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1   /* Generated By:JavaCC: Do not edit this line. SimpleCharStream.java Version 3.0 */
2   package org.apache.commons.jxpath.ri.parser;
3   
4   /**
5    * An implementation of interface CharStream, where the stream is assumed to
6    * contain only ASCII characters (without unicode processing).
7    */
8   
9   public class SimpleCharStream
10  {
11    public static final boolean staticFlag = false;
12    int bufsize;
13    int available;
14    int tokenBegin;
15    public int bufpos = -1;
16    protected int bufline[];
17    protected int bufcolumn[];
18  
19    protected int column = 0;
20    protected int line = 1;
21  
22    protected boolean prevCharIsCR = false;
23    protected boolean prevCharIsLF = false;
24  
25    protected java.io.Reader inputStream;
26  
27    protected char[] buffer;
28    protected int maxNextCharInd = 0;
29    protected int inBuf = 0;
30  
31    protected void ExpandBuff(boolean wrapAround)
32    {
33       char[] newbuffer = new char[bufsize + 2048];
34       int newbufline[] = new int[bufsize + 2048];
35       int newbufcolumn[] = new int[bufsize + 2048];
36  
37       try
38       {
39          if (wrapAround)
40          {
41             System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
42             System.arraycopy(buffer, 0, newbuffer,
43                                               bufsize - tokenBegin, bufpos);
44             buffer = newbuffer;
45  
46             System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
47             System.arraycopy(bufline, 0, newbufline, bufsize - tokenBegin, bufpos);
48             bufline = newbufline;
49  
50             System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
51             System.arraycopy(bufcolumn, 0, newbufcolumn, bufsize - tokenBegin, bufpos);
52             bufcolumn = newbufcolumn;
53  
54             maxNextCharInd = (bufpos += (bufsize - tokenBegin));
55          }
56          else
57          {
58             System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
59             buffer = newbuffer;
60  
61             System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
62             bufline = newbufline;
63  
64             System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
65             bufcolumn = newbufcolumn;
66  
67             maxNextCharInd = (bufpos -= tokenBegin);
68          }
69       }
70       catch (Throwable t)
71       {
72          throw new Error(t.getMessage());
73       }
74  
75  
76       bufsize += 2048;
77       available = bufsize;
78       tokenBegin = 0;
79    }
80  
81    protected void FillBuff() throws java.io.IOException
82    {
83       if (maxNextCharInd == available)
84       {
85          if (available == bufsize)
86          {
87             if (tokenBegin > 2048)
88             {
89                bufpos = maxNextCharInd = 0;
90                available = tokenBegin;
91             }
92             else if (tokenBegin < 0)
93                bufpos = maxNextCharInd = 0;
94             else
95                ExpandBuff(false);
96          }
97          else if (available > tokenBegin)
98             available = bufsize;
99          else if ((tokenBegin - available) < 2048)
100            ExpandBuff(true);
101         else
102            available = tokenBegin;
103      }
104 
105      int i;
106      try {
107         if ((i = inputStream.read(buffer, maxNextCharInd,
108                                     available - maxNextCharInd)) == -1)
109         {
110            inputStream.close();
111            throw new java.io.IOException();
112         }
113         else
114            maxNextCharInd += i;
115         return;
116      }
117      catch(java.io.IOException e) {
118         --bufpos;
119         backup(0);
120         if (tokenBegin == -1)
121            tokenBegin = bufpos;
122         throw e;
123      }
124   }
125 
126   public char BeginToken() throws java.io.IOException
127   {
128      tokenBegin = -1;
129      char c = readChar();
130      tokenBegin = bufpos;
131 
132      return c;
133   }
134 
135   protected void UpdateLineColumn(char c)
136   {
137      column++;
138 
139      if (prevCharIsLF)
140      {
141         prevCharIsLF = false;
142         line += (column = 1);
143      }
144      else if (prevCharIsCR)
145      {
146         prevCharIsCR = false;
147         if (c == '\n')
148         {
149            prevCharIsLF = true;
150         }
151         else
152            line += (column = 1);
153      }
154 
155      switch (c)
156      {
157         case '\r' :
158            prevCharIsCR = true;
159            break;
160         case '\n' :
161            prevCharIsLF = true;
162            break;
163         case '\t' :
164            column--;
165            column += (8 - (column & 07));
166            break;
167         default :
168            break;
169      }
170 
171      bufline[bufpos] = line;
172      bufcolumn[bufpos] = column;
173   }
174 
175   public char readChar() throws java.io.IOException
176   {
177      if (inBuf > 0)
178      {
179         --inBuf;
180 
181         if (++bufpos == bufsize)
182            bufpos = 0;
183 
184         return buffer[bufpos];
185      }
186 
187      if (++bufpos >= maxNextCharInd)
188         FillBuff();
189 
190      char c = buffer[bufpos];
191 
192      UpdateLineColumn(c);
193      return (c);
194   }
195 
196   /**
197    * @deprecated
198    * @see #getEndColumn
199    */
200 
201   public int getColumn() {
202      return bufcolumn[bufpos];
203   }
204 
205   /**
206    * @deprecated
