jfreechart example source code file (ImageTitle.java)

This example jfreechart source code file (ImageTitle.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, geometry, horizontalalignment, image, imagetitle, imagetitle, nullpointerexception, object, rectangle2d, rectangle2d, rectangleedge, rectangleedge, rectangleinsets, size2d, size2d, verticalalignment

The jfreechart ImageTitle.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.]
 *
 * ---------------
 * ImageTitle.java
 * ---------------
 * (C) Copyright 2000-2008, by David Berry and Contributors;
 *
 * Original Author:  David Berry;
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *
 * Changes (from 18-Sep-2001)
 * --------------------------
 * 18-Sep-2001 : Added standard header (DG);
 * 07-Nov-2001 : Separated the JCommon Class Library classes, JFreeChart now
 *               requires jcommon.jar (DG);
 * 09-Jan-2002 : Updated Javadoc comments (DG);
 * 07-Feb-2002 : Changed blank space around title from Insets --> Spacer, to
 *               allow for relative or absolute spacing (DG);
 * 25-Jun-2002 : Updated import statements (DG);
 * 23-Sep-2002 : Fixed errors reported by Checkstyle (DG);
 * 26-Nov-2002 : Added method for drawing images at left or right (DG);
 * 22-Sep-2003 : Added checks that the Image can never be null (TM).
 * 11-Jan-2005 : Removed deprecated code in preparation for the 1.0.0
 *               release (DG);
 * 02-Feb-2005 : Changed padding mechanism for all titles (DG);
 * 20-Apr-2005 : Added new draw() method (DG);
 * ------------- JFREECHART 1.0.x ---------------------------------------------
 * 02-Feb-2007 : Removed author tags all over JFreeChart sources (DG);
 * 11-Apr-2008 : Added arrange() method override to account for margin, border
 *               and padding (DG);
 * 21-Apr-2008 : Added equals() method override (DG);
 *
 */

package org.jfree.chart.title;

import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.geom.Rectangle2D;

import org.jfree.chart.block.RectangleConstraint;
import org.jfree.chart.event.TitleChangeEvent;
import org.jfree.ui.HorizontalAlignment;
import org.jfree.ui.RectangleEdge;
import org.jfree.ui.RectangleInsets;
import org.jfree.ui.Size2D;
import org.jfree.ui.VerticalAlignment;
import org.jfree.util.ObjectUtilities;

/**
 * A chart title that displays an image.  This is useful, for example, if you
 * have an image of your corporate logo and want to use as a footnote or part
 * of a title in a chart you create.
 * <P>
 * ImageTitle needs an image passed to it in the constructor.  For ImageTitle
 * to work, you must have already loaded this image from its source (disk or
 * URL).  It is recommended you use something like
 * Toolkit.getDefaultToolkit().getImage() to get the image.  Then, use
 * MediaTracker or some other message to make sure the image is fully loaded
 * from disk.
 * <P>
 * SPECIAL NOTE:  this class fails to serialize, so if you are
 * relying on your charts to be serializable, please avoid using this class.
 */
public class ImageTitle extends Title {

    /** The title image. */
    private Image image;

    /**
     * Creates a new image title.
     *
     * @param image  the image (<code>null not permitted).
     */
    public ImageTitle(Image image) {
        this(image, image.getHeight(null), image.getWidth(null),
                Title.DEFAULT_POSITION, Title.DEFAULT_HORIZONTAL_ALIGNMENT,
                Title.DEFAULT_VERTICAL_ALIGNMENT, Title.DEFAULT_PADDING);
    }

    /**
     * Creates a new image title.
     *
     * @param image  the image (<code>null not permitted).
     * @param position  the title position.
     * @param horizontalAlignment  the horizontal alignment.
     * @param verticalAlignment  the vertical alignment.
     */
    public ImageTitle(Image image, RectangleEdge position,
                      HorizontalAlignment horizontalAlignment,
                      VerticalAlignment verticalAlignment) {

        this(image, image.getHeight(null), image.getWidth(null),
                position, horizontalAlignment, verticalAlignment,
                Title.DEFAULT_PADDING);
    }

    /**
     * Creates a new image title with the given image scaled to the given
     * width and height in the given location.
     *
     * @param image  the image (<code>null not permitted).
     * @param height  the height used to draw the image.
     * @param width  the width used to draw the image.
     * @param position  the title position.
     * @param horizontalAlignment  the horizontal alignment.
     * @param verticalAlignment  the vertical alignment.
     * @param padding  the amount of space to leave around the outside of the
     *                 title.
     */
    public ImageTitle(Image image, int height, int width,
                      RectangleEdge position,
                      HorizontalAlignment horizontalAlignment,
                      VerticalAlignment verticalAlignment,
                      RectangleInsets padding) {

        super(position, horizontalAlignment, verticalAlignment, padding);
        if (image == null) {
            throw new NullPointerException("Null 'image' argument.");
        }
        this.image = image;
        setHeight(height);
        setWidth(width);

    }

    /**
     * Returns the image for the title.
     *
     * @return The image for the title (never <code>null).
     */
    public Image getImage() {
        return this.image;
    }

    /**
     * Sets the image for the title and notifies registered listeners that the
     * title has been modified.
     *
     * @param image  the new image (<code>null not permitted).
     */
    public void setImage(Image image) {
        if (image == null) {
            throw new NullPointerException("Null 'image' argument.");
        }
        this.image = image;
        notifyListeners(new TitleChangeEvent(this));
    }

