (float) arrowRightY);
        arrow.closePath();

        g2.setStroke(this.arrowStroke);
        g2.setPaint(this.arrowPaint);
        Line2D line = new Line2D.Double(startX, startY, endX, endY);
        g2.draw(line);
        g2.fill(arrow);

        // draw the label
        g2.setFont(getFont());
        g2.setPaint(getPaint());
        double labelX = j2DX
            + Math.cos(this.angle) * (this.baseRadius + this.labelOffset);
        double labelY = j2DY
            + Math.sin(this.angle) * (this.baseRadius + this.labelOffset);
        /* Rectangle2D hotspot = */ TextUtilities.drawAlignedString(getText(),
                g2, (float) labelX, (float) labelY, getTextAnchor());
        // TODO: implement the entity for the annotation

    }

    /**
     * Tests this annotation for equality with an arbitrary object.
     *
     * @param obj  the object (<code>null permitted).
     *
     * @return <code>true or false.
     */
    public boolean equals(Object obj) {

        if (obj == this) {
            return true;
        }
        if (!(obj instanceof CategoryPointerAnnotation)) {
            return false;
        }
        if (!super.equals(obj)) {
            return false;
        }
        CategoryPointerAnnotation that = (CategoryPointerAnnotation) obj;
        if (this.angle != that.angle) {
            return false;
        }
        if (this.tipRadius != that.tipRadius) {
            return false;
        }
        if (this.baseRadius != that.baseRadius) {
            return false;
        }
        if (this.arrowLength != that.arrowLength) {
            return false;
        }
        if (this.arrowWidth != that.arrowWidth) {
            return false;
        }
        if (!this.arrowPaint.equals(that.arrowPaint)) {
            return false;
        }
        if (!ObjectUtilities.equal(this.arrowStroke, that.arrowStroke)) {
            return false;
        }
        if (this.labelOffset != that.labelOffset) {
            return false;
        }
        return true;
    }

    /**
     * Returns a hash code for this instance.
     *
     * @return A hash code.
     */
    public int hashCode() {
        int result = 193;
        long temp = Double.doubleToLongBits(this.angle);
        result = 37 * result + (int) (temp ^ (temp >>> 32));
        temp = Double.doubleToLongBits(this.tipRadius);
        result = 37 * result + (int) (temp ^ (temp >>> 32));
        temp = Double.doubleToLongBits(this.baseRadius);
        result = 37 * result + (int) (temp ^ (temp >>> 32));
        temp = Double.doubleToLongBits(this.arrowLength);
        result = 37 * result + (int) (temp ^ (temp >>> 32));
        temp = Double.doubleToLongBits(this.arrowWidth);
        result = 37 * result + (int) (temp ^ (temp >>> 32));
        result = 37 * result + HashUtilities.hashCodeForPaint(this.arrowPaint);
        result = 37 * result + this.arrowStroke.hashCode();
        temp = Double.doubleToLongBits(this.labelOffset);
        result = 37 * result + (int) (temp ^ (temp >>> 32));
        return result;
    }

    /**
     * Returns a clone of the annotation.
     *
     * @return A clone.
     *
     * @throws CloneNotSupportedException  if the annotation can't be cloned.
     */
    public Object clone() throws CloneNotSupportedException {
        return super.clone();
    }

    /**
     * Provides serialization support.
     *
     * @param stream  the output stream.
     *
     * @throws IOException if there is an I/O error.
     */
    private void writeObject(ObjectOutputStream stream) throws IOException {
        stream.defaultWriteObject();
        SerialUtilities.writePaint(this.arrowPaint, stream);
        SerialUtilities.writeStroke(this.arrowStroke, stream);
    }

    /**
     * Provides serialization support.
     *
     * @param stream  the input stream.
     *
     * @throws IOException  if there is an I/O error.
     * @throws ClassNotFoundException  if there is a classpath problem.
     */
    private void readObject(ObjectInputStream stream)
        throws IOException, ClassNotFoundException {
        stream.defaultReadObject();
        this.arrowPaint = SerialUtilities.readPaint(stream);
        this.arrowStroke = SerialUtilities.readStroke(stream);
    }

}