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1   /*
2    * Copyright (c) 2000, 2012, 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  package java.text;
26  
27  import java.util.ArrayList;
28  
29  /**
30   * CharacterIteratorFieldDelegate combines the notifications from a Format
31   * into a resulting <code>AttributedCharacterIterator</code>. The resulting
32   * <code>AttributedCharacterIterator</code> can be retrieved by way of
33   * the <code>getIterator</code> method.
34   *
35   */
36  class CharacterIteratorFieldDelegate implements Format.FieldDelegate {
37      /**
38       * Array of AttributeStrings. Whenever <code>formatted</code> is invoked
39       * for a region > size, a new instance of AttributedString is added to
40       * attributedStrings. Subsequent invocations of <code>formatted</code>
41       * for existing regions result in invoking addAttribute on the existing
42       * AttributedStrings.
43       */
44      private ArrayList<AttributedString> attributedStrings;
45      /**
46       * Running count of the number of characters that have
47       * been encountered.
48       */
49      private int size;
50  
51  
52      CharacterIteratorFieldDelegate() {
53          attributedStrings = new ArrayList<>();
54      }
55  
56      public void formatted(Format.Field attr, Object value, int start, int end,
57                            StringBuffer buffer) {
58          if (start != end) {
59              if (start < size) {
60                  // Adjust attributes of existing runs
61                  int index = size;
62                  int asIndex = attributedStrings.size() - 1;
63  
64                  while (start < index) {
65                      AttributedString as = attributedStrings.
66                                             get(asIndex--);
67                      int newIndex = index - as.length();
68                      int aStart = Math.max(0, start - newIndex);
69  
70                      as.addAttribute(attr, value, aStart, Math.min(
71                                      end - start, as.length() - aStart) +
72                                      aStart);
73                      index = newIndex;
74                  }
75              }
76              if (size < start) {
77                  // Pad attributes
78                  attributedStrings.add(new AttributedString(
79                                            buffer.substring(size, start)));
80                  size = start;
81              }
82              if (size < end) {
83                  // Add new string
84                  int aStart = Math.max(start, size);
85                  AttributedString string = new AttributedString(
86                                     buffer.substring(aStart, end));
87  
88                  string.addAttribute(attr, value);
89                  attributedStrings.add(string);
90                  size = end;
91              }
92          }
93      }
94  
95      public void formatted(int fieldID, Format.Field attr, Object value,
96                            int start, int end, StringBuffer buffer) {
97          formatted(attr, value, start, end, buffer);
98      }
99  
100     /**
101      * Returns an <code>AttributedCharacterIterator</code> that can be used
102      * to iterate over the resulting formatted String.
103      *
104      * @pararm string Result of formatting.
105      */
106     public AttributedCharacterIterator getIterator(String string) {
107         // Add the last AttributedCharacterIterator if necessary
108         // assert(size <= string.length());
109         if (string.length() > size) {
110             attributedStrings.add(new AttributedString(
111                                   string.substring(size)));
112             size = string.length();
113         }
114         int iCount = attributedStrings.size();
115         AttributedCharacterIterator iterators[] = new
116                                     AttributedCharacterIterator[iCount];
117 
118         for (int counter = 0; counter < iCount; counter++) {
119             iterators[counter] = attributedStrings.
120                                   get(counter).getIterator();
121         }
122         return new AttributedString(iterators).getIterator();
123     }
124 }