1 /*
2 * Copyright (c) 2005, 2020, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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7 * published by the Free Software Foundation. Oracle designates this
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9 * by Oracle in the LICENSE file that accompanied this code.
10 *
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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 *
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25
26 /*
27 *******************************************************************************
28 * (C) Copyright IBM Corp. 1996-2005 - All Rights Reserved *
29 * *
30 * The original version of this source code and documentation is copyrighted *
31 * and owned by IBM, These materials are provided under terms of a License *
32 * Agreement between IBM and Sun. This technology is protected by multiple *
33 * US and International patents. This notice and attribution to IBM may not *
34 * to removed. *
35 *******************************************************************************
36 */
37
38 package jdk.internal.icu.text;
39
40 /**
41 * <code>Replaceable</code> is an interface representing a
42 * string of characters that supports the replacement of a range of
43 * itself with a new string of characters. It is used by APIs that
44 * change a piece of text while retaining metadata. Metadata is data
45 * other than the Unicode characters returned by char32At(). One
46 * example of metadata is style attributes; another is an edit
47 * history, marking each character with an author and revision number.
48 *
49 * <p>An implicit aspect of the <code>Replaceable</code> API is that
50 * during a replace operation, new characters take on the metadata of
51 * the old characters. For example, if the string "the <b>bold</b>
52 * font" has range (4, 8) replaced with "strong", then it becomes "the
53 * <b>strong</b> font".
54 *
55 * <p><code>Replaceable</code> specifies ranges using a start
56 * offset and a limit offset. The range of characters thus specified
57 * includes the characters at offset start..limit-1. That is, the
58 * start offset is inclusive, and the limit offset is exclusive.
59 *
60 * <p><code>Replaceable</code> also includes API to access characters
61 * in the string: <code>length()</code>, <code>charAt()</code>,
62 * <code>char32At()</code>, and <code>extractBetween()</code>.
63 *
64 * <p>For a subclass to support metadata, typical behavior of
65 * <code>replace()</code> is the following:
66 * <ul>
67 * <li>Set the metadata of the new text to the metadata of the first
68 * character replaced</li>
69 * <li>If no characters are replaced, use the metadata of the
70 * previous character</li>
71 * <li>If there is no previous character (i.e. start == 0), use the
72 * following character</li>
73 * <li>If there is no following character (i.e. the replaceable was
74 * empty), use default metadata</li>
75 * <li>If the code point U+FFFF is seen, it should be interpreted as
76 * a special marker having no metadata</li>
77 * </ul>
78 * If this is not the behavior, the subclass should document any differences.
79 *
80 * <p>Copyright © IBM Corporation 1999. All rights reserved.
81 *
82 * @author Alan Liu
83 * @stable ICU 2.0
84 */
85 public interface Replaceable {
86 /**
87 * Returns the number of 16-bit code units in the text.
88 * @return number of 16-bit code units in text
89 * @stable ICU 2.0
90 */
91 int length();
92
93 /**
94 * Returns the 16-bit code unit at the given offset into the text.
95 * @param offset an integer between 0 and <code>length()</code>-1
96 * inclusive
97 * @return 16-bit code unit of text at given offset
98 * @stable ICU 2.0
99 */
100 char charAt(int offset);
101
102 /**
103 * Copies characters from this object into the destination
104 * character array. The first character to be copied is at index
105 * <code>srcStart</code>; the last character to be copied is at
106 * index <code>srcLimit-1</code> (thus the total number of
107 * characters to be copied is <code>srcLimit-srcStart</code>). The
108 * characters are copied into the subarray of <code>dst</code>
109 * starting at index <code>dstStart</code> and ending at index
110 * <code>dstStart + (srcLimit-srcStart) - 1</code>.
111 *
112 * @param srcStart the beginning index to copy, inclusive;
113 * {@code 0 <= start <= limit}.
114 * @param srcLimit the ending index to copy, exclusive;
115 * {@code start <= limit <= length()}.
116 * @param dst the destination array.
117 * @param dstStart the start offset in the destination array.
118 * @stable ICU 2.0
119 */
120 void getChars(int srcStart, int srcLimit, char dst[], int dstStart);
121 }