1 | /***********************************************************************
|
---|
2 | * @(#)$RCSfile: Tokenizer.java,v $ $Revision: 1.6 $$Date: 2006/04/21 14:14:56 $
|
---|
3 | *
|
---|
4 | * Copyright (c) Christof Dallermassl
|
---|
5 | *
|
---|
6 | * This program is free software; you can redistribute it and/or modify
|
---|
7 | * it under the terms of the GNU Lesser General Public License (LGPL)
|
---|
8 | * as published by the Free Software Foundation; either version 2.1 of
|
---|
9 | * the License, or (at your option) any later version.
|
---|
10 | *
|
---|
11 | * This program is distributed in the hope that it will be useful,
|
---|
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
|
---|
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
---|
14 | * GNU Lesser General Public License for more details.
|
---|
15 | *
|
---|
16 | * You should have received a copy of the GNU Lesser General Public
|
---|
17 | * License along with this program; if not, write to the
|
---|
18 | * Free Software Foundation, Inc.,
|
---|
19 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
---|
20 | ***********************************************************************/
|
---|
21 |
|
---|
22 | package org.dinopolis.util.io;
|
---|
23 |
|
---|
24 | import java.io.IOException;
|
---|
25 | import java.io.PushbackReader;
|
---|
26 | import java.io.Reader;
|
---|
27 | import java.io.StringReader;
|
---|
28 | import java.util.ArrayList;
|
---|
29 | import java.util.Iterator;
|
---|
30 | import java.util.List;
|
---|
31 |
|
---|
32 | //----------------------------------------------------------------------
|
---|
33 | /**
|
---|
34 |
|
---|
35 | * This tokenizer merges the benefits of the java.lang.StringTokenizer
|
---|
36 | * class and the java.io.StreamTokenizer class. It provides a low
|
---|
37 | * level and a high level interface to the tokenizer. The low level
|
---|
38 | * interface consists of the method pair nextToken() and getWord(),
|
---|
39 | * where the first returns the type of token in the parsing process,
|
---|
40 | * and the latter returns the String element itself.
|
---|
41 | * <p>
|
---|
42 | * The high level interface consists of the methods hasNextLine() and
|
---|
43 | * nextLine(). They use the low level interface to parse the data line
|
---|
44 | * by line and create a list of strings from it.
|
---|
45 | * <p>
|
---|
46 | * It is unsure, if it is wise to mix the usage of the high and
|
---|
47 | * the low level interface. For normal usage, the high level interface
|
---|
48 | * should be more comfortable to use and does not provide any
|
---|
49 | * drawbacks.
|
---|
50 | * <p>
|
---|
51 |
|
---|
52 | * An example for the high level interface:
|
---|
53 | * <pre>
|
---|
54 | * try
|
---|
55 | * {
|
---|
56 | * // simple example, tokenizing string, no escape, but quoted
|
---|
57 | * // works:
|
---|
58 | * System.out.println("example 1");
|
---|
59 | * Tokenizer tokenizer = new Tokenizer("text,,,\"another,text\"");
|
---|
60 | * List tokens;
|
---|
61 | * while(tokenizer.hasNextLine())
|
---|
62 | * {
|
---|
63 | * tokens = tokenizer.nextLine();
|
---|
64 | * System.out.println(tokens.get(0)); // prints 'text'
|
---|
65 | * System.out.println(tokens.get(1)); // prints ''
|
---|
66 | * System.out.println(tokens.get(2)); // prints ''
|
---|
67 | * System.out.println(tokens.get(3)); // prints 'another,text'
|
---|
68 | * }
|
---|
69 | *
|
---|
70 | * System.out.println("example 2");
|
---|
71 | * // simple example, tokenizing string, using escape char and
|
---|
72 | * // quoted strings:
|
---|
73 | * tokenizer = new Tokenizer("text,text with\\,comma,,\"another,text\"");
|
---|
74 | * tokenizer.respectEscapedCharacters(true);
|
---|
75 | * while(tokenizer.hasNextLine())
|
---|
76 | * {
|
---|
77 | * tokens = tokenizer.nextLine();
|
---|
78 | * System.out.println(tokens.get(0)); // prints 'text'
|
---|
79 | * System.out.println(tokens.get(1)); // prints 'text with, comma'
|
---|
80 | * System.out.println(tokens.get(2)); // prints ''
|
---|
81 | * System.out.println(tokens.get(3)); // prints 'another,text'
|
---|
82 | * }
|
---|
83 | * }
|
---|
84 | * catch(Exception ioe)
|
---|
85 | * {
|
---|
86 | * ioe.printStackTrace();
|
---|
87 | * }
|
---|
88 | * </pre>
|
---|
89 | * <p>
|
---|
90 | * The advantages compared to the StreamTokenizer class are: Unlike
|
---|
91 | * the StreamTokenizer, this Tokenizer class returns the delimiters as
|
---|
92 | * tokens and therefore may be used to tokenize e.g. comma separated
|
---|
93 | * files with empty fields (the StreamTokenizer handles multiple
|
---|
94 | * delimiters in a row like one delimiter).
