/* * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.swing.border; import java.awt.Graphics; import java.awt.Insets; import java.awt.Rectangle; import java.awt.Component; import java.io.Serializable; /** * A class that implements an empty border with no size. * This provides a convenient base class from which other border * classes can be easily derived. *
* Warning:
* Serialized objects of this class will not be compatible with
* future Swing releases. The current serialization support is
* appropriate for short term storage or RMI between applications running
* the same version of Swing. As of 1.4, support for long term storage
* of all JavaBeans
* has been added to the java.beans
package.
* Please see {@link java.beans.XMLEncoder}.
*
* @author David Kloba
*/
@SuppressWarnings("serial")
public abstract class AbstractBorder implements Border, Serializable
{
/**
* This default implementation does no painting.
* @param c the component for which this border is being painted
* @param g the paint graphics
* @param x the x position of the painted border
* @param y the y position of the painted border
* @param width the width of the painted border
* @param height the height of the painted border
*/
public void paintBorder(Component c, Graphics g, int x, int y, int width, int height) {
}
/**
* This default implementation returns a new {@link Insets} object
* that is initialized by the {@link #getBorderInsets(Component,Insets)}
* method.
* By default the {@code top}, {@code left}, {@code bottom},
* and {@code right} fields are set to {@code 0}.
*
* @param c the component for which this border insets value applies
* @return a new {@link Insets} object
*/
public Insets getBorderInsets(Component c) {
return getBorderInsets(c, new Insets(0, 0, 0, 0));
}
/**
* Reinitializes the insets parameter with this Border's current Insets.
* @param c the component for which this border insets value applies
* @param insets the object to be reinitialized
* @return the insets
object
*/
public Insets getBorderInsets(Component c, Insets insets) {
insets.left = insets.top = insets.right = insets.bottom = 0;
return insets;
}
/**
* This default implementation returns false.
* @return false
*/
public boolean isBorderOpaque() { return false; }
/**
* This convenience method calls the static method.
* @param c the component for which this border is being computed
* @param x the x position of the border
* @param y the y position of the border
* @param width the width of the border
* @param height the height of the border
* @return a Rectangle
containing the interior coordinates
*/
public Rectangle getInteriorRectangle(Component c, int x, int y, int width, int height) {
return getInteriorRectangle(c, this, x, y, width, height);
}
/**
* Returns a rectangle using the arguments minus the
* insets of the border. This is useful for determining the area
* that components should draw in that will not intersect the border.
* @param c the component for which this border is being computed
* @param b the Border
object
* @param x the x position of the border
* @param y the y position of the border
* @param width the width of the border
* @param height the height of the border
* @return a Rectangle
containing the interior coordinates
*/
public static Rectangle getInteriorRectangle(Component c, Border b, int x, int y, int width, int height) {
Insets insets;
if(b != null)
insets = b.getBorderInsets(c);
else
insets = new Insets(0, 0, 0, 0);
return new Rectangle(x + insets.left,
y + insets.top,
width - insets.right - insets.left,
height - insets.top - insets.bottom);
}
/**
* Returns the baseline. A return value less than 0 indicates the border
* does not have a reasonable baseline.
*
* The default implementation returns -1. Subclasses that support
* baseline should override appropriately. If a value >= 0 is
* returned, then the component has a valid baseline for any
* size >= the minimum size and getBaselineResizeBehavior
* can be used to determine how the baseline changes with size.
*
* @param c Component
baseline is being requested for
* @param width the width to get the baseline for
* @param height the height to get the baseline for
* @return the baseline or < 0 indicating there is no reasonable
* baseline
* @throws IllegalArgumentException if width or height is < 0
* @see java.awt.Component#getBaseline(int,int)
* @see java.awt.Component#getBaselineResizeBehavior()
* @since 1.6
*/
public int getBaseline(Component c, int width, int height) {
if (width < 0 || height < 0) {
throw new IllegalArgumentException(
"Width and height must be >= 0");
}
return -1;
}
/**
* Returns an enum indicating how the baseline of a component
* changes as the size changes. This method is primarily meant for
* layout managers and GUI builders.
*
* The default implementation returns
* BaselineResizeBehavior.OTHER
, subclasses that support
* baseline should override appropriately. Subclasses should
* never return null
; if the baseline can not be
* calculated return BaselineResizeBehavior.OTHER
. Callers
* should first ask for the baseline using
* getBaseline
and if a value >= 0 is returned use
* this method. It is acceptable for this method to return a
* value other than BaselineResizeBehavior.OTHER
even if
* getBaseline
returns a value less than 0.
*
* @param c Component
to return baseline resize behavior for
* @return an enum indicating how the baseline changes as the border is
* resized
* @see java.awt.Component#getBaseline(int,int)
* @see java.awt.Component#getBaselineResizeBehavior()
* @since 1.6
*/
public Component.BaselineResizeBehavior getBaselineResizeBehavior(
Component c) {
if (c == null) {
throw new NullPointerException("Component must be non-null");
}
return Component.BaselineResizeBehavior.OTHER;
}
/*
* Convenience function for determining ComponentOrientation.
* Helps us avoid having Munge directives throughout the code.
*/
static boolean isLeftToRight( Component c ) {
return c.getComponentOrientation().isLeftToRight();
}
}