/**
* Resets this tokenizer for usage with another input stream.
* This method will clear all the internal state in the
* tokenizer as well as close the previous input stream. It
* is normally called in order to reuse a parser and
* tokenizer pair with multiple input streams, thereby
* avoiding the cost of re-analyzing the grammar structures.
*
* @param input the new input stream to read
*
* @see Parser#reset(Reader)
*
* @since 1.5
*/
public void Reset(TextReader input)
{
buffer.Dispose();
buffer = new ReaderBuffer(input);
previousToken = null;
lastMatch.Clear();
}
/**
* Finds the next token on the stream. This method will return
* null when end of file has been reached. It will return a
* parse exception if no token matched the input stream.
*
* @return the next token found, or
* null if end of file was encountered
*
* @throws ParseException if the input stream couldn't be read or
* parsed correctly
*/
private Token NextToken()
{
string str;
int line;
int column;
try {
lastMatch.Clear();
stringDfaMatcher.Match(buffer, lastMatch);
nfaMatcher.Match(buffer, lastMatch);
regExpMatcher.Match(buffer, lastMatch);
if (lastMatch.Length > 0)
{
line = buffer.LineNumber;
column = buffer.ColumnNumber;
str = buffer.Read(lastMatch.Length);
return(NewToken(lastMatch.Pattern, str, line, column));
}
else if (buffer.Peek(0) < 0)
{
return(null);
}
else
{
line = buffer.LineNumber;
column = buffer.ColumnNumber;
throw new ParseException(
ParseException.ErrorType.UNEXPECTED_CHAR,
buffer.Read(1),
line,
column);
}
} catch (IOException e) {
throw new ParseException(ParseException.ErrorType.IO,
e.Message,
-1,
-1);
}
}