|
---|
95 | * <p>
|
---|
96 | * The tokenizer respect quoted words, so the delimiter is ignored if
|
---|
97 | * inside quotes. And it may handle escaped characters (like an
|
---|
98 | * escaped quote character, or an escaped new line). So the line
|
---|
99 | * <code>eric,"he said, \"great!\""</code> returns <code>eric</code>
|
---|
100 | * and <code>he said, "great!"</code> as words.
|
---|
101 | * <p>
|
---|
102 | * Low level interface: The design of the Tokenizer allows to get
|
---|
103 | * empty columns as well as treat multiple delimiters in a row as one
|
---|
104 | * delimiter. For the first approach trigger the values on every
|
---|
105 | * DELIMITER and EOF token whereas for the second, trigger only on
|
---|
106 | * WORD tokens.
|
---|
107 | * <p>
|
---|
108 | * If one wants to be informed about empty words as well, use the
|
---|
109 | * Tokenizer like in the following code fragment:
|
---|
110 | * <pre>
|
---|
111 | * Tokenizer tokenizer = new Tokenizer("text,,,another text");
|
---|
112 | * String word = "";
|
---|
113 | * int token;
|
---|
114 | * while((token = tokenizer.nextToken()) != Tokenizer.EOF)
|
---|
115 | * {
|
---|
116 | * switch(token)
|
---|
117 | * {
|
---|
118 | * case Tokenizer.EOL:
|
---|
119 | * System.out.println("word: "+word);
|
---|
120 | * word = "";
|
---|
121 | * System.out.println("-------------");
|
---|
122 | * break;
|
---|
123 | * case Tokenizer.WORD:
|
---|
124 | * word = tokenizer.getWord();
|
---|
125 | * break;
|
---|
126 | * case Tokenizer.QUOTED_WORD:
|
---|
127 | * word = tokenizer.getWord() + " (quoted)";
|
---|
128 | * break;
|
---|
129 | * case Tokenizer.DELIMITER:
|
---|
130 | * System.out.println("word: "+word);
|
---|
131 | * word = "";
|
---|
132 | * break;
|
---|
133 | * default:
|
---|
134 | * System.err.println("Unknown Token: "+token);
|
---|
135 | * }
|
---|
136 | * }
|
---|
137 | * </pre>
|
---|
138 | * In this example, if the delimiter is set to a comma, a line like
|
---|
139 | * <code>column1,,,"column4,partofcolumn4"</code> would be treated correctly.
|
---|
140 | * <p>
|
---|
141 | * This tokenizer uses the LF character as end of line characters. It
|
---|
142 | * ignores any CR characters, so it can be used in windows
|
---|
143 | * environments as well.
