1 /*
2 * Copyright (c) 2016, 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.util.regex;
27
28 final class Grapheme {
29
30 /**
31 * Determines if there is an extended grapheme cluster boundary between two
32 * continuing characters {@code cp1} and {@code cp2}.
33 * <p>
34 * See Unicode Standard Annex #29 Unicode Text Segmentation for the specification
35 * for the extended grapheme cluster boundary rules
36 */
37 static boolean isBoundary(int cp1, int cp2) {
38 return rules[getType(cp1)][getType(cp2)];
39 }
40
41 // types
42 private static final int OTHER = 0;
43 private static final int CR = 1;
44 private static final int LF = 2;
45 private static final int CONTROL = 3;
46 private static final int EXTEND = 4;
47 private static final int RI = 5;
48 private static final int PREPEND = 6;
49 private static final int SPACINGMARK = 7;
50 private static final int L = 8;
51 private static final int V = 9;
52 private static final int T = 10;
53 private static final int LV = 11;
54 private static final int LVT = 12;
55
56 private static final int FIRST_TYPE = 0;
57 private static final int LAST_TYPE = 12;
58
59 private static boolean[][] rules;
60 static {
61 rules = new boolean[LAST_TYPE + 1][LAST_TYPE + 1];
62 // default, any + any
63 for (int i = FIRST_TYPE; i <= LAST_TYPE; i++)
64 for (int j = FIRST_TYPE; j <= LAST_TYPE; j++)
65 rules[i][j] = true;
66 // GB 6 L x (L | V | LV | VT)
67 rules[L][L] = false;
68 rules[L][V] = false;
69 rules[L][LV] = false;
70 rules[L][LVT] = false;
71 // GB 7 (LV | V) x (V | T)
72 rules[LV][V] = false;
73 rules[LV][T] = false;
74 rules[V][V] = false;
75 rules[V][T] = false;
76 // GB 8 (LVT | T) x T
77 rules[LVT][T] = false;
78 rules[T][T] = false;
79 // GB 8a RI x RI
80 rules[RI][RI] = false;
81 // GB 9 x Extend
82 // GB 9a x Spacing Mark
83 // GB 9b Prepend x
84 for (int i = FIRST_TYPE; i <= LAST_TYPE; i++) {
85 rules[i][EXTEND] = false;
86 rules[i][SPACINGMARK] = false;
87 rules[PREPEND][i] = false;
88 }
89 // GB 4 (Control | CR | LF) +
90 // GB 5 + (Control | CR | LF)
91 for (int i = FIRST_TYPE; i <= LAST_TYPE; i++)
92 for (int j = CR; j <= CONTROL; j++) {
93 rules[i][j] = true;
94 rules[j][i] = true;
95 }
96 // GB 3 CR x LF
97 rules[CR][LF] = false;
98 // GB 10 Any + Any -> default
99 }
100
101 // Hangul syllables
102 private static final int SYLLABLE_BASE = 0xAC00;
103 private static final int LCOUNT = 19;
104 private static final int VCOUNT = 21;
105 private static final int TCOUNT = 28;
106 private static final int NCOUNT = VCOUNT * TCOUNT; // 588
107 private static final int SCOUNT = LCOUNT * NCOUNT; // 11172
108
109 // #tr29: SpacingMark exceptions: The following (which have
110 // General_Category = Spacing_Mark and would otherwise be included)
111 // are specifically excluded
112 private static boolean isExcludedSpacingMark(int cp) {
113 return cp == 0x102B || cp == 0x102C || cp == 0x1038 ||
114 cp >= 0x1062 && cp <= 0x1064 ||
115 cp >= 0x1062 && cp <= 0x106D ||
116 cp == 0x1083 ||
117 cp >= 0x1087 && cp <= 0x108C ||
118 cp == 0x108F ||
119 cp >= 0x109A && cp <= 0x109C ||
120 cp == 0x1A61 || cp == 0x1A63 || cp == 0x1A64 ||
121 cp == 0xAA7B || cp == 0xAA7D;
122 }
123
124 @SuppressWarnings("fallthrough")
125 private static int getType(int cp) {
126 int type = Character.getType(cp);
127 switch(type) {
128 case Character.CONTROL:
129 if (cp == 0x000D)
130 return CR;
131 if (cp == 0x000A)
132 return LF;
133 return CONTROL;
134 case Character.UNASSIGNED:
135 // NOTE: #tr29 lists "Unassigned and Default_Ignorable_Code_Point" as Control
136 // but GraphemeBreakTest.txt lists u+0378/reserved-0378 as "Other"
137 // so type it as "Other" to make the test happy
138 if (cp == 0x0378)
139 return OTHER;
140
141 case Character.LINE_SEPARATOR:
142 case Character.PARAGRAPH_SEPARATOR:
143 case Character.SURROGATE:
144 return CONTROL;
145 case Character.FORMAT:
146 if (cp == 0x200C || cp == 0x200D)
147 return EXTEND;
148 return CONTROL;
149 case Character.NON_SPACING_MARK:
150 case Character.ENCLOSING_MARK:
151 // NOTE:
152 // #tr29 "plus a few General_Category = Spacing_Mark needed for
153 // canonical equivalence."
154 // but for "extended grapheme clusters" support, there is no
155 // need actually to diff "extend" and "spackmark" given GB9, GB9a
156 return EXTEND;
157 case Character.COMBINING_SPACING_MARK:
158 if (isExcludedSpacingMark(cp))
159 return OTHER;
160 // NOTE:
161 // 0x11720 and 0x11721 are mentioned in #tr29 as
162 // OTHER_LETTER but it appears their category has been updated to
163 // COMBING_SPACING_MARK already (verified in ver.8)
164 return SPACINGMARK;
165 case Character.OTHER_SYMBOL:
166 if (cp >= 0x1F1E6 && cp <= 0x1F1FF)
167 return RI;
168 return OTHER;
169 case Character.MODIFIER_LETTER:
170 // WARNING:
171 // not mentioned in #tr29 but listed in GraphemeBreakProperty.txt
172 if (cp == 0xFF9E || cp == 0xFF9F)
173 return EXTEND;
174 return OTHER;
175 case Character.OTHER_LETTER:
176 if (cp == 0x0E33 || cp == 0x0EB3)
177 return SPACINGMARK;
178 // hangul jamo
179 if (cp >= 0x1100 && cp <= 0x11FF) {
180 if (cp <= 0x115F)
181 return L;
182 if (cp <= 0x11A7)
183 return V;
184 return T;
185 }
186 // hangul syllables
187 int sindex = cp - SYLLABLE_BASE;
188 if (sindex >= 0 && sindex < SCOUNT) {
189
190 if (sindex % TCOUNT == 0)
191 return LV;
192 return LVT;
193 }
194 // hangul jamo_extended A
195 if (cp >= 0xA960 && cp <= 0xA97C)
196 return L;
197 // hangul jamo_extended B
198 if (cp >= 0xD7B0 && cp <= 0xD7C6)
199 return V;
200 if (cp >= 0xD7CB && cp <= 0xD7FB)
201 return T;
202 }
203 return OTHER;
204 }
205 }