Java tutorial
/* =========================================================== * JFreeChart : a free chart library for the Java(tm) platform * =========================================================== * * (C) Copyright 2000-2014, 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. * * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. * Other names may be trademarks of their respective owners.] * * --------------- * ImageTitle.java * --------------- * (C) Copyright 2000-2014, 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}). */ @Override 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. */ @Override 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; double topSpace; double bottomSpace; double leftSpace; double rightSpace; 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; 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}. */ @Override 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>{@code obj} is an instance of {@code ImageTitle}; * <li>{@code obj} references the same image as this * {@code ImageTitle}; * <li>{@code super.equals(obj)} returns {@code true}; * </ul> * * @param obj the object ({@code null} permitted). * * @return A boolean. */ @Override 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); } }