|
---|
144 | *
|
---|
145 | * @author Christof Dallermassl
|
---|
146 | * @version $Revision: 1.6 $
|
---|
147 | */
|
---|
148 |
|
---|
149 | public class Tokenizer
|
---|
150 | {
|
---|
151 | /** the reader to read from */
|
---|
152 | protected PushbackReader reader_;
|
---|
153 | /** the buffer to create the tokens */
|
---|
154 | protected StringBuffer buffer_;
|
---|
155 | /** all characters in this string are used as delimiters */
|
---|
156 | protected String delimiters_ = ",";
|
---|
157 | /** the escape character */
|
---|
158 | protected int escapeChar_ = '\\';
|
---|
159 | /** the quote character */
|
---|
160 | protected int quoteChar_ = '"';
|
---|
161 |
|
---|
162 | /** if true, characters are treated as escaped */
|
---|
163 | protected boolean escapeMode_ = false;
|
---|
164 |
|
---|
165 | /** if true, end of line is respected */
|
---|
166 | protected boolean eolIsSignificant_ = true;
|
---|
167 | /** if true, escape characters are respected */
|
---|
168 | protected boolean respectEscapedChars_ = false;
|
---|
169 | /** if true, quoted words are respected */
|
---|
170 | protected boolean respectQuotedWords_ = true;
|
---|
171 |
|
---|
172 | /** line count */
|
---|
173 | protected int lineCount_ = 1;
|
---|
174 |
|
---|
175 | /** end of file marker */
|
---|
176 | protected boolean eofReached_ = false;
|
---|
177 |
|
---|
178 | /** the last token that was found */
|
---|
179 | protected int lastToken_ = NOT_STARTED;
|
---|
180 |
|
---|
181 | /** end of file token */
|
---|
182 | public static final int EOF = -1;
|
---|
183 | /** end of line token */
|
---|
184 | public static final int EOL = 0;
|
---|
185 | /** word token */
|
---|
186 | public static final int WORD = 1;
|
---|
187 | /** quoted word token */
|
---|
188 | public static final int QUOTED_WORD = 2;
|
---|
189 | /** delimiter token */
|
---|
190 | public static final int DELIMITER = 3;
|
---|
191 | /** error token */
|
---|
192 | public static final int ERROR = 4;
|
---|
193 | /** not started token */
|
---|
194 | public static final int NOT_STARTED = 5;
|
---|
195 |
|
---|
196 |
|
---|
197 | //----------------------------------------------------------------------
|
---|
198 | /**
|
---|
199 | * Creates a tokenizer that reads from the given string. It uses the
|
---|
200 | * comma as delimiter, does not respect escape characters but respects
|
---|
201 | * quoted words.
|
---|
202 | *
|
---|
203 | * @param string the string to read from.
|
---|
204 | */
|
---|
205 | public Tokenizer(String string)
|
---|
206 | {
|
---|
207 | this(new StringReader(string));
|
---|
208 | }
|
---|
209 |
|
---|
210 | //----------------------------------------------------------------------
|
---|
211 | /**
|
---|
212 | * Creates a tokenizer that reads from the given string. All
|
---|
213 | * characters in the given delimiters string are used as
|
---|
214 | * delimiter. The tokenizer does not respect escape characters but
|
---|
215 | * respects quoted words.
|
---|
216 | *
|
---|
217 | * @param string the string to read from.
|
---|
218 | * @param delimiters the delimiters to use.
|
---|
219 | */
|
---|
220 | public Tokenizer(String string, String delimiters)
|
---|
221 | {
|
---|
222 | this(new StringReader(string));
|
---|
223 | setDelimiters(delimiters);
|
---|
224 | }
|
---|
225 |
|
---|
226 | //----------------------------------------------------------------------
|
---|
227 | /**
|
---|
228 | * Creates a tokenizer that reads from the given reader. It uses the
|
---|
229 | * comma as delimiter, does not respect escape characters but respects
|
---|
230 | * quoted words.
|
---|
231 | *
|
---|
232 | * @param reader the reader to read from.
|
---|
233 | */
|
---|
234 | public Tokenizer(Reader reader)
|
---|
235 | {
|
---|
236 | reader_ = new PushbackReader(reader,2);
|
---|
237 | buffer_ = new StringBuffer();
|
---|
238 | }
|
---|
239 |
|
---|
240 | //----------------------------------------------------------------------
|
---|
241 | /**
|
---|
242 | * Set the delimiter character. The default is the comma.
|
---|
243 | *
|
---|
244 | * @param delimiterChar the delimiter character.
|
---|
245 | */
|
---|
246 | public void setDelimiter(int delimiterChar)
|
---|
247 | {
|
---|
248 | delimiters_ = new String(new char[]{(char)delimiterChar});
|
---|
249 | }
|
---|
250 |
|
---|
251 | //----------------------------------------------------------------------
|
---|
252 | /**
|
---|
253 | * Get the first delimiter character.
|
---|
254 | *
|
---|
255 | * @return the delimiter character.
|
---|
256 | * @deprecated use the getDelimiters() method now
|
---|
257 | */
|
---|
258 | public int getDelimiter()
|
---|
259 | {
|
---|
260 | return(delimiters_.charAt(0));
|
---|
261 | }
|
---|
262 |
|
---|
263 | //----------------------------------------------------------------------
|
---|
264 | /**
|
---|
265 | * Set the delimiter characters. All characters in the delimiters are
|
---|
266 | * used as delimiter.
