diff options
Diffstat (limited to 'libjava/javax/swing/border/AbstractBorder.java')
| -rw-r--r-- | libjava/javax/swing/border/AbstractBorder.java | 194 |
1 files changed, 129 insertions, 65 deletions
diff --git a/libjava/javax/swing/border/AbstractBorder.java b/libjava/javax/swing/border/AbstractBorder.java index fad3aa288ef..663fb1130e0 100644 --- a/libjava/javax/swing/border/AbstractBorder.java +++ b/libjava/javax/swing/border/AbstractBorder.java @@ -1,5 +1,5 @@ /* AbstractBorder.java -- - Copyright (C) 2002 Free Software Foundation, Inc. + Copyright (C) 2003 Free Software Foundation, Inc. This file is part of GNU Classpath. @@ -44,85 +44,149 @@ import java.awt.Insets; import java.awt.Rectangle; import java.io.Serializable; -public abstract class AbstractBorder implements Border, 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 () { } - public void paintBorder(Component c, - Graphics g, - int x, - int y, - int width, - int height) - { - System.out.println("HMMMMM, abstract-border.paintBorder"); - } + /** + * 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 + * for doing 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. + */ + } - public Insets getBorderInsets(Component c, Insets insets) - { - if (insets == null) - insets = new Insets(0,0,0,0); - - insets.left = insets.top = insets.right = insets.bottom = 5; - return insets; - } + /** + * Determines the insets of this border. The implementation provided + * by AbstractButton returns Insets for a zero-width border, whose + * <code>left</code>, <code>right</code>, <code>top</code> and + * <code>bottom</code> fields are all zero. + * + * @param c the component whose border is to be measured. + * + * @return a newly created Insets object, indicating a zero-width + * border. + */ + public Insets getBorderInsets (Component c) + { + return new Insets (0, 0, 0, 0); + } - public Insets getBorderInsets(Component c) - { - return getBorderInsets(c, new Insets(0,0,0,0)); - } + /** + * Determines the insets of this border. The implementation provided + * by AbstractButton 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 in the center of this border. + * + * @param insets an Insets object for holding the insets of this + * border. + * + * @return the <code>insets</code> object. + */ + public Insets getBorderInsets (Component c, Insets insets) + { + insets.left = insets.right = insets.top = insets.bottom = 0; + return insets; + } - public boolean isBorderOpaque() - { return false; } - public Rectangle getInteriorRectangle(Component c, - int x, - int y, - int width, - int height) - { - return getInteriorRectangle(c, - this, - x, - y, - width, - height); - } + /** + * 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 by AbstractBorder always returns <code>false</code>. + * + * @return <code>false</code>. + */ + public boolean isBorderOpaque () + { + return false; + } - - public static Rectangle getInteriorRectangle(Component c, - Border b, - int x, - int y, - int width, - int height) + + /** + * Returns a rectangle that covers the specified area minus 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. + */ + 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 a + * 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. + */ + public static Rectangle getInteriorRectangle (Component c, Border b, + int x, int y, int width, int height) + { + Insets borderInsets; + + if (b != null) { - if(b != null) - { - Insets insets = b.getBorderInsets(c); - - int w = insets.right - insets.left; - int h = insets.top - insets.bottom; - - return new Rectangle(x + insets.left, - y + insets.top, - width - w, - height - h); - } - else - { - return new Rectangle(x, - y, - width, - height); - } + 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); + } +} |
