| /* AbstractBorder.java -- |
| Copyright (C) 2003, 2006, Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package javax.swing.border; |
| |
| import java.awt.Component; |
| import java.awt.Graphics; |
| import java.awt.Insets; |
| import java.awt.Rectangle; |
| import java.io.Serializable; |
| |
| |
| /** |
| * An invisible zero-width border, serving as a base class for |
| * implementing more interesting borders. |
| * |
| * @author Sascha Brawer (brawer@dandelis.ch) |
| * @author Ronald Veldema (rveldema@cs.vu.nl) |
| */ |
| public abstract class AbstractBorder implements Border, Serializable |
| { |
| static final long serialVersionUID = -545885975315191844L; |
| |
| /** |
| * Constructs a new AbstractBorder. |
| */ |
| public AbstractBorder() |
| { |
| // Nothing to do here. |
| } |
| |
| /** |
| * Performs nothing, because the default implementation provided by |
| * this class is an invisible, zero-width border. Subclasses will |
| * likely want to override this method, but they are not required |
| * to do so. |
| * |
| * @param c the component whose border is to be painted. |
| * @param g the graphics for painting. |
| * @param x the horizontal position for painting the border. |
| * @param y the vertical position for painting the border. |
| * @param width the width of the available area for painting the border. |
| * @param height the height of the available area for painting the border. |
| */ |
| public void paintBorder(Component c, Graphics g, int x, int y, int width, |
| int height) |
| { |
| // A previous version of Classpath had emitted a warning when |
| // this method was called. The warning was removed because it is |
| // perfectly legal for a subclass to not override the paintBorder |
| // method. An example would be EmptyBorder. |
| } |
| |
| /** |
| * Returns the insets required for drawing this border around the specified |
| * component. |
| * |
| * @param c the component that the border applies to (ignored here, |
| * subclasses may use it). |
| * |
| * @return an Insets object whose <code>left</code>, <code>right</code>, |
| * <code>top</code> and <code>bottom</code> fields indicate the |
| * width of the border at the respective edge, which is zero |
| * for the default implementation provided by AbstractButton. |
| * |
| * @see #getBorderInsets(java.awt.Component, java.awt.Insets) |
| */ |
| public Insets getBorderInsets(Component c) |
| { |
| return new Insets(0, 0, 0, 0); |
| } |
| |
| /** |
| * Returns the insets required for drawing this border around the specified |
| * component. The default implementation provided here sets the |
| * <code>left</code>, <code>right</code>, <code>top</code> and |
| * <code>bottom</code> fields of the passed <code>insets</code> parameter to |
| * zero. |
| * |
| * @param c the component that the border applies to (ignored here, |
| * subclasses may use it). |
| * @param insets an instance that will be overwritten and returned as the |
| * result (<code>null</code> not permitted). |
| * |
| * @return The border insets (the same object that was passed as the |
| * <code>insets</code> argument). |
| * |
| * @see #getBorderInsets(Component) |
| * |
| * @throws NullPointerException if <code>insets</code> is <code>null</code>. |
| */ |
| public Insets getBorderInsets(Component c, Insets insets) |
| { |
| insets.left = insets.right = insets.top = insets.bottom = 0; |
| return insets; |
| } |
| |
| /** |
| * Determines whether or not this border is opaque. An opaque border |
| * fills every pixel in its area when painting. Partially |
| * translucent borders must return <code>false</code>, or ugly |
| * artifacts can appear on screen. The default implementation |
| * provided here always returns <code>false</code>. |
| * |
| * @return <code>false</code>. |
| */ |
| public boolean isBorderOpaque() |
| { |
| return false; |
| } |
| |
| /** |
| * Returns a rectangle that covers the specified area minus the insets |
| * required to draw this border. Components that wish to determine an area |
| * into which they can safely draw without intersecting with a border might |
| * want to use this helper method. |
| * |
| * @param c the component in the center of this border. |
| * @param x the horizontal position of the border. |
| * @param y the vertical position of the border. |
| * @param width the width of the available area for the border. |
| * @param height the height of the available area for the border. |
| * |
| * @return The interior rectangle. |
| */ |
| public Rectangle getInteriorRectangle(Component c, int x, int y, int width, |
| int height) |
| { |
| return getInteriorRectangle(c, this, x, y, width, height); |
| } |
| |
| /** |
| * Returns a rectangle that covers the specified area minus the insets |
| * required to draw the specified border (if the border is <code>null</code>, |
| * zero insets are assumed). Components that wish to determine an area into |
| * which they can safely draw without intersecting with a border might want |
| * to use this helper method. |
| * |
| * @param c the component in the center of this border. |
| * @param b the border (<code>null</code> permitted). |
| * @param x the horizontal position of the border. |
| * @param y the vertical position of the border. |
| * @param width the width of the available area for the border. |
| * @param height the height of the available area for the border. |
| * |
| * @return The interior rectangle. |
| */ |
| public static Rectangle getInteriorRectangle(Component c, Border b, int x, |
| int y, int width, int height) |
| { |
| Insets borderInsets; |
| |
| if (b != null) |
| { |
| borderInsets = b.getBorderInsets(c); |
| x += borderInsets.left; |
| y += borderInsets.top; |
| width -= borderInsets.left + borderInsets.right; |
| height -= borderInsets.top + borderInsets.bottom; |
| } |
| |
| return new Rectangle(x, y, width, height); |
| } |
| } |