|
---|
267 | *
|
---|
268 | * @param delimiters the delimiter characters.
|
---|
269 | */
|
---|
270 | public void setDelimiters(String delimiters)
|
---|
271 | {
|
---|
272 | delimiters_ = delimiters;
|
---|
273 | }
|
---|
274 |
|
---|
275 | //----------------------------------------------------------------------
|
---|
276 | /**
|
---|
277 | * Get the delimiter character.
|
---|
278 | *
|
---|
279 | * @return the delimiter character.
|
---|
280 | */
|
---|
281 | public String getDelimiters()
|
---|
282 | {
|
---|
283 | return(delimiters_);
|
---|
284 | }
|
---|
285 |
|
---|
286 | //----------------------------------------------------------------------
|
---|
287 | /**
|
---|
288 | * Set the escape character. The default is the backslash.
|
---|
289 | *
|
---|
290 | * @param escapeChar the escape character.
|
---|
291 | */
|
---|
292 | public void setEscapeChar(int escapeChar)
|
---|
293 | {
|
---|
294 | escapeChar_ = escapeChar;
|
---|
295 | }
|
---|
296 |
|
---|
297 | //----------------------------------------------------------------------
|
---|
298 | /**
|
---|
299 | * Get the escape character.
|
---|
300 | *
|
---|
301 | * @return the escape character.
|
---|
302 | */
|
---|
303 | public int getEscapeChar()
|
---|
304 | {
|
---|
305 | return(escapeChar_);
|
---|
306 | }
|
---|
307 |
|
---|
308 | //----------------------------------------------------------------------
|
---|
309 | /**
|
---|
310 | * If escape characters should be respected, set the param to
|
---|
311 | * <code>true</code>. The default is to ignore escape characters.
|
---|
312 | *
|
---|
313 | * @param respectEscaped If escape characters should be respected,
|
---|
314 | * set the param to <code>true</code>.
|
---|
315 | */
|
---|
316 | public void respectEscapedCharacters(boolean respectEscaped)
|
---|
317 | {
|
---|
318 | respectEscapedChars_ = respectEscaped;
|
---|
319 | }
|
---|
320 |
|
---|
321 | //----------------------------------------------------------------------
|
---|
322 | /**
|
---|
323 | * Returns <code>true</code>, if escape character is respected.
|
---|
324 | *
|
---|
325 | * @return <code>true</code>, if escape character is respected.
|
---|
326 | */
|
---|
327 | public boolean respectEscapedCharacters()
|
---|
328 | {
|
---|
329 | return(respectEscapedChars_);
|
---|
330 | }
|
---|
331 |
|
---|
332 | //----------------------------------------------------------------------
|
---|
333 | /**
|
---|
334 | * Get the quote character.
|
---|
335 | *
|
---|
336 | * @return the quote character.
|
---|
337 | */
|
---|
338 | public int getQuoteChar()
|
---|
339 | {
|
---|
340 | return (quoteChar_);
|
---|
341 | }
|
---|
342 |
|
---|
343 | //----------------------------------------------------------------------
|
---|
344 | /**
|
---|
345 | * Set the quote character. The default is the double quote.
|
---|
346 | *
|
---|
347 | * @param quoteChar the quote character.
|
---|
348 | */
|
---|
349 | public void setQuoteChar(int quoteChar)
|
---|
350 | {
|
---|
351 | quoteChar_ = quoteChar;
|
---|
352 | }
|
---|
353 |
|
---|
354 | //----------------------------------------------------------------------
|
---|
355 | /**
|
---|
356 | * If quoted words should be respected, set the param to
|
---|
357 | * <code>true</code>. The default is to respect quoted words.
|
---|
358 | *
|
---|
359 | * @param respectQuotes If quoted words should be respected,
|
---|
360 | * set the param to <code>true</code>.
|
---|
361 | */
|
---|
362 | public void respectQuotedWords(boolean respectQuotes)
|
---|
363 | {
|
---|
364 | respectQuotedWords_ = respectQuotes;
|
---|
365 | }
|
---|
366 |
|
---|
367 | //----------------------------------------------------------------------
|
---|
368 | /**
|
---|
369 | * Returns <code>true</code>, if quoted words are respected.
|
---|
370 | *
|
---|
371 | * @return <code>true</code>, if quoted words are respected.
