Java tutorial
/* =========================================================== * JFreeChart : a free chart library for the Java(tm) platform * =========================================================== * * (C) Copyright 2000-2006, 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.] * * ------------------- * DialBackground.java * ------------------- * (C) Copyright 2006, by Object Refinery Limited. * * Original Author: David Gilbert (for Object Refinery Limited); * Contributor(s): -; * * $Id: DialBackground.java,v 1.1.2.2 2006/11/06 16:26:06 mungady Exp $ * * Changes * ------- * 03-Nov-2006 : Version 1 (DG); * */ package org.jfree.experimental.chart.plot.dial; import java.awt.Color; import java.awt.GradientPaint; import java.awt.Graphics2D; import java.awt.Paint; 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.io.SerialUtilities; import org.jfree.ui.GradientPaintTransformer; import org.jfree.ui.StandardGradientPaintTransformer; import org.jfree.util.PaintUtilities; import org.jfree.util.PublicCloneable; /** * A regular dial layer that can be used to draw the background for a dial. */ public class DialBackground extends AbstractDialLayer implements DialLayer, Cloneable, PublicCloneable, Serializable { /** * The background paint. This field is transient because serialization * requires special handling. */ private transient Paint paint; /** * The transformer used when the background paint is an instance of * <code>GradientPaint</code>. */ private GradientPaintTransformer gradientPaintTransformer; /** * Creates a new instance of <code>DialBackground</code>. The * default background paint is <code>Color.white</code>. */ public DialBackground() { this(Color.white); } /** * Creates a new instance of <code>DialBackground</code>. The * * @param paint the paint (<code>null</code> not permitted). * * @throws IllegalArgumentException if <code>paint</code> is * <code>null</code>. */ public DialBackground(Paint paint) { if (paint == null) { throw new IllegalArgumentException("Null 'paint' argument."); } this.paint = paint; this.gradientPaintTransformer = new StandardGradientPaintTransformer(); } /** * Returns the paint used to fill the background. * * @return The paint (never <code>null</code>). * * @see #setPaint(Paint) */ public Paint getPaint() { return this.paint; } /** * Sets the paint for the dial background. * * @param paint the paint (<code>null</code> not permitted). * * @see #getPaint() */ public void setPaint(Paint paint) { if (paint == null) { throw new IllegalArgumentException("Null 'paint' argument."); } this.paint = paint; notifyListeners(new DialLayerChangeEvent(this)); } /** * Returns the transformer used to adjust the coordinates of any * <code>GradientPaint</code> instance used for the background paint. * * @return The transformer (never <code>null</code>). * * @see #setGradientPaintTransformer(GradientPaintTransformer) */ public GradientPaintTransformer getGradientPaintTransformer() { return this.gradientPaintTransformer; } /** * Sets the transformer used to adjust the coordinates of any * <code>GradientPaint</code> instance used for the background paint. * * @param t the transformer (<code>null</code> not permitted). * * @see #getGradientPaintTransformer() */ public void setGradientPaintTransformer(GradientPaintTransformer t) { if (t == null) { throw new IllegalArgumentException("Null 't' argument."); } this.gradientPaintTransformer = t; notifyListeners(new DialLayerChangeEvent(this)); } /** * Returns <code>true</code> to indicate that this layer should be * clipped within the dial window. * * @return <code>true</code>. */ public boolean isClippedToWindow() { return true; } /** * Draws the background to the specified graphics device. If the dial * frame specifies a window, the clipping region will already have been * set to this window before this method is called. * * @param g2 the graphics device (<code>null</code> not permitted). * @param plot the plot (ignored here). * @param frame the dial frame (ignored here). * @param view the view rectangle (<code>null</code> not permitted). */ public void draw(Graphics2D g2, DialPlot plot, Rectangle2D frame, Rectangle2D view) { Paint p = this.paint; if (p instanceof GradientPaint) { p = this.gradientPaintTransformer.transform((GradientPaint) p, view); } g2.setPaint(p); g2.fill(view); } /** * Tests this instance for equality with an arbitrary object. * * @param obj the object (<code>null</code> permitted). * * @return A boolean. */ public boolean equals(Object obj) { if (obj == this) { return true; } if (!(obj instanceof DialBackground)) { return false; } DialBackground that = (DialBackground) obj; if (!PaintUtilities.equal(this.paint, that.paint)) { return false; } if (!this.gradientPaintTransformer.equals(that.gradientPaintTransformer)) { return false; } return true; } /** * Returns a hash code for this instance. * * @return The hash code. */ public int hashCode() { int result = 193; result = 37 * result + HashUtilities.hashCodeForPaint(paint); result = 37 * result + this.gradientPaintTransformer.hashCode(); return result; } /** * Returns a clone of this instance. * * @return The clone. * * @throws CloneNotSupportedException if some attribute of this instance * cannot 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.paint, 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.paint = SerialUtilities.readPaint(stream); } }