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Java > Open Source Codes > org > jruby > lexer > yacc > Keyword


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2  * Version: CPL 1.0/GPL 2.0/LGPL 2.1
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5  * License Version 1.0 (the "License"); you may not use this file
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14  * Copyright (C) 2002-2004 Jan Arne Petersen <jpetersen@uni-bonn.de>
15  * Copyright (C) 2004 Anders Bengtsson <ndrsbngtssn@yahoo.se>
16  * Copyright (C) 2004 Thomas E Enebo <enebo@acm.org>
17  * Copyright (C) 2004 Stefan Matthias Aust <sma@3plus4.de>
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31 package org.jruby.lexer.yacc;
32
33 import org.jruby.parser.Tokens;
34
35 public class Keyword implements Tokens {
36     public String JavaDoc name;
37     public int id0, id1;
38     public LexState state;
39
40     private Keyword() {
41         this("", 0, 0, LexState.EXPR_BEG);
42     }
43
44     private Keyword(String JavaDoc name, int id0, int id1, LexState state) {
45         this.name = name;
46         this.id0 = id0;
47         this.id1 = id1;
48         this.state = state;
49     }
50
51 // private static final int TOTAL_KEYWORDS = 40;
52 private static final int MIN_WORD_LENGTH = 2;
53     private static final int MAX_WORD_LENGTH = 8;
54     private static final int MIN_HASH_VALUE = 6;
55     private static final int MAX_HASH_VALUE = 55;
56
57     private static final byte[] asso_values = {
58         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
59         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
60         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
61         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
62         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
63         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
64         56, 56, 56, 11, 56, 56, 36, 56, 1, 37,
65         31, 1, 56, 56, 56, 56, 29, 56, 1, 56,
66         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
67         56, 56, 56, 56, 56, 1, 56, 32, 1, 2,
68         1, 1, 4, 23, 56, 17, 56, 20, 9, 2,
69         9, 26, 14, 56, 5, 1, 1, 16, 56, 21,
70         20, 9, 56, 56, 56, 56, 56, 56, 56, 56,
71         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
72         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
73         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
74         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
75         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
76         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
77         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
78         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
79         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
80         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
81         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
82         56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
83         56, 56, 56, 56, 56, 56
84     };
85
86     private static int hash(String JavaDoc str, int len) {
87         int hval = len;
88         switch (hval) {
89         default:
90         case 3:
91             hval += asso_values[str.charAt(2) & 255];
92         case 2:
93         case 1:
94             hval += asso_values[str.charAt(0) & 255];
95             break;
96         }
97         return hval + asso_values[str.charAt(len - 1) & 255];
98     }
99
100     private static final Keyword[] wordlist = {
101         new Keyword(),
102         new Keyword(),
103         new Keyword(),
104         new Keyword(),
105         new Keyword(),
106         new Keyword(),
107         new Keyword("end", kEND, kEND, LexState.EXPR_END),
108         new Keyword("else", kELSE, kELSE, LexState.EXPR_BEG),
109         new Keyword("case", kCASE, kCASE, LexState.EXPR_BEG),
110         new Keyword("ensure", kENSURE, kENSURE, LexState.EXPR_BEG),
111         new Keyword("module", kMODULE, kMODULE, LexState.EXPR_BEG),
112         new Keyword("elsif", kELSIF, kELSIF, LexState.EXPR_BEG),
113         new Keyword("def", kDEF, kDEF, LexState.EXPR_FNAME),
114         new Keyword("rescue", kRESCUE, kRESCUE_MOD, LexState.EXPR_MID),
115         new Keyword("not", kNOT, kNOT, LexState.EXPR_BEG),
116         new Keyword("then", kTHEN, kTHEN, LexState.EXPR_BEG),
117         new Keyword("yield", kYIELD, kYIELD, LexState.EXPR_ARG),
118         new Keyword("for", kFOR, kFOR, LexState.EXPR_BEG),
119         new Keyword("self", kSELF, kSELF, LexState.EXPR_END),
120         new Keyword("false", kFALSE, kFALSE, LexState.EXPR_END),
121         new Keyword("retry", kRETRY, kRETRY, LexState.EXPR_END),
122         new Keyword("return", kRETURN, kRETURN, LexState.EXPR_MID),
123         new Keyword("true", kTRUE, kTRUE, LexState.EXPR_END),
124         new Keyword("if", kIF, kIF_MOD, LexState.EXPR_BEG),
125         new Keyword("defined?", kDEFINED, kDEFINED, LexState.EXPR_ARG),
126         new Keyword("super", kSUPER, kSUPER, LexState.EXPR_ARG),
127         new Keyword("undef", kUNDEF, kUNDEF, LexState.EXPR_FNAME),
128         new Keyword("break", kBREAK, kBREAK, LexState.EXPR_MID),
129         new Keyword("in", kIN, kIN, LexState.EXPR_BEG),
130         new Keyword("do", kDO, kDO, LexState.EXPR_BEG),
131         new Keyword("nil", kNIL, kNIL, LexState.EXPR_END),
132         new Keyword("until", kUNTIL, kUNTIL_MOD, LexState.EXPR_BEG),
133         new Keyword("unless", kUNLESS, kUNLESS_MOD, LexState.EXPR_BEG),
134         new Keyword("or", kOR, kOR, LexState.EXPR_BEG),
135         new Keyword("next", kNEXT, kNEXT, LexState.EXPR_MID),
136         new Keyword("when", kWHEN, kWHEN, LexState.EXPR_BEG),
137         new Keyword("redo", kREDO, kREDO, LexState.EXPR_END),
138         new Keyword("and", kAND, kAND, LexState.EXPR_BEG),
139         new Keyword("begin", kBEGIN, kBEGIN, LexState.EXPR_BEG),
140         new Keyword("__LINE__", k__LINE__, k__LINE__, LexState.EXPR_END),
141         new Keyword("class", kCLASS, kCLASS, LexState.EXPR_CLASS),
142         new Keyword("__FILE__", k__FILE__, k__FILE__, LexState.EXPR_END),
143         new Keyword("END", klEND, klEND, LexState.EXPR_END),
144         new Keyword("BEGIN", klBEGIN, klBEGIN, LexState.EXPR_END),
145         new Keyword("while", kWHILE, kWHILE_MOD, LexState.EXPR_BEG),
146         new Keyword(),
147         new Keyword(),
148         new Keyword(),
149         new Keyword(),
150         new Keyword(),
151         new Keyword(),
152         new Keyword(),
153         new Keyword(),
154         new Keyword(),
155         new Keyword(),
156         new Keyword("alias", kALIAS, kALIAS, LexState.EXPR_FNAME)
157     };
158
159     public static Keyword getKeyword(String JavaDoc str, int len) {
160         if (len <= MAX_WORD_LENGTH && len >= MIN_WORD_LENGTH) {
161             int key = hash(str, len);
162             if (key <= MAX_HASH_VALUE && key >= MIN_HASH_VALUE) {
163                 if (str.equals(wordlist[key].name)) {
164                     return wordlist[key];
165                 }
166             }
167         }
168         return null;
169     }
170 }
171
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