207    * @see #getEndLine
208    */
209 
210   public int getLine() {
211      return bufline[bufpos];
212   }
213 
214   public int getEndColumn() {
215      return bufcolumn[bufpos];
216   }
217 
218   public int getEndLine() {
219      return bufline[bufpos];
220   }
221 
222   public int getBeginColumn() {
223      return bufcolumn[tokenBegin];
224   }
225 
226   public int getBeginLine() {
227      return bufline[tokenBegin];
228   }
229 
230   public void backup(int amount) {
231 
232     inBuf += amount;
233     if ((bufpos -= amount) < 0)
234        bufpos += bufsize;
235   }
236 
237   public SimpleCharStream(java.io.Reader dstream, int startline,
238   int startcolumn, int buffersize)
239   {
240     inputStream = dstream;
241     line = startline;
242     column = startcolumn - 1;
243 
244     available = bufsize = buffersize;
245     buffer = new char[buffersize];
246     bufline = new int[buffersize];
247     bufcolumn = new int[buffersize];
248   }
249 
250   public SimpleCharStream(java.io.Reader dstream, int startline,
251                                                            int startcolumn)
252   {
253      this(dstream, startline, startcolumn, 4096);
254   }
255 
256   public SimpleCharStream(java.io.Reader dstream)
257   {
258      this(dstream, 1, 1, 4096);
259   }
260   public void ReInit(java.io.Reader dstream, int startline,
261   int startcolumn, int buffersize)
262   {
263     inputStream = dstream;
264     line = startline;
265     column = startcolumn - 1;
266 
267     if (buffer == null || buffersize != buffer.length)
268     {
269       available = bufsize = buffersize;
270       buffer = new char[buffersize];
271       bufline = new int[buffersize];
272       bufcolumn = new int[buffersize];
273     }
274     prevCharIsLF = prevCharIsCR = false;
275     tokenBegin = inBuf = maxNextCharInd = 0;
276     bufpos = -1;
277   }
278 
279   public void ReInit(java.io.Reader dstream, int startline,
280                                                            int startcolumn)
281   {
282      ReInit(dstream, startline, startcolumn, 4096);
283   }
284 
285   public void ReInit(java.io.Reader dstream)
286   {
287      ReInit(dstream, 1, 1, 4096);
288   }
289   public SimpleCharStream(java.io.InputStream dstream, int startline,
290   int startcolumn, int buffersize)
291   {
292      this(new java.io.InputStreamReader(dstream), startline, startcolumn, 4096);
293   }
294 
295   public SimpleCharStream(java.io.InputStream dstream, int startline,
296                                                            int startcolumn)
297   {
298      this(dstream, startline, startcolumn, 4096);
299   }
300 
301   public SimpleCharStream(java.io.InputStream dstream)
302   {
303      this(dstream, 1, 1, 4096);
304   }
305 
306   public void ReInit(java.io.InputStream dstream, int startline,
307                           int startcolumn, int buffersize)
308   {
309      ReInit(new java.io.InputStreamReader(dstream), startline, startcolumn, 4096);
310   }
311 
312   public void ReInit(java.io.InputStream dstream)
313   {
314      ReInit(dstream, 1, 1, 4096);
315   }
316   public void ReInit(java.io.InputStream dstream, int startline,
317                                                            int startcolumn)
318   {
319      ReInit(dstream, startline, startcolumn, 4096);
320   }
321   public String GetImage()
322   {
323      if (bufpos >= tokenBegin)
324         return new String(buffer, tokenBegin, bufpos - tokenBegin + 1);
325      else
326         return new String(buffer, tokenBegin, bufsize - tokenBegin) +
327                               new String(buffer, 0, bufpos + 1);
328   }
329 
330   public char[] GetSuffix(int len)
331   {
332      char[] ret = new char[len];
333 
334      if ((bufpos + 1) >= len)
335         System.arraycopy(buffer, bufpos - len + 1, ret, 0, len);
336      else
337      {
338         System.arraycopy(buffer, bufsize - (len - bufpos - 1), ret, 0,
339                                                           len - bufpos - 1);
340         System.arraycopy(buffer, 0, ret, len - bufpos - 1, bufpos + 1);
341      }
342 
343      return ret;
344   }
345 
346   public void Done()
347   {
348      buffer = null;
349      bufline = null;
350      bufcolumn = null;
351   }
352 
353   /**
354    * Method to adjust line and column numbers for the start of a token.<BR>
355    */
356   public void adjustBeginLineColumn(int newLine, int newCol)
357   {
358      int start = tokenBegin;
359      int len;
360 
361      if (bufpos >= tokenBegin)
362      {
363         len = bufpos - tokenBegin + inBuf + 1;
364      }
365      else
366      {
367         len = bufsize - tokenBegin + bufpos + 1 + inBuf;
368      }
369 
370      int i = 0, j = 0, k = 0;
371      int nextColDiff = 0, columnDiff = 0;
372 
373      while (i < len &&
374             bufline[j = start % bufsize] == bufline[k = ++start % bufsize])
375      {
376         bufline[j] = newLine;
377         nextColDiff = columnDiff + bufcolumn[k] - bufcolumn[j];
378         bufcolumn[j] = newCol + columnDiff;
379         columnDiff = nextColDiff;
380         i++;
381      }
382 
383      if (i < len)
384      {
385         bufline[j] = newLine++;
386         bufcolumn[j] = newCol + columnDiff;
387 
388         while (i++ < len)
389         {
390            if (bufline[j = start % bufsize] != bufline[++start % bufsize])
391               bufline[j] = newLine++;
392            else
393               bufline[j] = newLine;
394         }
395      }
396 
397      line = bufline[j];
398      column = bufcolumn[j];
399   }
400 
401 }