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1 package org.apache.velocity.runtime.parser;
2
3
13
14
18
19 public final class VelocityCharStream
20 implements CharStream
21 {
22 public static final boolean staticFlag = false;
23 int bufsize;
24 int available;
25 int tokenBegin;
26 public int bufpos = -1;
27 private int bufline[];
28 private int bufcolumn[];
29
30 private int column = 0;
31 private int line = 1;
32
33 private boolean prevCharIsCR = false;
34 private boolean prevCharIsLF = false;
35
36 private java.io.Reader  inputStream;
37
38 private char[] buffer;
39 private int maxNextCharInd = 0;
40 private int inBuf = 0;
41
42 private final void ExpandBuff(boolean wrapAround)
43 {
44 char[] newbuffer = new char[bufsize + 2048];
45 int newbufline[] = new int[bufsize + 2048];
46 int newbufcolumn[] = new int[bufsize + 2048];
47
48 try
49 {
50 if (wrapAround)
51 {
52 System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
53 System.arraycopy(buffer, 0, newbuffer,
54 bufsize - tokenBegin, bufpos);
55 buffer = newbuffer;
56
57 System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
58 System.arraycopy(bufline, 0, newbufline, bufsize - tokenBegin, bufpos);
59 bufline = newbufline;
60
61 System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
62 System.arraycopy(bufcolumn, 0, newbufcolumn, bufsize - tokenBegin, bufpos);
63 bufcolumn = newbufcolumn;
64
65 maxNextCharInd = (bufpos += (bufsize - tokenBegin));
66 }
67 else
68 {
69 System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
70 buffer = newbuffer;
71
72 System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
73 bufline = newbufline;
74
75 System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
76 bufcolumn = newbufcolumn;
77
78 maxNextCharInd = (bufpos -= tokenBegin);
79 }
80 }
81 catch (Throwable t)
82 {
83 throw new Error (t.getMessage());
84 }
85
86
87 bufsize += 2048;
88 available = bufsize;
89 tokenBegin = 0;
90 }
91
92 private final void FillBuff() throws java.io.IOException
93 {
94 if (maxNextCharInd == available)
95 {
96 if (available == bufsize)
97 {
98 if (tokenBegin > 2048)
99 {
100 bufpos = maxNextCharInd = 0;
101 available = tokenBegin;
102 }
103 else if (tokenBegin < 0)
104 bufpos = maxNextCharInd = 0;
105 else
106 ExpandBuff(false);
107 }
108 else if (available > tokenBegin)
109 available = bufsize;
110 else if ((tokenBegin - available) < 2048)
111 ExpandBuff(true);
112 else
113 available = tokenBegin;
114 }
115
116 int i;
117 try {
118 if ((i = inputStream.read(buffer, maxNextCharInd,
119 available - maxNextCharInd)) == -1)
120 {
121 inputStream.close();
122 throw new java.io.IOException ();
123 }
124 else
125 maxNextCharInd += i;
126 return;
127 }
128 catch(java.io.IOException e) {
129 --bufpos;
130 backup(0);
131 if (tokenBegin == -1)
132 tokenBegin = bufpos;
133 throw e;
134 }
135 }
136
137 public final char BeginToken() throws java.io.IOException
138 {
139 tokenBegin = -1;
140 char c = readChar();
141 tokenBegin = bufpos;
142
143 return c;
144 }
145
146 private final void UpdateLineColumn(char c)
147 {
148 column++;
149
150 if (prevCharIsLF)
151 {
152 prevCharIsLF = false;
153 line += (column = 1);
154 }
155 else if (prevCharIsCR)
156 {
157 prevCharIsCR = false;
158 if (c == '\n')
159 {
160 prevCharIsLF = true;
161 }
162 else
163 line += (column = 1);
164 }
165
166 switch (c)
167 {
168 case '\r' :
169 prevCharIsCR = true;
170 break;
171 case '\n' :
172 prevCharIsLF = true;
173 break;
174 case '\t' :
175 column--;
176 column += (8 - (column & 07));
177 break;
178 default :
179 break;
180 }
181
182 bufline[bufpos] = line;
183 bufcolumn[bufpos] = column;
184 }
185
186 public final char readChar() throws java.io.IOException
187 {
188 if (inBuf > 0)
189 {
190 --inBuf;
191
192
195 return buffer[(bufpos == bufsize - 1) ? (bufpos = 0) : ++bufpos];
196 }
197
198 if (++bufpos >= maxNextCharInd)
199 FillBuff();
200
201
204 char c = buffer[bufpos];
205
206 UpdateLineColumn(c);
207 return (c);
208 }
209
210
214
215 public final int getColumn() {
216 return bufcolumn[bufpos];
217 }
218
219
223
224 public final int getLine() {
225 return bufline[bufpos];
