1 // © 2016 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html#License 3 /* 4 ******************************************************************************* 5 * Copyright (C) 2011, International Business Machines 6 * Corporation and others. All Rights Reserved. 7 ******************************************************************************* 8 * created on: 2011feb25 9 * created by: Markus W. Scherer 10 */ 11 12 package com.ibm.icu.impl; 13 14 /** 15 * Implements the immutable Unicode properties Pattern_Syntax and Pattern_White_Space. 16 * Hardcodes these properties, does not load data, does not depend on other ICU classes. 17 * <p> 18 * Note: Both properties include ASCII as well as non-ASCII, non-Latin-1 code points, 19 * and both properties only include BMP code points (no supplementary ones). 20 * Pattern_Syntax includes some unassigned code points. 21 * <p> 22 * [:Pattern_White_Space:] = 23 * [\u0009-\u000D\ \u0085\u200E\u200F\u2028\u2029] 24 * <p> 25 * [:Pattern_Syntax:] = 26 * [!-/\:-@\[-\^`\{-~\u00A1-\u00A7\u00A9\u00AB\u00AC\u00AE 27 * \u00B0\u00B1\u00B6\u00BB\u00BF\u00D7\u00F7 28 * \u2010-\u2027\u2030-\u203E\u2041-\u2053\u2055-\u205E 29 * \u2190-\u245F\u2500-\u2775\u2794-\u2BFF\u2E00-\u2E7F 30 * \u3001-\u3003\u3008-\u3020\u3030\uFD3E\uFD3F\uFE45\uFE46] 31 * @author mscherer 32 */ 33 public final class PatternProps { 34 /** 35 * @return true if c is a Pattern_Syntax code point. 36 */ isSyntax(int c)37 public static boolean isSyntax(int c) { 38 if(c<0) { 39 return false; 40 } else if(c<=0xff) { 41 return latin1[c]==3; 42 } else if(c<0x2010) { 43 return false; 44 } else if(c<=0x3030) { 45 int bits=syntax2000[index2000[(c-0x2000)>>5]]; 46 return ((bits>>(c&0x1f))&1)!=0; 47 } else if(0xfd3e<=c && c<=0xfe46) { 48 return c<=0xfd3f || 0xfe45<=c; 49 } else { 50 return false; 51 } 52 } 53 54 /** 55 * @return true if c is a Pattern_Syntax or Pattern_White_Space code point. 56 */ isSyntaxOrWhiteSpace(int c)57 public static boolean isSyntaxOrWhiteSpace(int c) { 58 if(c<0) { 59 return false; 60 } else if(c<=0xff) { 61 return latin1[c]!=0; 62 } else if(c<0x200e) { 63 return false; 64 } else if(c<=0x3030) { 65 int bits=syntaxOrWhiteSpace2000[index2000[(c-0x2000)>>5]]; 66 return ((bits>>(c&0x1f))&1)!=0; 67 } else if(0xfd3e<=c && c<=0xfe46) { 68 return c<=0xfd3f || 0xfe45<=c; 69 } else { 70 return false; 71 } 72 } 73 74 /** 75 * @return true if c is a Pattern_White_Space character. 76 */ isWhiteSpace(int c)77 public static boolean isWhiteSpace(int c) { 78 if(c<0) { 79 return false; 80 } else if(c<=0xff) { 81 return latin1[c]==5; 82 } else if(0x200e<=c && c<=0x2029) { 83 return c<=0x200f || 0x2028<=c; 84 } else { 85 return false; 86 } 87 } 88 89 /** 90 * Skips over Pattern_White_Space starting at index i of the CharSequence. 91 * @return The smallest index at or after i with a non-white space character. 92 */ skipWhiteSpace(CharSequence s, int i)93 public static int skipWhiteSpace(CharSequence s, int i) { 94 while(i<s.length() && isWhiteSpace(s.charAt(i))) { 95 ++i; 96 } 97 return i; 98 } 99 100 /** 101 * @return s except with leading and trailing Pattern_White_Space removed. 102 */ trimWhiteSpace(String s)103 public static String trimWhiteSpace(String s) { 104 if(s.length()==0 || (!isWhiteSpace(s.charAt(0)) && !isWhiteSpace(s.charAt(s.length()-1)))) { 105 return s; 106 } 107 int start=0; 108 int limit=s.length(); 109 while(start<limit && isWhiteSpace(s.charAt(start))) { 110 ++start; 111 } 112 if(start<limit) { 113 // There is non-white space at start; we will not move limit below that, 114 // so we need not test start<limit in the loop. 115 while(isWhiteSpace(s.charAt(limit-1))) { 116 --limit; 117 } 118 } 119 return s.substring(start, limit); 120 } 121 122 /** 123 * Tests whether the CharSequence contains a "pattern identifier", that is, 124 * whether it contains only non-Pattern_White_Space, non-Pattern_Syntax characters. 125 * @return true if there are no Pattern_White_Space or Pattern_Syntax characters in s. 126 */ isIdentifier(CharSequence s)127 public static boolean isIdentifier(CharSequence s) { 128 int limit=s.length(); 129 if(limit==0) { 130 return false; 131 } 132 int start=0; 133 do { 134 if(isSyntaxOrWhiteSpace(s.charAt(start++))) { 135 return false; 136 } 137 } while(start<limit); 138 return true; 139 } 140 141 /** 142 * Tests whether the CharSequence contains a "pattern identifier", that is, 143 * whether it contains only non-Pattern_White_Space, non-Pattern_Syntax characters. 