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1
10
11 package com.triactive.jdo.store;
12
13 import com.triactive.jdo.util.Imports;
14 import java.math.BigDecimal  ;
15 import java.math.BigInteger ;
16 import java.text.CharacterIterator ;
17 import java.text.StringCharacterIterator ;
18 import javax.jdo.JDOUserException;
19
20
21 class Parser
22 {
23 private final String input;
24 private final Imports imports;
25 private final CharacterIterator ci;
26
27
28 public Parser(String input, Imports imports)
29 {
30 this.input = input;
31 this.imports = imports;
32
33 ci = new StringCharacterIterator (input);
34 }
35
36
37 public String getInput()
38 {
39 return input;
40 }
41
42
43 public int getIndex()
44 {
45 return ci.getIndex();
46 }
47
48
49 public int skipWS()
50 {
51 int startIdx = ci.getIndex();
52 char c = ci.current();
53
54 while (Character.isWhitespace(c))
55 c = ci.next();
56
57 return startIdx;
58 }
59
60
61 public boolean parseEOS()
62 {
63 skipWS();
64
65 return ci.current() == CharacterIterator.DONE;
66 }
67
68
69 public boolean parseChar(char c)
70 {
71 skipWS();
72
73 if (ci.current() == c)
74 {
75 ci.next();
76 return true;
77 }
78 else
79 return false;
80 }
81
82
83 public boolean parseChar(char c, char unlessFollowedBy)
84 {
85 int savedIdx = skipWS();
86
87 if (ci.current() == c && ci.next() != unlessFollowedBy)
88 return true;
89 else
90 {
91 ci.setIndex(savedIdx);
92 return false;
93 }
94 }
95
96
97 public boolean parseString(String s)
98 {
99 int savedIdx = skipWS();
100
101 int len = s.length();
102 char c = ci.current();
103
104 for (int i = 0; i < len; ++i)
105 {
106 if (c != s.charAt(i))
107 {
108 ci.setIndex(savedIdx);
109 return false;
110 }
111
112 c = ci.next();
113 }
114
115 return true;
116 }
117
118
119 public boolean parseString(String s, char unlessFollowedBy)
120 {
121 int savedIdx = skipWS();
122
123 if (parseString(s) && ci.next() != unlessFollowedBy)
124 return true;
125 else
126 {
127 ci.setIndex(savedIdx);
128 return false;
129 }
130 }
131
132
133 public String parseIdentifier()
134 {
135 skipWS();
136 char c = ci.current();
137
138 if (!Character.isJavaIdentifierStart(c))
139 return null;
140
141 StringBuffer id = new StringBuffer ().append(c);
142
143 while (Character.isJavaIdentifierPart(c = ci.next()))
144 id.append(c);
145
146 return id.toString();
147 }
148
149
150 public String parseName()
151 {
152 int savedIdx = skipWS();
153 String id;
154
155 if ((id = parseIdentifier()) == null)
156 return null;
157
158 StringBuffer qn = new StringBuffer (id);
159
160 while (parseChar('.'))
161 {
162 if ((id = parseIdentifier()) == null)
163 {
164 ci.setIndex(savedIdx);
165 return null;
166 }
167
168 qn.append('.').append(id);
169 }
170
171 return qn.toString();
172 }
173
174
175 public Class parseCast()
176 {
177 int savedIdx = skipWS();
178 String typeName;
179
180 if (!parseChar('(') || (typeName = parseName()) == null || !parseChar(')'))
181 {
182 ci.setIndex(savedIdx);
183 return null;
184 }
185
186 try
187 {
188 return imports.resolveClassDeclaration(typeName);
189 }
190 catch (ClassNotFoundException e)
191 {
192 ci.setIndex(savedIdx);
193 return null;
194 }
195 }
196
197
198 private final static boolean isDecDigit(char c)
199 {
200 return c >= '0' && c <= '9';
201 }
202
203
204 private final static boolean isOctDigit(char c)
205 {
206 return c >= '0' && c <= '7';
207 }
208
209
210 private final static boolean isHexDigit(char c)
211 {
212 return c >= '0' && c <= '9' || c >= 'a' && c <= 'f' || c >= 'A' && c <= 'F';
213 }
214
215
216 public BigInteger parseIntegerLiteral()
217 {
218 int savedIdx = skipWS();
219
220 StringBuffer digits = new StringBuffer ();
221 int radix;
222 char c = ci.current();
223
224 if (c == '0')
225 {
226 c = ci.next();
227
228 if (c == 'x' || c == 'X')
229 {
230 radix = 16;
231 c = ci.next();
232
233 while (isHexDigit(c))
234 {
235 digits.append(c);
236 c = ci.next();
237 }
238 }
239 else if (isOctDigit(c))
240 {
241 radix = 8;
242
243 do
244 {
245 digits.append(c);
246 c = ci.next();
247 } while (isOctDigit(c));
248 }
249 else
250 {
251 radix = 10;
252 digits.append('0');
253 }
254 }
255 else
256 {
257 radix = 10;
258
259 while (isDecDigit(c))
260 {
261 digits.append(c);
262 c = ci.next();
263 }
264 }
265
266 if (digits.length() == 0)
267 {
268 ci.setIndex(savedIdx);
269 return null;
270 }
271
272 if (c == 'l' || c == 'L')
273 ci.next();
274
275 return new BigInteger (digits.toString(), radix);
276 }
277
278
279 public BigDecimal parseFloatingPointLiteral()
280 {
281 int savedIdx = skipWS();
282 StringBuffer val = new StringBuffer ();
283 boolean dotSeen = false;
284 boolean expSeen = false;
285 boolean sfxSeen = false;
286
287 char c = ci.current();
288
289 while (isDecDigit(c))
290 {
291 val.append(c);
292 c = ci.next();
293 }
294
295 if (c == '.')
