jdk/src/share/classes/javax/swing/border/AbstractBorder.java
changeset 2 90ce3da70b43
child 5506 202f599c92aa
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/javax/swing/border/AbstractBorder.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,198 @@
+/*
+ * Copyright 1997-2006 Sun Microsystems, Inc.  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.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.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.
+ * <p>
+ * <strong>Warning:</strong>
+ * 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<sup><font size="-2">TM</font></sup>
+ * has been added to the <code>java.beans</code> package.
+ * Please see {@link java.beans.XMLEncoder}.
+ *
+ * @author David Kloba
+ */
+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 <code>insets</code> 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 <code>Rectangle</code> 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 <code>Border</code> 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 <code>Rectangle</code> 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.
+     * <p>
+     * The default implementation returns -1.  Subclasses that support
+     * baseline should override appropriately.  If a value &gt;= 0 is
+     * returned, then the component has a valid baseline for any
+     * size &gt;= the minimum size and <code>getBaselineResizeBehavior</code>
+     * can be used to determine how the baseline changes with size.
+     *
+     * @param c <code>Component</code> 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 &lt; 0 indicating there is no reasonable
+     *         baseline
+     * @throws IllegalArgumentException if width or height is &lt; 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.
+     * <p>
+     * The default implementation returns
+     * <code>BaselineResizeBehavior.OTHER</code>, subclasses that support
+     * baseline should override appropriately.  Subclasses should
+     * never return <code>null</code>; if the baseline can not be
+     * calculated return <code>BaselineResizeBehavior.OTHER</code>.  Callers
+     * should first ask for the baseline using
+     * <code>getBaseline</code> and if a value &gt;= 0 is returned use
+     * this method.  It is acceptable for this method to return a
+     * value other than <code>BaselineResizeBehavior.OTHER</code> even if
+     * <code>getBaseline</code> returns a value less than 0.
+     *
+     * @param c <code>Component</code> 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();
+    }
+
+}