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\#ifndef CHARSTREAM_H
\#define CHARSTREAM_H
\#include "JavaCC.h"

\#ifndef INITIAL_BUFFER_SIZE
\#define INITIAL_BUFFER_SIZE 4096
\#endif

#if NAMESPACE
namespace ${NAMESPACE_OPEN}
#fi

/**
 * This class describes a character stream that maintains line and
 * column number positions of the characters.  It also has the capability
 * to backup the stream to some extent.  An implementation of this
 * class is used in the TokenManager implementation generated by
 * JavaCCParser.
 *
 * All the methods except backup can be implemented in any fashion. backup
 * needs to be implemented correctly for the correct operation of the lexer.
 * Rest of the methods are all used to get information like line number,
 * column number and the string that constitutes a token and are not used
 * by the lexer. Hence their implementation won't affect the generated lexer's
 * operation.
 */


class CharStream {
 public:
  void setTabSize(int i) { tabSize = i; }
  int getTabSize(int i) { return tabSize; }
#if KEEP_LINE_COLUMN
  virtual int getColumn() { return trackLineColumn ? bufcolumn[bufpos] : -1; }
  virtual int getLine() { return trackLineColumn ? bufline[bufpos] : -1; }
  virtual int getEndColumn() { return trackLineColumn ? bufcolumn[bufpos] : -1; }
  virtual int getEndLine() { return trackLineColumn ? bufline[bufpos] : -1; }
  virtual int getBeginColumn() { return trackLineColumn ? bufcolumn[tokenBegin] : -1; }
  virtual int getBeginLine() { return trackLineColumn ? bufline[tokenBegin] : -1; }
#else
  virtual int getColumn() { return -1; }
  virtual int getLine() { return -1; }
  virtual int getEndColumn() { return -1; }
  virtual int getEndLine() { return -1; }
  virtual int getBeginColumn() { return -1; }
  virtual int getBeginLine() { return -1; }
#fi

  virtual bool getTrackLineColumn() { return trackLineColumn; }
  virtual void setTrackLineColumn(bool val) { trackLineColumn = val; }

/**
 * Backs up the input stream by amount steps. Lexer calls this method if it
 * had already read some characters, but could not use them to match a
 * (longer) token. So, they will be used again as the prefix of the next
 * token and it is the implemetation's responsibility to do this right.
 */
virtual inline void backup(int amount) {
  inBuf += amount;
  bufpos -= amount;
  if (bufpos < 0) {
    bufpos += bufsize;
  }
}

/**
 * Returns the next character that marks the beginning of the next token.
 * All characters must remain in the buffer between two successive calls
 * to this method to implement backup correctly.
 */
virtual inline JAVACC_CHAR_TYPE BeginToken() {
  tokenBegin = -1;
  JAVACC_CHAR_TYPE c = readChar();
  tokenBegin = bufpos;
  return c;
}


/**
 * Returns the next character from the selected input.  The method
 * of selecting the input is the responsibility of the class
 * implementing this class.
 */
virtual inline JAVACC_CHAR_TYPE readChar() {
  if (inBuf > 0) {
    --inBuf;
    ++bufpos;
    if (bufpos == bufsize) {
      bufpos = 0;
    }

    return buffer[bufpos];
  }

  ++bufpos;
  if (bufpos >= maxNextCharInd) {
    FillBuff();
  }

  JAVACC_CHAR_TYPE c = buffer[bufpos];

#if KEEP_LINE_COLUMN
  if (trackLineColumn) {
    UpdateLineColumn(c);
  }
#fi

  return c;
}


  virtual void ExpandBuff(bool wrapAround);
  virtual void FillBuff();

  /**
   * Returns a string made up of characters from the marked token beginning
   * to the current buffer position. Implementations can return
   * anything that they want to. For example, for efficiency, one might decide
   * to just return NULL, which is a valid implementation.
   */
  virtual JAVACC_STRING_TYPE GetImage() {
    if (bufpos >= tokenBegin)
      return JAVACC_STRING_TYPE(buffer + tokenBegin, bufpos - tokenBegin + 1);
    else
      return JAVACC_STRING_TYPE(buffer + tokenBegin, bufsize - tokenBegin)
             .append(buffer, bufpos + 1);
  }

  /**
   * Returns an array of characters that make up the suffix of length 'len' for
   * the currently matched token. This is used to build up the matched string
   * for use in actions in the case of MORE. A simple and inefficient
   * implementation of this is as follows :
   */
  virtual JAVACC_STRING_TYPE GetSuffix(int len) {
    if ((bufpos + 1) >= len) {
      return JAVACC_STRING_TYPE(buffer + bufpos - len + 1, len);
    }
    return JAVACC_STRING_TYPE(buffer + bufsize - (len - bufpos - 1), len - bufpos - 1)
           .append(buffer, bufpos + 1);
  }

  /**
   * The lexer calls this function to indicate that it is done with the stream
   * and hence implementations can free any resources held by this class.
   */
  virtual void DeleteBuffers();

  virtual ~CharStream() {
    if (deleteStream) {
     delete inputStream;
    }
    DeleteBuffers();
  }

  bool endOfInput() {
    return inBuf == 0 && bufpos + 1 >= maxNextCharInd &&
           inputStream->endOfInput();
  }