|
---|
372 | */
|
---|
373 | public boolean respectQuotedWords()
|
---|
374 | {
|
---|
375 | return(respectQuotedWords_);
|
---|
376 | }
|
---|
377 |
|
---|
378 | //----------------------------------------------------------------------
|
---|
379 | /**
|
---|
380 | * If set to <code>true</code> the end of line is signaled by the EOL
|
---|
381 | * token. If set to <code>false</code> end of line is treated as a
|
---|
382 | * normal delimiter. The default value is true;
|
---|
383 | *
|
---|
384 | * @param significant if the end of line is treated as a special token
|
---|
385 | * or as a delimiter.
|
---|
386 | */
|
---|
387 | public void eolIsSignificant(boolean significant)
|
---|
388 | {
|
---|
389 | eolIsSignificant_ = significant;
|
---|
390 | }
|
---|
391 |
|
---|
392 | //----------------------------------------------------------------------
|
---|
393 | /**
|
---|
394 | * Returns <code>true</code>, if in case of an end of line detected,
|
---|
395 | * an EOL token is returned. If <code>false</code>, the end of line is
|
---|
396 | * treated as a normal delimiter.
|
---|
397 | *
|
---|
398 | * @return <code>true</code>, if in case of an end of line detected,
|
---|
399 | * an EOL token is returned. If <code>false</code>, the end of line is
|
---|
400 | * treated as a normal delimiter.
|
---|
401 | */
|
---|
402 | public boolean isEolSignificant()
|
---|
403 | {
|
---|
404 | return(eolIsSignificant_);
|
---|
405 | }
|
---|
406 |
|
---|
407 |
|
---|
408 | //----------------------------------------------------------------------
|
---|
409 | /**
|
---|
410 | * Returns the current line number of the reader.
|
---|
411 | *
|
---|
412 | * @return the current line number of the reader.
|
---|
413 | */
|
---|
414 | public int getLineNumber()
|
---|
415 | {
|
---|
416 | return(lineCount_);
|
---|
417 | }
|
---|
418 |
|
---|
419 | //----------------------------------------------------------------------
|
---|
420 | /**
|
---|
421 | * Returns the value of the token. If the token was of the type WORD,
|
---|
422 | * the word is returned.
|
---|
423 | *
|
---|
424 | * @return the value of the token.
|
---|
425 | */
|
---|
426 | public String getWord()
|
---|
427 | {
|
---|
428 | return(buffer_.toString());
|
---|
429 | }
|
---|
430 |
|
---|
431 | //----------------------------------------------------------------------
|
---|
432 | /**
|
---|
433 | * Returns the last token that was returned from the nextToken() method.
|
---|
434 | *
|
---|
435 | * @return the last token.
|
---|
436 | */
|
---|
437 | public int getLastToken()
|
---|
438 | {
|
---|
439 | return(lastToken_);
|
---|
440 | }
|
---|
441 |
|
---|
442 | //----------------------------------------------------------------------
|
---|
443 | /**
|
---|
444 | * Returns true, if the given character is seen as a delimiter. This
|
---|
445 | * method respects escape_mode, so if the escape character was found
|
---|
446 | * before, it has to act accordingly (usually, return false, even if
|
---|
447 | * the character is a delimiter).
|
---|
448 | *
|
---|
449 | * @param character the character to check for delimiter
|
---|
450 | * @return true, if the given character is seen as a delimiter.
|
---|
451 | */
|
---|
452 | protected boolean isDelimiter(int character)
|
---|
453 | {
|
---|
454 | // check for escape mode:
|
---|
455 | if(escapeMode_)
|
---|
456 | return(false);
|
---|
457 |
|
---|
458 | return(delimiters_.indexOf(character) >= 0);
|
---|
459 | }
|
---|
460 |
|
---|
461 | //----------------------------------------------------------------------
|
---|
462 | /**
|
---|
463 | * Returns true, if the given character is seen as a quote
|
---|
464 | * character. This method respects escape_mode, so if the escape
|
---|
465 | * character was found before, it has to act accordingly (usually,
|
---|
466 | * return false, even if the character is a quote character).
|
---|
467 | *
|
---|
468 | * @param character the character to check for quote.
|
---|
469 | * @return true, if the given character is seen as a quote character.