144 * @return true if there are no Pattern_White_Space or Pattern_Syntax characters 145 * in s between start and (exclusive) limit. 146 */ isIdentifier(CharSequence s, int start, int limit)147 public static boolean isIdentifier(CharSequence s, int start, int limit) { 148 if(start>=limit) { 149 return false; 150 } 151 do { 152 if(isSyntaxOrWhiteSpace(s.charAt(start++))) { 153 return false; 154 } 155 } while(start<limit); 156 return true; 157 } 158 159 /** 160 * Skips over a "pattern identifier" starting at index i of the CharSequence. 161 * @return The smallest index at or after i with 162 * a Pattern_White_Space or Pattern_Syntax character. 163 */ skipIdentifier(CharSequence s, int i)164 public static int skipIdentifier(CharSequence s, int i) { 165 while(i<s.length() && !isSyntaxOrWhiteSpace(s.charAt(i))) { 166 ++i; 167 } 168 return i; 169 } 170 171 /* 172 * One byte per Latin-1 character. 173 * Bit 0 is set if either Pattern property is true, 174 * bit 1 if Pattern_Syntax is true, 175 * bit 2 if Pattern_White_Space is true. 176 * That is, Pattern_Syntax is encoded as 3 and Pattern_White_Space as 5. 177 */ 178 private static final byte latin1[]=new byte[] { // 256 179 // WS: 9..D 180 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 5, 5, 5, 5, 0, 0, 181 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 182 // WS: 20 Syntax: 21..2F 183 5, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 184 // Syntax: 3A..40 185 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 3, 3, 3, 3, 186 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 187 // Syntax: 5B..5E 188 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 3, 3, 0, 189 // Syntax: 60 190 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 191 // Syntax: 7B..7E 192 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 3, 3, 0, 193 // WS: 85 194 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 195 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 196 // Syntax: A1..A7, A9, AB, AC, AE 197 0, 3, 3, 3, 3, 3, 3, 3, 0, 3, 0, 3, 3, 0, 3, 0, 198 // Syntax: B0, B1, B6, BB, BF 199 3, 3, 0, 0, 0, 0, 3, 0, 0, 0, 0, 3, 0, 0, 0, 3, 200 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 201 // Syntax: D7 202 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 203 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 204 // Syntax: F7 205 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0 206 }; 207 208 /* 209 * One byte per 32 characters from U+2000..U+303F indexing into 210 * a small table of 32-bit data words. 211 * The first two data words are all-zeros and all-ones. 212 */ 213 private static final byte index2000[]=new byte[] { // 130 214 2, 3, 4, 0, 0, 0, 0, 0, // 20xx 215 0, 0, 0, 0, 5, 1, 1, 1, // 21xx 216 1, 1, 1, 1, 1, 1, 1, 1, // 22xx 217 1, 1, 1, 1, 1, 1, 1, 1, // 23xx 218 1, 1, 1, 0, 0, 0, 0, 0, // 24xx 219 1, 1, 1, 1, 1, 1, 1, 1, // 25xx 220 1, 1, 1, 1, 1, 1, 1, 1, // 26xx 221 1, 1, 1, 6, 7, 1, 1, 1, // 27xx 222 1, 1, 1, 1, 1, 1, 1, 1, // 28xx 223 1, 1, 1, 1, 1, 1, 1, 1, // 29xx 224 1, 1, 1, 1, 1, 1, 1, 1, // 2Axx 225 1, 1, 1, 1, 1, 1, 1, 1, // 2Bxx 226 0, 0, 0, 0, 0, 0, 0, 0, // 2Cxx 227 0, 0, 0, 0, 0, 0, 0, 0, // 2Dxx 228 1, 1, 1, 1, 0, 0, 0, 0, // 2Exx 229 0, 0, 0, 0, 0, 0, 0, 0, // 2Fxx 230 8, 9 // 3000..303F 231 }; 232 233 /* 234 * One 32-bit integer per 32 characters. Ranges of all-false and all-true 235 * are mapped to the first two values, other ranges map to appropriate bit patterns. 236 */ 237 private static final int syntax2000[]=new int[] { 238 0, 239 -1, 240 0xffff0000, // 2: 2010..201F 241 0x7fff00ff, // 3: 2020..2027, 2030..203E 242 0x7feffffe, // 4: 2041..2053, 2055..205E 243 0xffff0000, // 5: 2190..219F 244 0x003fffff, // 6: 2760..2775 245 0xfff00000, // 7: 2794..279F 246 0xffffff0e, // 8: 3001..3003, 3008..301F 247 0x00010001 // 9: 3020, 3030 248 }; 249 250 /* 251 * Same as syntax2000, but with additional bits set for the 252 * Pattern_White_Space characters 200E 200F 2028 2029. 253 */ 254 private static final int syntaxOrWhiteSpace2000[]=new int[] { 255 0, 256 -1, 257 0xffffc000, // 2: 200E..201F 258 0x7fff03ff, // 3: 2020..2029, 2030..203E 259 0x7feffffe, // 4: 2041..2053, 2055..205E 260 0xffff0000, // 5: 2190..219F 261 0x003fffff, // 6: 2760..2775 262 0xfff00000, // 7: 2794..279F 263 0xffffff0e, // 8: 3001..3003, 3008..301F 264 0x00010001 // 9: 3020, 3030 265 }; 266 } 267