296 {
297 dotSeen = true;
298 val.append(c);
299 c = ci.next();
300
301 while (isDecDigit(c))
302 {
303 val.append(c);
304 c = ci.next();
305 }
306 }
307
308 if (val.length() < (dotSeen ? 2 : 1))
309 {
310 ci.setIndex(savedIdx);
311 return null;
312 }
313
314 if (c == 'e' || c == 'E')
315 {
316 expSeen = true;
317 val.append(c);
318 c = ci.next();
319
320 if (c != '+' && c != '-' && !isDecDigit(c))
321 {
322 ci.setIndex(savedIdx);
323 return null;
324 }
325
326 do
327 {
328 val.append(c);
329 c = ci.next();
330 } while (isDecDigit(c));
331 }
332
333 if (c == 'f' || c == 'F' || c == 'd' || c == 'D')
334 {
335 sfxSeen = true;
336 ci.next();
337 }
338
339 if (!dotSeen && !expSeen && !sfxSeen)
340 {
341 ci.setIndex(savedIdx);
342 return null;
343 }
344
345 return new BigDecimal (val.toString());
346 }
347
348
349 public Boolean parseBooleanLiteral()
350 {
351 int savedIdx = skipWS();
352 String id;
353
354 if ((id = parseIdentifier()) == null)
355 return null;
356
357 if (id.equals("true"))
358 return Boolean.TRUE;
359 else if (id.equals("false"))
360 return Boolean.FALSE;
361 else
362 {
363 ci.setIndex(savedIdx);
364 return null;
365 }
366 }
367
368
369 public Character parseCharacterLiteral()
370 {
371 skipWS();
372
373 if (ci.current() != '\'')
374 return null;
375
376 char c = ci.next();
377
378 if (c == CharacterIterator.DONE)
379 throw new JDOUserException("Invalid character literal: " + input);
380
381 if (c == '\\')
382 c = parseEscapedCharacter();
383
384 if (ci.next() != '\'')
385 throw new JDOUserException("Invalid character literal: " + input);
386
387 ci.next();
388
389 return new Character (c);
390 }
391
392
393 public String parseStringLiteral()
394 {
395 skipWS();
396
397 if (ci.current() != '"')
398 return null;
399
400 StringBuffer lit = new StringBuffer ();
401 char c;
402
403 while ((c = ci.next()) != '"')
404 {
405 if (c == CharacterIterator.DONE)
406 throw new JDOUserException("Invalid string literal: " + input);
407
408 if (c == '\\')
409 c = parseEscapedCharacter();
410
411 lit.append(c);
412 }
413
414 ci.next();
415
416 return lit.toString();
417 }
418
419
420 private char parseEscapedCharacter()
421 {
422 char c;
423
424 if (isOctDigit(c = ci.next()))
425 {
426 int i = (int)(c - '0');
427
428 if (isOctDigit(c = ci.next()))
429 {
430 i = i * 8 + (int)(c - '0');
431
432 if (isOctDigit(c = ci.next()))
433 i = i * 8 + (int)(c - '0');
434 else
435 ci.previous();
436 }
437 else
438 ci.previous();
439
440 if (i > 0xff)
441 throw new JDOUserException("Invalid character escape: '\\" + Integer.toOctalString(i) + "'");
442
443 return (char)i;
444 }
445 else
446 {
447 switch (c)
448 {
449 case 'b': return '\b';
450 case 't': return '\t';
451 case 'n': return '\n';
452 case 'f': return '\f';
453 case 'r': return '\r';
454 case '"': return '"';
455 case '\'': return '\'';
456 case '\\': return '\\';
457 default:
458 throw new JDOUserException("Invalid character escape: '\\" + c + "'");
459 }
460 }
461 }
462
463
464 public boolean parseNullLiteral()
465 {
466 int savedIdx = skipWS();
467 String id;
468
469 if ((id = parseIdentifier()) == null)
470 return false;
471 else if (id.equals("null"))
472 return true;
473 else
474 {
475 ci.setIndex(savedIdx);
476 return false;
477 }
478 }
479 }
480 |
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