|
---|
470 | */
|
---|
471 | protected boolean isQuoteChar(int character)
|
---|
472 | {
|
---|
473 | if(!respectQuotedWords_)
|
---|
474 | return(false);
|
---|
475 |
|
---|
476 | // check for escape mode:
|
---|
477 | if(escapeMode_)
|
---|
478 | return(false);
|
---|
479 |
|
---|
480 | return(character == quoteChar_);
|
---|
481 | }
|
---|
482 |
|
---|
483 | //----------------------------------------------------------------------
|
---|
484 | /**
|
---|
485 | * Returns true, if the given character is seen as a escape
|
---|
486 | * character. This method respects escape_mode, so if the escape
|
---|
487 | * character was found before, it has to act accordingly (usually,
|
---|
488 | * return false, even if the character is a escape character).
|
---|
489 | * @param character the character to check for escape character.
|
---|
490 | * @return true, if the given character is seen as a escape character.
|
---|
491 | */
|
---|
492 | protected boolean isEscapeChar(int character)
|
---|
493 | {
|
---|
494 | if(!respectEscapedChars_)
|
---|
495 | return(false);
|
---|
496 |
|
---|
497 | // check for escape mode:
|
---|
498 | if(escapeMode_)
|
---|
499 | return(false);
|
---|
500 |
|
---|
501 | return(character == escapeChar_);
|
---|
502 | }
|
---|
503 |
|
---|
504 | //----------------------------------------------------------------------
|
---|
505 | /**
|
---|
506 | * Returns true, if the given character is seen as a end of line
|
---|
507 | * character. This method respects end of line_mode, so if the end of
|
---|
508 | * line character was found before, it has to act accordingly
|
---|
509 | * (usually, return false, even if the character is a end of line
|
---|
510 | * character).
|
---|
511 | * @param character the character to check for end of line.
|
---|
512 | * @return true, if the given character is seen as a end of line
|
---|
513 | * character.
|
---|
514 | */
|
---|
515 | protected boolean isEndOfLine(int character)
|
---|
516 | {
|
---|
517 | // check for escape mode:
|
---|
518 | if(escapeMode_)
|
---|
519 | {
|
---|
520 | if(character == '\n') // add line count, even if in escape mode!
|
---|
521 | lineCount_++;
|
---|
522 | return(false);
|
---|
523 | }
|
---|
524 | if(character == -1)
|
---|
525 | eofReached_ = true;
|
---|
526 |
|
---|
527 | return((character=='\n') || (character=='\r') || (character == -1));
|
---|
528 | }
|
---|
529 |
|
---|
530 | //----------------------------------------------------------------------
|
---|
531 | /**
|
---|
532 | * Closes the tokenizer (and the reader is uses internally).
|
---|
533 | *
|
---|
534 | * @exception IOException if an error occurred.
|
---|
535 | */
|
---|
536 | public void close()
|
---|
537 | throws IOException
|
---|
538 | {
|
---|
539 | reader_.close();
|
---|
540 | }
|
---|
541 |
|
---|
542 | //----------------------------------------------------------------------
|
---|
543 | /**
|
---|
544 | * Reads and returns the next character from the reader and checks for
|
---|
545 | * the escape character. If an escape character is read, a flag is set
|
---|
546 | * and the next character is read. A newline following the escape
|
---|
547 | * character is ignored.
|
---|
548 | *
|
---|
549 | * @return the next character.
|
---|
550 | * @exception IOException if an error occurred.
|
---|
551 | */
|
---|
552 | protected int readNextChar()
|
---|
553 | throws IOException
|
---|
554 | {
|
---|
555 | int next_char = reader_.read();
|
---|
556 | if(escapeMode_)
|
---|
557 | {
|
---|
558 | escapeMode_ = false;
|
---|
559 | }
|
---|
560 | else
|
---|
561 | {
|
---|
562 | if(isEscapeChar(next_char))
|
---|
563 | {
|
---|
564 | // ignore escape char itself:
|
---|
565 | next_char = reader_.read();
|
---|
566 |
|
---|
567 | // check for newline and ignore it:
|
---|
568 | if(isEndOfLine(next_char))
|
---|
569 | {
|
---|
570 | lineCount_++;
|
---|
571 | next_char = reader_.read();
|
---|
572 | // ignore CR:
|
---|
573 | if(next_char == '\r')
|
---|
574 | {
|
---|
575 | next_char = readNextChar();
|
---|
576 | }
|
---|
577 | }
|
---|
578 | escapeMode_ = true;
|
---|
579 | }
|
---|
580 | }
|
---|
581 | // ignore CR:
|
---|
582 | if(next_char == '\r')
|
---|
583 | {
|
---|
584 | next_char = readNextChar();
|
---|
585 | }
|
---|
586 | return(next_char);
|
---|
587 | }
|
---|
588 |
|
---|
589 | //----------------------------------------------------------------------
|
---|
590 | /**
|
---|
591 | * Returns the next token from the reader. The token's value may be
|
---|
592 | * WORD, QUOTED_WORD, EOF, EOL, or DELIMITER. In the case or WORD or
|
---|
593 | * QUOTED_WORD the actual word can be obtained by the use of the
|
---|
594 | * getWord method.
