Java tutorial
/* * Copyright (c) 1997, 2015, 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.Color; import java.awt.Component; import java.awt.Graphics2D; import java.awt.Shape; import java.awt.geom.Path2D; import java.awt.geom.Rectangle2D; import java.awt.geom.RoundRectangle2D; import java.beans.ConstructorProperties; /** * A class which implements a line border of arbitrary thickness * and of a single color. * <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™ * has been added to the <code>java.beans</code> package. * Please see {@link java.beans.XMLEncoder}. * * @author David Kloba */ @SuppressWarnings("serial") // Same-version serialization only public class LineBorder extends AbstractBorder { private static Border blackLine; private static Border grayLine; /** * Thickness of the border. */ protected int thickness; /** * Color of the border. */ protected Color lineColor; /** * Whether or not the border has rounded corners. */ protected boolean roundedCorners; /** * Convenience method for getting the Color.black LineBorder of thickness 1. * * @return a {@code LineBorder} with {@code Color.black} and thickness of 1 */ public static Border createBlackLineBorder() { if (blackLine == null) { blackLine = new LineBorder(Color.black, 1); } return blackLine; } /** * Convenience method for getting the Color.gray LineBorder of thickness 1. * * @return a {@code LineBorder} with {@code Color.gray} and thickness of 1 */ public static Border createGrayLineBorder() { if (grayLine == null) { grayLine = new LineBorder(Color.gray, 1); } return grayLine; } /** * Creates a line border with the specified color and a * thickness = 1. * * @param color the color for the border */ public LineBorder(Color color) { this(color, 1, false); } /** * Creates a line border with the specified color and thickness. * * @param color the color of the border * @param thickness the thickness of the border */ public LineBorder(Color color, int thickness) { this(color, thickness, false); } /** * Creates a line border with the specified color, thickness, * and corner shape. * * @param color the color of the border * @param thickness the thickness of the border * @param roundedCorners whether or not border corners should be round * @since 1.3 */ @ConstructorProperties({ "lineColor", "thickness", "roundedCorners" }) public LineBorder(Color color, int thickness, boolean roundedCorners) { lineColor = color; this.thickness = thickness; this.roundedCorners = roundedCorners; } /** * Paints the border for the specified component with the * specified position and size. * * @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) { if ((this.thickness > 0) && (g instanceof Graphics2D)) { Graphics2D g2d = (Graphics2D) g; Color oldColor = g2d.getColor(); g2d.setColor(this.lineColor); Shape outer; Shape inner; int offs = this.thickness; int size = offs + offs; if (this.roundedCorners) { float arc = .2f * offs; outer = new RoundRectangle2D.Float(x, y, width, height, offs, offs); inner = new RoundRectangle2D.Float(x + offs, y + offs, width - size, height - size, arc, arc); } else { outer = new Rectangle2D.Float(x, y, width, height); inner = new Rectangle2D.Float(x + offs, y + offs, width - size, height - size); } Path2D path = new Path2D.Float(Path2D.WIND_EVEN_ODD); path.append(outer, false); path.append(inner, false); g2d.fill(path); g2d.setColor(oldColor); } } /** * Reinitialize 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 */ public Insets getBorderInsets(Component c, Insets insets) { insets.set(thickness, thickness, thickness, thickness); return insets; } /** * Returns the color of the border. * * @return a {@code Color} object representing the color of this object */ public Color getLineColor() { return lineColor; } /** * Returns the thickness of the border. * * @return the thickness of this border */ public int getThickness() { return thickness; } /** * Returns whether this border will be drawn with rounded corners. * * @return {@code true} if this border should have rounded corners * @since 1.3 */ public boolean getRoundedCorners() { return roundedCorners; } /** * Returns whether or not the border is opaque. * * @return {@code true} if the border is opaque, {@code false} otherwise */ public boolean isBorderOpaque() { return !roundedCorners; } }