  CharStream(const JAVACC_CHAR_TYPE *buf, int sz, int startline,
                      int startcolumn, int buffersize) :
    bufline(NULL), bufcolumn(NULL), inputStream(NULL), deleteStream(false),
    buffer(NULL), bufpos(0), bufsize(0), tokenBegin(0), column(0), line(0),
    prevCharIsCR (false), prevCharIsLF (false), available(0), maxNextCharInd(0),
    inBuf(0),tabSize(1), trackLineColumn(true) {
    ReInit(JAVACC_STRING_TYPE(buf, sz), startline, startcolumn, buffersize);
  }

  CharStream(const JAVACC_CHAR_TYPE *buf, int sz, int startline, int startcolumn) :
    bufline(NULL), bufcolumn(NULL), inputStream(NULL), deleteStream(false),
    buffer(NULL), bufpos(0), bufsize(0), tokenBegin(0), column(0), line(0),
    prevCharIsCR (false), prevCharIsLF (false), available(0), maxNextCharInd(0),
    inBuf(0),tabSize(1), trackLineColumn(true) {
    ReInit(JAVACC_STRING_TYPE(buf, sz), startline, startcolumn, INITIAL_BUFFER_SIZE);
  }

  CharStream(const JAVACC_STRING_TYPE& str, int startline,
                      int startcolumn, int buffersize) :
    bufline(NULL), bufcolumn(NULL), inputStream(NULL), deleteStream(false),
    buffer(NULL), bufpos(0), bufsize(0), tokenBegin(0), column(0), line(0),
    prevCharIsCR (false), prevCharIsLF (false), available(0), maxNextCharInd(0),
    inBuf(0),tabSize(1), trackLineColumn(true) {
    ReInit(str, startline, startcolumn, buffersize);
  }

  CharStream(const JAVACC_STRING_TYPE& str, int startline, int startcolumn) :
    bufline(NULL), bufcolumn(NULL), inputStream(NULL), deleteStream(false),
    buffer(NULL), bufpos(0), bufsize(0), tokenBegin(0), column(0), line(0),
    prevCharIsCR (false), prevCharIsLF (false), available(0), maxNextCharInd(0),
    inBuf(0) ,tabSize(1), trackLineColumn(true){
    ReInit(str, startline, startcolumn, INITIAL_BUFFER_SIZE);
  }

  CharStream(ReaderStream *input_stream, int startline,
             int startcolumn, int buffersize) :
    bufline(NULL), bufcolumn(NULL), inputStream(NULL), deleteStream(false),
    buffer(NULL), bufpos(0), bufsize(0), tokenBegin(0), column(0), line(0),
    prevCharIsCR (false), prevCharIsLF (false), available(0), maxNextCharInd(0),
    inBuf(0),tabSize(1), trackLineColumn(true) {
    ReInit(input_stream, startline, startcolumn, INITIAL_BUFFER_SIZE);
  }

  CharStream(ReaderStream *input_stream, int startline, int startcolumn) :
    bufline(NULL), bufcolumn(NULL), inputStream(NULL), deleteStream(false),
    buffer(NULL), bufpos(0), bufsize(0), tokenBegin(0), column(0), line(0),
    prevCharIsCR (false), prevCharIsLF (false), available(0), maxNextCharInd(0),
    inBuf(0),tabSize(1), trackLineColumn(true) {
    ReInit(input_stream, startline, startcolumn, INITIAL_BUFFER_SIZE);
  }

  CharStream(ReaderStream *input_stream) :
    bufline(NULL), bufcolumn(NULL), inputStream(NULL), deleteStream(false),
    buffer(NULL), bufpos(0), bufsize(0), tokenBegin(0), column(0), line(0),
    prevCharIsCR (false), prevCharIsLF (false), available(0), maxNextCharInd(0),
    inBuf(0),tabSize(1), trackLineColumn(true) {
    ReInit(input_stream, 1, 1, INITIAL_BUFFER_SIZE);
  }

  virtual void ReInit(ReaderStream *input_stream, int startline, int startcolumn,
                      int buffersize);

  virtual void ReInit(ReaderStream *input_stream, int startline,
                      int startcolumn) {
    ReInit(input_stream, startline, startcolumn, INITIAL_BUFFER_SIZE);
  }

  virtual void ReInit(ReaderStream *input_stream) {
    ReInit(input_stream, 1, 1, INITIAL_BUFFER_SIZE);
  }

  virtual void ReInit(const JAVACC_STRING_TYPE& str, int startline,
                      int startcolumn, int buffersize);

  virtual void ReInit(const JAVACC_STRING_TYPE& str, int startline,
                      int startcolumn) {
    ReInit(str, startline, startcolumn, INITIAL_BUFFER_SIZE);
  }

  virtual void adjustBeginLineColumn(int newLine, int newCol);

 protected:
  virtual void UpdateLineColumn(JAVACC_CHAR_TYPE c);

  int *bufline;
  int *bufcolumn;
  ReaderStream *inputStream;
  bool deleteStream;
  JAVACC_CHAR_TYPE * buffer;
  int bufpos;
  int bufsize;
  int tokenBegin;
  int column;
  int line;
  bool prevCharIsCR ;
  bool prevCharIsLF ;
  int available;
  int maxNextCharInd;
  int inBuf ;
  int tabSize ;
  bool trackLineColumn;
};

#if NAMESPACE
${NAMESPACE_CLOSE}
#fi
\#endif




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