Java tutorial
/* =========================================================== * JFreeChart : a free chart library for the Java(tm) platform * =========================================================== * * (C) Copyright 2000-2013, 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.] * * ---------- * Block.java * ---------- * (C) Copyright 2004-2008, by Object Refinery Limited. * * Original Author: David Gilbert (for Object Refinery Limited); * Contributor(s): -; * * Changes: * -------- * 22-Oct-2004 : Version 1 (DG); * 08-Feb-2005 : Added ID (DG); * 20-Apr-2005 : Added a new draw() method that can accept params * and return results (DG); * */ package org.jfree.chart.block; import java.awt.Graphics2D; import java.awt.geom.Rectangle2D; import org.jfree.ui.Drawable; import org.jfree.ui.Size2D; /** * A block is an arbitrary item that can be drawn (in Java2D space) within a * rectangular area, has a preferred size, and can be arranged by an * {@link Arrangement} manager. */ public interface Block extends Drawable { /** * Returns an ID for the block. * * @return An ID. */ public String getID(); /** * Sets the ID for the block. * * @param id the ID. */ public void setID(String id); /** * Arranges the contents of the block, with no constraints, and returns * the block size. * * @param g2 the graphics device. * * @return The size of the block. */ public Size2D arrange(Graphics2D g2); /** * 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</code> not permitted). * * @return The block size (in Java2D units, never <code>null</code>). */ public Size2D arrange(Graphics2D g2, RectangleConstraint constraint); /** * Returns the current bounds of the block. * * @return The bounds. */ public Rectangle2D getBounds(); /** * Sets the bounds of the block. * * @param bounds the bounds. */ public void setBounds(Rectangle2D bounds); /** * Draws the block within the specified area. Refer to the documentation * for the implementing class for information about the <code>params</code> * and return value supported. * * @param g2 the graphics device. * @param area the area. * @param params optional parameters (<code>null</code> permitted). * * @return An optional return value (possibly <code>null</code>). */ public Object draw(Graphics2D g2, Rectangle2D area, Object params); }