[766] | 1 | /* |
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| 2 | Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. |
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| 3 | |
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| 4 | |
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| 5 | The MySQL Connector/J is licensed under the terms of the GPLv2 |
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| 6 | <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most MySQL Connectors. |
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| 7 | There are special exceptions to the terms and conditions of the GPLv2 as it is applied to |
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| 8 | this software, see the FLOSS License Exception |
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| 9 | <http://www.mysql.com/about/legal/licensing/foss-exception.html>. |
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| 10 | |
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| 11 | This program is free software; you can redistribute it and/or modify it under the terms |
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| 12 | of the GNU General Public License as published by the Free Software Foundation; version 2 |
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| 13 | of the License. |
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| 14 | |
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| 15 | This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; |
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| 16 | without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. |
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| 17 | See the GNU General Public License for more details. |
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| 18 | |
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| 19 | You should have received a copy of the GNU General Public License along with this |
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| 20 | program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth |
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| 21 | Floor, Boston, MA 02110-1301 USA |
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| 22 | |
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| 23 | |
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| 24 | |
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| 25 | */ |
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| 26 | package com.mysql.jdbc; |
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| 27 | |
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| 28 | /** |
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| 29 | * EscapeTokenizer breaks up an SQL statement into SQL and escape code parts. |
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| 30 | * |
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| 31 | * @author Mark Matthews |
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| 32 | */ |
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| 33 | public class EscapeTokenizer { |
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| 34 | // ~ Instance fields |
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| 35 | // -------------------------------------------------------- |
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| 36 | |
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| 37 | private int bracesLevel = 0; |
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| 38 | |
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| 39 | private boolean emittingEscapeCode = false; |
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| 40 | |
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| 41 | private boolean inComment = false; |
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| 42 | |
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| 43 | private boolean inQuotes = false; |
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| 44 | |
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| 45 | private char lastChar = 0; |
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| 46 | |
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| 47 | private char lastLastChar = 0; |
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| 48 | |
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| 49 | private int pos = 0; |
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| 50 | |
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| 51 | private char quoteChar = 0; |
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| 52 | |
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| 53 | private boolean sawVariableUse = false; |
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| 54 | |
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| 55 | private String source = null; |
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| 56 | |
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| 57 | private int sourceLength = 0; |
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| 58 | |
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| 59 | // ~ Constructors |
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| 60 | // ----------------------------------------------------------- |
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| 61 | |
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| 62 | /** |
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| 63 | * Creates a new EscapeTokenizer object. |
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| 64 | * |
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| 65 | * @param s |
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| 66 | * the string to tokenize |
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| 67 | */ |
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| 68 | public EscapeTokenizer(String s) { |
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| 69 | this.source = s; |
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| 70 | this.sourceLength = s.length(); |
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| 71 | this.pos = 0; |
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| 72 | } |
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| 73 | |
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| 74 | // ~ Methods |
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| 75 | // ---------------------------------------------------------------- |
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| 76 | |
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| 77 | /** |
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| 78 | * Does this tokenizer have more tokens available? |
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| 79 | * |
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| 80 | * @return if this tokenizer has more tokens available |
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| 81 | */ |
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| 82 | public synchronized boolean hasMoreTokens() { |
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| 83 | return (this.pos < this.sourceLength); |
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| 84 | } |
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| 85 | |
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| 86 | /** |
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| 87 | * Returns the next token |
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| 88 | * |
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| 89 | * @return the next token. |
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| 90 | */ |
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| 91 | public synchronized String nextToken() { |
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| 92 | StringBuffer tokenBuf = new StringBuffer(); |
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| 93 | |
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| 94 | if (this.emittingEscapeCode) { |
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| 95 | tokenBuf.append("{"); //$NON-NLS-1$ |
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| 96 | this.emittingEscapeCode = false; |