|
---|
595 | *
|
---|
596 | * @return the next token.
|
---|
597 | * @exception IOException if an error occurred.
|
---|
598 | */
|
---|
599 | public int nextToken()
|
---|
600 | throws IOException
|
---|
601 | {
|
---|
602 | buffer_.setLength(0);
|
---|
603 |
|
---|
604 | int next_char;
|
---|
605 | next_char = readNextChar();
|
---|
606 |
|
---|
607 | // handle EOF:
|
---|
608 | if(eofReached_)
|
---|
609 | {
|
---|
610 | lastToken_ = EOF;
|
---|
611 | return(EOF);
|
---|
612 | }
|
---|
613 |
|
---|
614 | // handle EOL:
|
---|
615 | if(isEndOfLine(next_char))
|
---|
616 | {
|
---|
617 | lineCount_++;
|
---|
618 | if(eolIsSignificant_)
|
---|
619 | {
|
---|
620 | lastToken_ = EOL;
|
---|
621 | return(EOL);
|
---|
622 | }
|
---|
623 | else
|
---|
624 | {
|
---|
625 | lastToken_ = DELIMITER;
|
---|
626 | return(DELIMITER);
|
---|
627 | }
|
---|
628 | }
|
---|
629 |
|
---|
630 | // handle DELIMITER
|
---|
631 | if(isDelimiter(next_char))
|
---|
632 | {
|
---|
633 | lastToken_ = DELIMITER;
|
---|
634 | return(DELIMITER);
|
---|
635 | }
|
---|
636 |
|
---|
637 | // handle quoted words:
|
---|
638 | if(isQuoteChar(next_char))
|
---|
639 | {
|
---|
640 | while(true)
|
---|
641 | {
|
---|
642 | next_char = readNextChar();
|
---|
643 | if(isEndOfLine(next_char))
|
---|
644 | {
|
---|
645 | lastToken_ = ERROR;
|
---|
646 | return(ERROR);
|
---|
647 | }
|
---|
648 | else
|
---|
649 | {
|
---|
650 | if(isQuoteChar(next_char))
|
---|
651 | {
|
---|
652 | lastToken_ = QUOTED_WORD;
|
---|
653 | return(QUOTED_WORD);
|
---|
654 | }
|
---|
655 |
|
---|
656 | // no special char, then append to buffer:
|
---|
657 | buffer_.append((char)next_char);
|
---|
658 | }
|
---|
659 | }
|
---|
660 | }
|
---|
661 |
|
---|
662 | // handle 'normal' words:
|
---|
663 | while(true)
|
---|
664 | {
|
---|
665 | buffer_.append((char)next_char);
|
---|
666 | next_char = readNextChar();
|
---|
667 | if(isDelimiter(next_char) || isEndOfLine(next_char))
|
---|
668 | {
|
---|
669 | reader_.unread(next_char);
|
---|
670 | lastToken_ = WORD;
|
---|
671 | return(WORD);
|
---|
672 | }
|
---|
673 | }
|
---|
674 | }
|
---|
675 |
|
---|
676 | //----------------------------------------------------------------------
|
---|
677 | /**
|
---|
678 | * Returns true, if the tokenizer can return another line.
|
---|
679 | *
|
---|
680 | * @return true, if the tokenizer can return another line.
|
---|
681 | * @exception IOException if an error occurred.
