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1   /*
2    * Copyright (c) 1997, Oracle and/or its affiliates. All rights reserved.
3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4    *
5    * This code is free software; you can redistribute it and/or modify it
6    * under the terms of the GNU General Public License version 2 only, as
7    * published by the Free Software Foundation.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14   * version 2 for more details (a copy is included in the LICENSE file that
15   * accompanied this code).
16   *
17   * You should have received a copy of the GNU General Public License version
18   * 2 along with this work; if not, write to the Free Software Foundation,
19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  
26  package java.awt.geom;
27  
28  import java.util.*;
29  
30  /**
31   * A utility class to iterate over the path segments of a rectangle
32   * through the PathIterator interface.
33   *
34   * @author      Jim Graham
35   */
36  class RectIterator implements PathIterator {
37      double x, y, w, h;
38      AffineTransform affine;
39      int index;
40  
41      RectIterator(Rectangle2D r, AffineTransform at) {
42          this.x = r.getX();
43          this.y = r.getY();
44          this.w = r.getWidth();
45          this.h = r.getHeight();
46          this.affine = at;
47          if (w < 0 || h < 0) {
48              index = 6;
49          }
50      }
51  
52      /**
53       * Return the winding rule for determining the insideness of the
54       * path.
55       * @see #WIND_EVEN_ODD
56       * @see #WIND_NON_ZERO
57       */
58      public int getWindingRule() {
59          return WIND_NON_ZERO;
60      }
61  
62      /**
63       * Tests if there are more points to read.
64       * @return true if there are more points to read
65       */
66      public boolean isDone() {
67          return index > 5;
68      }
69  
70      /**
71       * Moves the iterator to the next segment of the path forwards
72       * along the primary direction of traversal as long as there are
73       * more points in that direction.
74       */
75      public void next() {
76          index++;
77      }
78  
79      /**
80       * Returns the coordinates and type of the current path segment in
81       * the iteration.
82       * The return value is the path segment type:
83       * SEG_MOVETO, SEG_LINETO, SEG_QUADTO, SEG_CUBICTO, or SEG_CLOSE.
84       * A float array of length 6 must be passed in and may be used to
85       * store the coordinates of the point(s).
86       * Each point is stored as a pair of float x,y coordinates.
87       * SEG_MOVETO and SEG_LINETO types will return one point,
88       * SEG_QUADTO will return two points,
89       * SEG_CUBICTO will return 3 points
90       * and SEG_CLOSE will not return any points.
91       * @see #SEG_MOVETO
92       * @see #SEG_LINETO
93       * @see #SEG_QUADTO
94       * @see #SEG_CUBICTO
95       * @see #SEG_CLOSE
96       */
97      public int currentSegment(float[] coords) {
98          if (isDone()) {
99              throw new NoSuchElementException("rect iterator out of bounds");
100         }
101         if (index == 5) {
102             return SEG_CLOSE;
103         }
104         coords[0] = (float) x;
105         coords[1] = (float) y;
106         if (index == 1 || index == 2) {
107             coords[0] += (float) w;
108         }
109         if (index == 2 || index == 3) {
110             coords[1] += (float) h;
111         }
112         if (affine != null) {
113             affine.transform(coords, 0, coords, 0, 1);
114         }
115         return (index == 0 ? SEG_MOVETO : SEG_LINETO);
116     }
117 
118     /**
119      * Returns the coordinates and type of the current path segment in
120      * the iteration.
121      * The return value is the path segment type:
122      * SEG_MOVETO, SEG_LINETO, SEG_QUADTO, SEG_CUBICTO, or SEG_CLOSE.
123      * A double array of length 6 must be passed in and may be used to
124      * store the coordinates of the point(s).
125      * Each point is stored as a pair of double x,y coordinates.
126      * SEG_MOVETO and SEG_LINETO types will return one point,
127      * SEG_QUADTO will return two points,
128      * SEG_CUBICTO will return 3 points
129      * and SEG_CLOSE will not return any points.
130      * @see #SEG_MOVETO
131      * @see #SEG_LINETO
132      * @see #SEG_QUADTO
133      * @see #SEG_CUBICTO
134      * @see #SEG_CLOSE
135      */
136     public int currentSegment(double[] coords) {
137         if (isDone()) {
138             throw new NoSuchElementException("rect iterator out of bounds");
139         }
140         if (index == 5) {
141             return SEG_CLOSE;
142         }
143         coords[0] = x;
144         coords[1] = y;
145         if (index == 1 || index == 2) {
146             coords[0] += w;
147         }
148         if (index == 2 || index == 3) {
149             coords[1] += h;
150         }
151         if (affine != null) {
152             affine.transform(coords, 0, coords, 0, 1);
153         }
154         return (index == 0 ? SEG_MOVETO : SEG_LINETO);
155     }
156 }