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| 97 | } |
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| 98 | |
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| 99 | for (; this.pos < this.sourceLength; this.pos++) { |
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| 100 | char c = this.source.charAt(this.pos); |
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| 101 | |
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| 102 | // Detect variable usage |
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| 103 | |
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| 104 | if (!this.inQuotes && c == '@') { |
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| 105 | this.sawVariableUse = true; |
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| 106 | } |
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| 107 | |
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| 108 | if ((c == '\'' || c == '"') && !inComment) { |
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| 109 | if (this.inQuotes && c == quoteChar) { |
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| 110 | if (this.pos + 1 < this.sourceLength) { |
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| 111 | if (this.source.charAt(this.pos + 1) == quoteChar) { |
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| 112 | // Doubled-up quote escape, if the first quote isn't already escaped |
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| 113 | if (this.lastChar != '\\') { |
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| 114 | tokenBuf.append(quoteChar); |
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| 115 | tokenBuf.append(quoteChar); |
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| 116 | this.pos++; |
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| 117 | continue; |
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| 118 | } |
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| 119 | } |
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| 120 | } |
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| 121 | } |
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| 122 | if (this.lastChar != '\\') { |
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| 123 | if (this.inQuotes) { |
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| 124 | if (this.quoteChar == c) { |
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| 125 | this.inQuotes = false; |
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| 126 | } |
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| 127 | } else { |
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| 128 | this.inQuotes = true; |
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| 129 | this.quoteChar = c; |
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| 130 | } |
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| 131 | } else if (this.lastLastChar == '\\') { |
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| 132 | if (this.inQuotes) { |
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| 133 | if (this.quoteChar == c) { |
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| 134 | this.inQuotes = false; |
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| 135 | } |
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| 136 | } else { |
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| 137 | this.inQuotes = true; |
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| 138 | this.quoteChar = c; |
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| 139 | } |
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| 140 | } |
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| 141 | |
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| 142 | tokenBuf.append(c); |
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| 143 | } else if (c == '-') { |
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| 144 | if ((this.lastChar == '-') |
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| 145 | && ((this.lastLastChar != '\\') && !this.inQuotes)) { |
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| 146 | this.inComment = true; |
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| 147 | } |
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| 148 | |
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| 149 | tokenBuf.append(c); |
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| 150 | } else if ((c == '\n') || (c == '\r')) { |
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| 151 | this.inComment = false; |
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| 152 | |
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| 153 | tokenBuf.append(c); |
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| 154 | } else if (c == '{') { |
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| 155 | if (this.inQuotes || this.inComment) { |
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| 156 | tokenBuf.append(c); |
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| 157 | } else { |
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| 158 | this.bracesLevel++; |
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| 159 | |
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| 160 | if (this.bracesLevel == 1) { |
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| 161 | this.pos++; |
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| 162 | this.emittingEscapeCode = true; |
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| 163 | |
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| 164 | return tokenBuf.toString(); |
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| 165 | } |
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| 166 | |
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| 167 | tokenBuf.append(c); |
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| 168 | } |
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| 169 | } else if (c == '}') { |
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| 170 | tokenBuf.append(c); |
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| 171 | |
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| 172 | if (!this.inQuotes && !this.inComment) { |
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| 173 | this.lastChar = c; |
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| 174 | |
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| 175 | this.bracesLevel--; |
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| 176 | |
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| 177 | if (this.bracesLevel == 0) { |
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| 178 | this.pos++; |
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| 179 | |
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| 180 | return tokenBuf.toString(); |
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| 181 | } |
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| 182 | } |
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| 183 | } else { |
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| 184 | tokenBuf.append(c); |
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| 185 | } |
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| 186 | |
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| 187 | this.lastLastChar = this.lastChar; |
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| 188 | this.lastChar = c; |
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| 189 | } |
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| 190 | |
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| 191 | return tokenBuf.toString(); |
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| 192 | } |
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| 193 | |
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| 194 | boolean sawVariableUse() { |
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| 195 | return this.sawVariableUse; |
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| 196 | } |
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| 197 | } |
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