xytextannotation.java

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/* ======================================
 * JFreeChart : a free Java chart library
 * ======================================
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 * Project Lead:  David Gilbert ([e-mail]);
 *
 * (C) Copyright 2000-2003, by Object Refinery Limited and Contributors.
 *
 * 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.
 *
 * ---------------------
 * XYTextAnnotation.java
 * ---------------------
 * (C) Copyright 2002, 2003 by Object Refinery Limited.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   -;
 *
 * $Id: XYTextAnnotation.java,v 1.6 2003/07/21 10:13:23 mungady Exp $
 *
 * Changes:
 * --------
 * 28-Aug-2002 : Version 1 (DG);
 * 07-Nov-2002 : Fixed errors reported by Checkstyle (DG);
 * 13-Jan-2003 : Reviewed Javadocs (DG);
 * 26-Mar-2003 : Implemented Serializable (DG);
 * 02-Jul-2003 : Added new text alignment and rotation options (DG);
 *
 */

package org.jfree.chart.annotations;

import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import java.io.Serializable;

import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.plot.Plot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.ui.RectangleEdge;
import org.jfree.ui.RefineryUtilities;

/**
 * A text annotation that can be placed at a particular (x, y) location on an {@link XYPlot}.
 *
 * @author David Gilbert
 */
public class XYTextAnnotation extends TextAnnotation
                              implements XYAnnotation, Serializable {

    /** The x-coordinate. */
    private double x;

    /** The y-coordinate. */
    private double y;
    
    /**
     * Creates a new annotation to be displayed at the given coordinates.
     *
     * @param text  the text.
     * @param x  the x-coordinate.
     * @param y  the y-coordinate.
     */
    public XYTextAnnotation(String text, double x, double y) {
        super(text);
        this.x = x;
        this.y = y;
    }
    
    /**
     * Returns the x coordinate for the text anchor point (measured against the domain axis).
     * 
     * @return The x coordinate.
     */
    public double getX() {
        return this.x;
    }
    
    /**
     * Sets the x coordinate for the text anchor point (measured against the domain axis).
     * 
     * @param x  the x coordinate.
     */
    public void setX(double x) {
        this.x = x;
    }
    
    /**
     * Returns the y coordinate for the text anchor point (measured against the range axis).
     * 
     * @return The y coordinate.
     */
    public double getY() {
        return this.y;
    }
    
    /**
     * Sets the y coordinate for the text anchor point (measured against the range axis).
     * 
     * @param y  the y coordinate.
     */
    public void setY(double y) {
        this.y = y;
    }    

    /**
     * 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, XYPlot plot, Rectangle2D dataArea,
                     ValueAxis domainAxis, ValueAxis rangeAxis) {

        PlotOrientation orientation = plot.getOrientation();
        RectangleEdge domainEdge = Plot.resolveDomainAxisLocation(plot.getDomainAxisLocation(), 
                                                                  orientation);
        RectangleEdge rangeEdge = Plot.resolveRangeAxisLocation(plot.getRangeAxisLocation(), 
                                                                orientation);

        float anchorX = (float) domainAxis.translateValueToJava2D(this.x, dataArea, domainEdge);
        float anchorY = (float) rangeAxis.translateValueToJava2D(this.y, dataArea, rangeEdge);

        g2.setFont(getFont());
        g2.setPaint(getPaint());
        RefineryUtilities.drawRotatedString(
            getText(), 
            g2,
            anchorX, 
            anchorY,
            getTextAnchor(),
            getRotationAnchor(),
            getRotationAngle()
        );

    }

}