001 /* Shape.java -- the classic Object-Oriented shape interface 002 Copyright (C) 1999, 2002, 2005, 2006, Free Software Foundation, Inc. 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.AffineTransform; 042 import java.awt.geom.PathIterator; 043 import java.awt.geom.Point2D; 044 import java.awt.geom.Rectangle2D; 045 046 /** 047 * This interface represents an abstract shape. The shape is described by 048 * a {@link PathIterator}, and has callbacks for determining bounding box, 049 * where points and rectangles lie in relation to the shape, and tracing 050 * the trajectory. 051 * 052 * <p>A point is inside if it is completely inside, or on the boundary and 053 * adjacent points in the increasing x or y direction are completely inside. 054 * Unclosed shapes are considered as implicitly closed when performing 055 * <code>contains</code> or <code>intersects</code>. 056 * 057 * @author Aaron M. Renn (arenn@urbanophile.com) 058 * @see PathIterator 059 * @see AffineTransform 060 * @see java.awt.geom.FlatteningPathIterator 061 * @see java.awt.geom.GeneralPath 062 * @since 1.0 063 * @status updated to 1.4 064 */ 065 public interface Shape 066 { 067 /** 068 * Returns a <code>Rectange</code> that bounds the shape. There is no 069 * guarantee that this is the minimum bounding box, particularly if 070 * the shape overflows the finite integer range of a bound. Generally, 071 * <code>getBounds2D</code> returns a tighter bound. 072 * 073 * @return the shape's bounding box 074 * @see #getBounds2D() 075 */ 076 Rectangle getBounds(); 077 078 /** 079 * Returns a high precision bounding box of the shape. There is no guarantee 080 * that this is the minimum bounding box, but at least it never overflows. 081 * 082 * @return the shape's bounding box 083 * @see #getBounds() 084 * @since 1.2 085 */ 086 Rectangle2D getBounds2D(); 087 088 /** 089 * Test if the coordinates lie in the shape. 090 * 091 * @param x the x coordinate 092 * @param y the y coordinate 093 * @return true if (x,y) lies inside the shape 094 * @since 1.2 095 */ 096 boolean contains(double x, double y); 097 098 /** 099 * Test if the point lie in the shape. 100 * 101 * @param p the high-precision point 102 * @return true if p lies inside the shape 103 * @throws NullPointerException if p is null 104 * @since 1.2 105 */ 106 boolean contains(Point2D p); 107 108 /** 109 * Test if a high-precision rectangle intersects the shape. This is true 110 * if any point in the rectangle is in the shape, with the caveat that the 111 * operation may include high probability estimates when the actual 112 * calculation is prohibitively expensive. The {@link java.awt.geom.Area} 113 * class can be used for more precise answers. 114 * 115 * @param x the x coordinate of the rectangle 116 * @param y the y coordinate of the rectangle 117 * @param w the width of the rectangle, undefined results if negative 118 * @param h the height of the rectangle, undefined results if negative 119 * @return true if the rectangle intersects this shape 120 * @see java.awt.geom.Area 121 * @since 1.2 122 */ 123 boolean intersects(double x, double y, double w, double h); 124 125 /** 126 * Test if a high-precision rectangle intersects the shape. This is true 127 * if any point in the rectangle is in the shape, with the caveat that the 128 * operation may include high probability estimates when the actual 129 * calculation is prohibitively expensive. The {@link java.awt.geom.Area} 130 * class can be used for more precise answers. 131 * 132 * @param r the rectangle 133 * @return true if the rectangle intersects this shape 134 * @throws NullPointerException if r is null 135 * @see #intersects(double, double, double, double) 136 * @since 1.2 137 */ 138 boolean intersects(Rectangle2D r); 139 140 /** 141 * Test if a high-precision rectangle lies completely in the shape. This is 142 * true if all points in the rectangle are in the shape, with the caveat 143 * that the operation may include high probability estimates when the actual 144 * calculation is prohibitively expensive. The {@link java.awt.geom.Area} 145 * class can be used for more precise answers. 146 * 147 * @param x the x coordinate of the rectangle 148 * @param y the y coordinate of the rectangle 149 * @param w the width of the rectangle, undefined results if negative 150 * @param h the height of the rectangle, undefined results if negative 151 * @return true if the rectangle is contained in this shape 152 * @see java.awt.geom.Area 153 * @since 1.2 154 */ 155 boolean contains(double x, double y, double w, double h); 156 157 /** 158 * Test if a high-precision rectangle lies completely in the shape. This is 159 * true if all points in the rectangle are in the shape, with the caveat 160 * that the operation may include high probability estimates when the actual 161 * calculation is prohibitively expensive. The {@link java.awt.geom.Area} 162 * class can be used for more precise answers. 163 * 164 * @param r the rectangle 165 * @return true if the rectangle is contained in this shape 166 * @throws NullPointerException if r is null 167 * @see #contains(double, double, double, double) 168 * @since 1.2 169 */ 170 boolean contains(Rectangle2D r); 171 172 /** 173 * Return an iterator along the shape boundary. If the optional transform 174 * is provided, the iterator is transformed accordingly. Each call returns 175 * a new object, independent from others in use. It is recommended, but 176 * not required, that the Shape isolate iterations from future changes to 177 * the boundary, and document this fact. 178 * 179 * @param transform an optional transform to apply to the 180 * iterator (<code>null</code> permitted). 181 * @return a new iterator over the boundary 182 * @since 1.2 183 */ 184 PathIterator getPathIterator(AffineTransform transform); 185 186 /** 187 * Return an iterator along the flattened version of the shape boundary. 188 * Only SEG_MOVETO, SEG_LINETO, and SEG_CLOSE points are returned in the 189 * iterator. The flatness parameter controls how far points are allowed to 190 * differ from the real curve; although a limit on accuracy may cause this 191 * parameter to be enlarged if needed. 192 * 193 * <p>If the optional transform is provided, the iterator is transformed 194 * accordingly. Each call returns a new object, independent from others in 195 * use. It is recommended, but not required, that the Shape isolate 196 * iterations from future changes to the boundary, and document this fact. 197 * 198 * @param transform an optional transform to apply to the 199 * iterator (<code>null</code> permitted). 200 * @param flatness the maximum distance for deviation from the real boundary 201 * @return a new iterator over the boundary 202 * @since 1.2 203 */ 204 PathIterator getPathIterator(AffineTransform transform, double flatness); 205 }