1   /* Generated By:JavaCC: Do not edit this line. ASCII_CharStream.java Version 0.7pre6 */
2   package gate.jape.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 final class ASCII_CharStream
10  {
11    public static final boolean staticFlag = false;
12    int bufsize;
13    int available;
14    int tokenBegin;
15    public int bufpos = -1;
16    private int bufline[];
17    private int bufcolumn[];
18  
19    private int column = 0;
20    private int line = 1;
21  
22    private boolean prevCharIsCR = false;
23    private boolean prevCharIsLF = false;
24  
25    private java.io.Reader inputStream;
26  
27    private char[] buffer;
28    private int maxNextCharInd = 0;
29    private int inBuf = 0;
30  
31    private final 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    private final 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 final char BeginToken() throws java.io.IOException
127   {
128      tokenBegin = -1;
129      char c = readChar();
130      tokenBegin = bufpos;
131 
132      return c;
133   }
134 
135   private final 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 final char readChar() throws java.io.IOException
176   {
177      if (inBuf > 0)
178      {
179         --inBuf;
180         return (char)((char)0xff & buffer[(bufpos == bufsize - 1) ? (bufpos = 0) : ++bufpos]);
181      }
182 
183      if (++bufpos >= maxNextCharInd)
184         FillBuff();
185 
186      char c = (char)((char)0xff & buffer[bufpos]);
187 
188      UpdateLineColumn(c);
189      return (c);
190   }
191 
192   /**
193    * @deprecated 
194    * @see #getEndColumn
195    */
196 
197   public final int getColumn() {
198      return bufcolumn[bufpos];
199   }
200 
201   /**
202    * @deprecated 
203    * @see #getEndLine
204    */
205 
206   public final int getLine() {
207      return bufline[bufpos];
208   }
209 
210   public final int getEndColumn() {
211      return bufcolumn[bufpos];
212   }
213 
214   public final int getEndLine() {
215      return bufline[bufpos];
216   }
217 
218   public final int getBeginColumn() {
219      return bufcolumn[tokenBegin];
220   }
221 
222   public final int getBeginLine() {
223      return bufline[tokenBegin];
224   }
225 
226   public final void backup(int amount) {
227 
228     inBuf += amount;
229     if ((bufpos -= amount) < 0)
230        bufpos += bufsize;
231   }
232 
233   public ASCII_CharStream(java.io.Reader dstream, int startline,
234   int startcolumn, int buffersize)
235   {
236     inputStream = dstream;
237     line = startline;
238     column = startcolumn - 1;
239 
240     available = bufsize = buffersize;
241     buffer = new char[buffersize];
242     bufline = new int[buffersize];
243     bufcolumn = new int[buffersize];
244   }
245 
246   public ASCII_CharStream(java.io.Reader dstream, int startline,
247                                                            int startcolumn)
248   {
249      this(dstream, startline, startcolumn, 4096);
250   }
251   public void ReInit(java.io.Reader dstream, int startline,
252   int startcolumn, int buffersize)
253   {
254     inputStream = dstream;
255     line = startline;
256     column = startcolumn - 1;
257 
258     if (buffer == null || buffersize != buffer.length)
259     {
260       available = bufsize = buffersize;
261       buffer = new char[buffersize];
262       bufline = new int[buffersize];
263       bufcolumn = new int[buffersize];
264     }
265     prevCharIsLF = prevCharIsCR = false;
266     tokenBegin = inBuf = maxNextCharInd = 0;
267     bufpos = -1;
268   }
269 
270   public void ReInit(java.io.Reader dstream, int startline,
271                                                            int startcolumn)
272   {
273      ReInit(dstream, startline, startcolumn, 4096);
274   }
275   public ASCII_CharStream(java.io.InputStream dstream, int startline,
276   int startcolumn, int buffersize)
277   {
278      this(new java.io.InputStreamReader(dstream), startline, startcolumn, 4096);
279   }
280 
281   public ASCII_CharStream(java.io.InputStream dstream, int startline,
282                                                            int startcolumn)
283   {
284      this(dstream, startline, startcolumn, 4096);
285   }
286 
287   public void ReInit(java.io.InputStream dstream, int startline,
288   int startcolumn, int buffersize)
289   {
290      ReInit(new java.io.InputStreamReader(dstream), startline, startcolumn, 4096);
291   }
292   public void ReInit(java.io.InputStream dstream, int startline,
293                                                            int startcolumn)
294   {
295      ReInit(dstream, startline, startcolumn, 4096);
296   }
297   public final String GetImage()
298   {
299      if (bufpos >= tokenBegin)
300         return new String(buffer, tokenBegin, bufpos - tokenBegin + 1);
301      else
302         return new String(buffer, tokenBegin, bufsize - tokenBegin) +
303                               new String(buffer, 0, bufpos + 1);
304   }
305 
306   public final char[] GetSuffix(int len)
307   {
308      char[] ret = new char[len];
309 
310      if ((bufpos + 1) >= len)
311         System.arraycopy(buffer, bufpos - len + 1, ret, 0, len);
312      else
313      {
314         System.arraycopy(buffer, bufsize - (len - bufpos - 1), ret, 0,
315                                                           len - bufpos - 1);
316         System.arraycopy(buffer, 0, ret, len - bufpos - 1, bufpos + 1);
317      }
318 
319      return ret;
320   }
321 
322   public void Done()
323   {
324      buffer = null;
325      bufline = null;
326      bufcolumn = null;
327   }
328 
329   /**
330    * Method to adjust line and column numbers for the start of a token.<BR>
331    */
332   public void adjustBeginLineColumn(int newLine, int newCol)
333   {
334      int start = tokenBegin;
335      int len;
336 
337      if (bufpos >= tokenBegin)
338      {
339         len = bufpos - tokenBegin + inBuf + 1;
340      }
341      else
342      {
343         len = bufsize - tokenBegin + bufpos + 1 + inBuf;
344      }
345 
346      int i = 0, j = 0, k = 0;
347      int nextColDiff = 0, columnDiff = 0;
348 
349      while (i < len &&
350             bufline[j = start % bufsize] == bufline[k = ++start % bufsize])
351      {
352         bufline[j] = newLine;
353         nextColDiff = columnDiff + bufcolumn[k] - bufcolumn[j];
354         bufcolumn[j] = newCol + columnDiff;
355         columnDiff = nextColDiff;
356         i++;
357      } 
358 
359      if (i < len)
360      {
361         bufline[j] = newLine++;
362         bufcolumn[j] = newCol + columnDiff;
363 
364         while (i++ < len)
365         {
366            if (bufline[j = start % bufsize] != bufline[++start % bufsize])
367               bufline[j] = newLine++;
368            else
369               bufline[j] = newLine;
370         }
371      }
372 
373      line = bufline[j];
374      column = bufcolumn[j];
375   }
376 
377 }
378