|
---|
682 | */
|
---|
683 | public boolean hasNextLine()
|
---|
684 | throws IOException
|
---|
685 | {
|
---|
686 | if(lastToken_ == EOF)
|
---|
687 | return(false);
|
---|
688 |
|
---|
689 | if((lastToken_ == EOL) || (lastToken_ == NOT_STARTED))
|
---|
690 | {
|
---|
691 | int next_char = readNextChar();
|
---|
692 | if(next_char == -1)
|
---|
693 | return(false);
|
---|
694 |
|
---|
695 | reader_.unread(next_char);
|
---|
696 | }
|
---|
697 | return(true);
|
---|
698 | }
|
---|
699 |
|
---|
700 |
|
---|
701 | //----------------------------------------------------------------------
|
---|
702 | /**
|
---|
703 | * Returns a list of elements (Strings) from the next line of the
|
---|
704 | * tokenizer. If there are multiple delimiters without any values in
|
---|
705 | * between, empty (zero length) strings are added to the list. They
|
---|
706 | * may be removed by the use of the {@link
|
---|
707 | * #removeZeroLengthElements(List)} method.
|
---|
708 | *
|
---|
709 | * @return a list of elements (Strings) from the next line of the
|
---|
710 | * tokenizer.
|
---|
711 | * @exception IOException if an error occurred.
|
---|
712 | */
|
---|
713 | public List<String> nextLine()
|
---|
714 | throws IOException
|
---|
715 | {
|
---|
716 | int token = nextToken();
|
---|
717 | List<String> list = new ArrayList<>();
|
---|
718 | String word = "";
|
---|
719 | // while(token != Tokenizer.EOF)
|
---|
720 | while(true)
|
---|
721 | {
|
---|
722 | switch(token)
|
---|
723 | {
|
---|
724 | case Tokenizer.WORD:
|
---|
725 | word = getWord();
|
---|
726 | break;
|
---|
727 | case Tokenizer.QUOTED_WORD:
|
---|
728 | word = getWord();
|
---|
729 | break;
|
---|
730 | case Tokenizer.DELIMITER:
|
---|
731 | list.add(word);
|
---|
732 | word = "";
|
---|
733 | break;
|
---|
734 | case Tokenizer.EOL:
|
---|
735 | case Tokenizer.EOF:
|
---|
736 | list.add(word);
|
---|
737 | return(list);
|
---|
738 | default:
|
---|
739 | System.err.println("Unknown Token: "+token);
|
---|
740 | }
|
---|
741 | token = nextToken();
|
---|
742 | }
|
---|
743 | // return(list);
|
---|
744 | }
|
---|
745 |
|
---|
746 | //----------------------------------------------------------------------
|
---|
747 | /**
|
---|
748 | * This helper method removes all zero length elements from the given
|
---|
749 | * list and returns it. The given list is not changed!
|
---|
750 | *
|
---|
751 | * @param list the list of String objects to remove the zero elements from.
|
---|
752 | * @return a copy of the given list where all zero length elements are removed.
|
---|
753 | */
|
---|
754 | public static List<String> removeZeroLengthElements(List<String> list)
|
---|
755 | {
|
---|
756 | return removeZeroLengthElements(list, false);
|
---|
757 | }
|
---|
758 |
|
---|
759 | //----------------------------------------------------------------------
|
---|
760 | /**
|
---|
761 | * This helper method trims all elements and removes all zero length
|
---|
762 | * (length is taken after trimming leading and trailing spaces) elements from the given
|
---|
763 | * list and returns it. This method copies the (trimmed and) non-zero elements to a
|
---|
764 | * new list.
|
---|
765 | *
|
---|
766 | * @param list the list of String objects to remove the zero elements from.
|
---|
767 | * @param trim if set to <code>true</code>, all leading and trailing spaces are removed from
|
---|
768 | * the elements. This is done, before the length is compared to zero (and the element
|
---|
769 | * may be removed if the length is zero). If set to <code>true</code>, elements
|
---|
770 | * that only consist of spaces are removed as well!
|
---|
771 | * @return the list where all zero length elements are remove.
|
---|
772 | */
|
---|
773 | public static List<String> removeZeroLengthElements(List<String> list, boolean trim)
|
---|
774 | {
|
---|
775 | Iterator<String> iterator = list.iterator();
|
---|
776 | String value;
|
---|
777 | List<String> new_list = new ArrayList<>();
|
---|
778 | while(iterator.hasNext())
|
---|
779 | {
|
---|
780 | value = iterator.next();
|
---|
781 | if (trim)
|
---|
782 | value = value.trim();
|
---|
783 | if(value.length() != 0)
|
---|
784 | new_list.add(value);
|
---|
785 | }
|
---|
786 | return(new_list);
|
---|
787 | }
|
---|
788 | }
|
---|