    /**
     * Arranges the contents of the block, within the given constraints, and
     * returns the block size.
     *
     * @param g2  the graphics device.
     * @param constraint  the constraint (<code>null not permitted).
     *
     * @return The block size (in Java2D units, never <code>null).
     */
    public Size2D arrange(Graphics2D g2, RectangleConstraint constraint) {
        Size2D s = new Size2D(this.image.getWidth(null),
                this.image.getHeight(null));
        return new Size2D(calculateTotalWidth(s.getWidth()),
                calculateTotalHeight(s.getHeight()));
    }

    /**
     * Draws the title on a Java 2D graphics device (such as the screen or a
     * printer).
     *
     * @param g2  the graphics device.
     * @param area  the area allocated for the title.
     */
    public void draw(Graphics2D g2, Rectangle2D area) {
        RectangleEdge position = getPosition();
        if (position == RectangleEdge.TOP || position == RectangleEdge.BOTTOM) {
            drawHorizontal(g2, area);
        }
        else if (position == RectangleEdge.LEFT
                     || position == RectangleEdge.RIGHT) {
            drawVertical(g2, area);
        }
        else {
            throw new RuntimeException("Invalid title position.");
        }
    }

    /**
     * Draws the title on a Java 2D graphics device (such as the screen or a
     * printer).
     *
     * @param g2  the graphics device.
     * @param chartArea  the area within which the title (and plot) should be
     *                   drawn.
     *
     * @return The size of the area used by the title.
     */
    protected Size2D drawHorizontal(Graphics2D g2, Rectangle2D chartArea) {

        double startY = 0.0;
        double topSpace = 0.0;
        double bottomSpace = 0.0;
        double leftSpace = 0.0;
        double rightSpace = 0.0;

        double w = getWidth();
        double h = getHeight();
        RectangleInsets padding = getPadding();
        topSpace = padding.calculateTopOutset(h);
        bottomSpace = padding.calculateBottomOutset(h);
        leftSpace = padding.calculateLeftOutset(w);
        rightSpace = padding.calculateRightOutset(w);

        if (getPosition() == RectangleEdge.TOP) {
            startY = chartArea.getY() + topSpace;
        }
        else {
            startY = chartArea.getY() + chartArea.getHeight() - bottomSpace - h;
        }

        // what is our alignment?
        HorizontalAlignment horizontalAlignment = getHorizontalAlignment();
        double startX = 0.0;
        if (horizontalAlignment == HorizontalAlignment.CENTER) {
            startX = chartArea.getX() + leftSpace + chartArea.getWidth() / 2.0
                     - w / 2.0;
        }
        else if (horizontalAlignment == HorizontalAlignment.LEFT) {
            startX = chartArea.getX() + leftSpace;
        }
        else if (horizontalAlignment == HorizontalAlignment.RIGHT) {
            startX = chartArea.getX() + chartArea.getWidth() - rightSpace - w;
        }
        g2.drawImage(this.image, (int) startX, (int) startY, (int) w, (int) h,
                null);

        return new Size2D(chartArea.getWidth() + leftSpace + rightSpace,
            h + topSpace + bottomSpace);

    }

    /**
     * Draws the title on a Java 2D graphics device (such as the screen or a
     * printer).
     *
     * @param g2  the graphics device.
     * @param chartArea  the area within which the title (and plot) should be
     *                   drawn.
     *
     * @return The size of the area used by the title.
     */
    protected Size2D drawVertical(Graphics2D g2, Rectangle2D chartArea) {

        double startX = 0.0;
        double topSpace = 0.0;
        double bottomSpace = 0.0;
        double leftSpace = 0.0;
        double rightSpace = 0.0;

        double w = getWidth();
        double h = getHeight();

        RectangleInsets padding = getPadding();
        if (padding != null) {
            topSpace = padding.calculateTopOutset(h);
            bottomSpace = padding.calculateBottomOutset(h);
            leftSpace = padding.calculateLeftOutset(w);
            rightSpace = padding.calculateRightOutset(w);
        }

        if (getPosition() == RectangleEdge.LEFT) {
            startX = chartArea.getX() + leftSpace;
        }
        else {
            startX = chartArea.getMaxX() - rightSpace - w;
        }

        // what is our alignment?
        VerticalAlignment alignment = getVerticalAlignment();
        double startY = 0.0;
        if (alignment == VerticalAlignment.CENTER) {
            startY = chartArea.getMinY() + topSpace
                     + chartArea.getHeight() / 2.0 - h / 2.0;
        }
        else if (alignment == VerticalAlignment.TOP) {
            startY = chartArea.getMinY() + topSpace;
        }
        else if (alignment == VerticalAlignment.BOTTOM) {
            startY = chartArea.getMaxY() - bottomSpace - h;
        }

        g2.drawImage(this.image, (int) startX, (int) startY, (int) w, (int) h,
                null);

        return new Size2D(chartArea.getWidth() + leftSpace + rightSpace,
            h + topSpace + bottomSpace);

    }

    /**
     * Draws the block within the specified area.
     *
     * @param g2  the graphics device.
     * @param area  the area.
     * @param params  ignored (<code>null permitted).
     *
     * @return Always <code>null.
     */
    public Object draw(Graphics2D g2, Rectangle2D area, Object params) {
        draw(g2, area);
        return null;
    }

    /**
     * Tests this <code>ImageTitle for equality with an arbitrary
     * object.  Returns <code>true if:
     * <ul>
     * <li>obj is an instance of ImageTitle;
     * <li>obj references the same image as this
     *     <code>ImageTitle;
     * <li>super.equals(obj) returns true;
     * </ul>
     *
     * @param obj  the object (<code>null permitted).
     *
     * @return A boolean.
     */
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof ImageTitle)) {
            return false;
        }
        ImageTitle that = (ImageTitle) obj;
        if (!ObjectUtilities.equal(this.image, that.image)) {
            return false;
        }
        return super.equals(obj);
    }

}