226 }
227
228 public final int getEndColumn() {
229 return bufcolumn[bufpos];
230 }
231
232 public final int getEndLine() {
233 return bufline[bufpos];
234 }
235
236 public final int getBeginColumn() {
237 return bufcolumn[tokenBegin];
238 }
239
240 public final int getBeginLine() {
241 return bufline[tokenBegin];
242 }
243
244 public final void backup(int amount) {
245
246 inBuf += amount;
247 if ((bufpos -= amount) < 0)
248 bufpos += bufsize;
249 }
250
251 public VelocityCharStream(java.io.Reader dstream, int startline,
252 int startcolumn, int buffersize)
253 {
254 inputStream = dstream;
255 line = startline;
256 column = startcolumn - 1;
257
258 available = bufsize = buffersize;
259 buffer = new char[buffersize];
260 bufline = new int[buffersize];
261 bufcolumn = new int[buffersize];
262 }
263
264 public VelocityCharStream(java.io.Reader dstream, int startline,
265 int startcolumn)
266 {
267 this(dstream, startline, startcolumn, 4096);
268 }
269 public void ReInit(java.io.Reader dstream, int startline,
270 int startcolumn, int buffersize)
271 {
272 inputStream = dstream;
273 line = startline;
274 column = startcolumn - 1;
275
276 if (buffer == null || buffersize != buffer.length)
277 {
278 available = bufsize = buffersize;
279 buffer = new char[buffersize];
280 bufline = new int[buffersize];
281 bufcolumn = new int[buffersize];
282 }
283 prevCharIsLF = prevCharIsCR = false;
284 tokenBegin = inBuf = maxNextCharInd = 0;
285 bufpos = -1;
286 }
287
288 public void ReInit(java.io.Reader dstream, int startline,
289 int startcolumn)
290 {
291 ReInit(dstream, startline, startcolumn, 4096);
292 }
293 public VelocityCharStream(java.io.InputStream dstream, int startline,
294 int startcolumn, int buffersize)
295 {
296 this(new java.io.InputStreamReader (dstream), startline, startcolumn, 4096);
297 }
298
299 public VelocityCharStream(java.io.InputStream dstream, int startline,
300 int startcolumn)
301 {
302 this(dstream, startline, startcolumn, 4096);
303 }
304
305 public void ReInit(java.io.InputStream dstream, int startline,
306 int startcolumn, int buffersize)
307 {
308 ReInit(new java.io.InputStreamReader (dstream), startline, startcolumn, 4096);
309 }
310 public void ReInit(java.io.InputStream dstream, int startline,
311 int startcolumn)
312 {
313 ReInit(dstream, startline, startcolumn, 4096);
314 }
315 public final String GetImage()
316 {
317 if (bufpos >= tokenBegin)
318 return new String (buffer, tokenBegin, bufpos - tokenBegin + 1);
319 else
320 return new String (buffer, tokenBegin, bufsize - tokenBegin) +
321 new String (buffer, 0, bufpos + 1);
322 }
323
324 public final char[] GetSuffix(int len)
325 {
326 char[] ret = new char[len];
327
328 if ((bufpos + 1) >= len)
329 System.arraycopy(buffer, bufpos - len + 1, ret, 0, len);
330 else
331 {
332 System.arraycopy(buffer, bufsize - (len - bufpos - 1), ret, 0,
333 len - bufpos - 1);
334 System.arraycopy(buffer, 0, ret, len - bufpos - 1, bufpos + 1);
335 }
336
337 return ret;
338 }
339
340 public void Done()
341 {
342 buffer = null;
343 bufline = null;
344 bufcolumn = null;
345 }
346
347
350 public void adjustBeginLineColumn(int newLine, int newCol)
351 {
352 int start = tokenBegin;
353 int len;
354
355 if (bufpos >= tokenBegin)
356 {
357 len = bufpos - tokenBegin + inBuf + 1;
358 }
359 else
360 {
361 len = bufsize - tokenBegin + bufpos + 1 + inBuf;
362 }
363
364 int i = 0, j = 0, k = 0;
365 int nextColDiff = 0, columnDiff = 0;
366
367 while (i < len &&
368 bufline[j = start % bufsize] == bufline[k = ++start % bufsize])
369 {
370 bufline[j] = newLine;
371 nextColDiff = columnDiff + bufcolumn[k] - bufcolumn[j];
372 bufcolumn[j] = newCol + columnDiff;
373 columnDiff = nextColDiff;
374 i++;
375 }
376
377 if (i < len)
378 {
379 bufline[j] = newLine++;
380 bufcolumn[j] = newCol + columnDiff;
381
382 while (i++ < len)
383 {
384 if (bufline[j = start % bufsize] != bufline[++start % bufsize])
385 bufline[j] = newLine++;
386 else
387 bufline[j] = newLine;
388 }
389 }
390
391 line = bufline[j];
392 column = bufcolumn[j];
393 }
394
395 }
396 |
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