001 /* Dimension.java -- represents a 2-dimensional span 002 Copyright (C) 1999, 2000, 2002 Free Software Foundation 003 004 This file is part of GNU Classpath. 005 006 GNU Classpath is free software; you can redistribute it and/or modify 007 it under the terms of the GNU General Public License as published by 008 the Free Software Foundation; either version 2, or (at your option) 009 any later version. 010 011 GNU Classpath is distributed in the hope that it will be useful, but 012 WITHOUT ANY WARRANTY; without even the implied warranty of 013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014 General Public License for more details. 015 016 You should have received a copy of the GNU General Public License 017 along with GNU Classpath; see the file COPYING. If not, write to the 018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 019 02110-1301 USA. 020 021 Linking this library statically or dynamically with other modules is 022 making a combined work based on this library. Thus, the terms and 023 conditions of the GNU General Public License cover the whole 024 combination. 025 026 As a special exception, the copyright holders of this library give you 027 permission to link this library with independent modules to produce an 028 executable, regardless of the license terms of these independent 029 modules, and to copy and distribute the resulting executable under 030 terms of your choice, provided that you also meet, for each linked 031 independent module, the terms and conditions of the license of that 032 module. An independent module is a module which is not derived from 033 or based on this library. If you modify this library, you may extend 034 this exception to your version of the library, but you are not 035 obligated to do so. If you do not wish to do so, delete this 036 exception statement from your version. */ 037 038 039 package java.awt; 040 041 import java.awt.geom.Dimension2D; 042 import java.io.Serializable; 043 044 /** 045 * This class holds a width and height value pair. This is used in plenty 046 * of windowing classes, but also has geometric meaning. 047 * 048 * <p>It is valid for a dimension to have negative width or height; but it 049 * is considered to have no area. Therefore, the behavior in various methods 050 * is undefined in such a case. 051 * 052 * <p>There are some public fields; if you mess with them in an inconsistent 053 * manner, it is your own fault when you get invalid results. Also, this 054 * class is not threadsafe. 055 * 056 * @author Per Bothner (bothner@cygnus.com) 057 * @author Aaron M. Renn (arenn@urbanophile.com) 058 * @author Eric Blake (ebb9@email.byu.edu) 059 * @see Component 060 * @see LayoutManager 061 * @since 1.0 062 * @status updated to 1.14 063 */ 064 public class Dimension extends Dimension2D implements Serializable 065 { 066 /** 067 * Compatible with JDK 1.0+. 068 */ 069 private static final long serialVersionUID = 4723952579491349524L; 070 071 /** 072 * The width of this object. 073 * 074 * @see #getSize() 075 * @see #setSize(double, double) 076 * @serial the width 077 */ 078 public int width; 079 080 /** 081 * The height of this object. 082 * 083 * @see #getSize() 084 * @see #setSize(double, double) 085 * @serial the height 086 */ 087 public int height; 088 089 /** 090 * Create a new Dimension with a width and height of zero. 091 */ 092 public Dimension() 093 { 094 } 095 096 /** 097 * Create a new Dimension with width and height identical to that of the 098 * specified dimension. 099 * 100 * @param d the Dimension to copy 101 * @throws NullPointerException if d is null 102 */ 103 public Dimension(Dimension d) 104 { 105 width = d.width; 106 height = d.height; 107 } 108 109 /** 110 * Create a new Dimension with the specified width and height. 111 * 112 * @param w the width of this object 113 * @param h the height of this object 114 */ 115 public Dimension(int w, int h) 116 { 117 width = w; 118 height = h; 119 } 120 121 /** 122 * Gets the width of this dimension. 123 * 124 * @return the width, as a double 125 */ 126 public double getWidth() 127 { 128 return width; 129 } 130 131 /** 132 * Gets the height of this dimension. 133 * 134 * @return the height, as a double 135 */ 136 public double getHeight() 137 { 138 return height; 139 } 140 141 /** 142 * Sets the size of this dimension. The values are rounded to int. 143 * 144 * @param w the new width 145 * @param h the new height 146 * @since 1.2 147 */ 148 public void setSize(double w, double h) 149 { 150 width = (int) w; 151 height = (int) h; 152 } 153 154 /** 155 * Returns the size of this dimension. A pretty useless method, as this is 156 * already a dimension. 157 * 158 * @return a copy of this dimension 159 * @see #setSize(Dimension) 160 * @since 1.1 161 */ 162 public Dimension getSize() 163 { 164 return new Dimension(width, height); 165 } 166 167 /** 168 * Sets the width and height of this object to match that of the 169 * specified object. 170 * 171 * @param d the Dimension to get the new width and height from 172 * @throws NullPointerException if d is null 173 * @see #getSize() 174 * @since 1.1 175 */ 176 public void setSize(Dimension d) 177 { 178 width = d.width; 179 height = d.height; 180 } 181 182 /** 183 * Sets the width and height of this object to the specified values. 184 * 185 * @param w the new width value 186 * @param h the new height value 187 */ 188 public void setSize(int w, int h) 189 { 190 width = w; 191 height = h; 192 } 193 194 /** 195 * Tests this object for equality against the specified object. This will 196 * be true if and only if the specified object is an instance of 197 * Dimension2D, and has the same width and height. 198 * 199 * @param obj the object to test against 200 * @return true if the object is equal to this 201 */ 202 public boolean equals(Object obj) 203 { 204 if (! (obj instanceof Dimension)) 205 return false; 206 Dimension dim = (Dimension) obj; 207 return height == dim.height && width == dim.width; 208 } 209 210 /** 211 * Return the hashcode for this object. It is not documented, but appears 212 * to be <code>((width + height) * (width + height + 1) / 2) + width</code>. 213 * 214 * @return the hashcode 215 */ 216 public int hashCode() 217 { 218 // Reverse engineering this was fun! 219 return (width + height) * (width + height + 1) / 2 + width; 220 } 221 222 /** 223 * Returns a string representation of this object. The format is: 224 * <code>getClass().getName() + "[width=" + width + ",height=" + height 225 * + ']'</code>. 226 * 227 * @return a string representation of this object 228 */ 229 public String toString() 230 { 231 return getClass().getName() 232 + "[width=" + width + ",height=" + height + ']'; 233 } 234 } // class Dimension