Re: [jflex-users] problem handling the character hex FF

[Gerwin K. <ger...@ni...>]

Hi Ulf,

you need to use %16bit or %unicode instead of %8bit.

Java represents characters internally as unicode and 0xFF is apparently mapped 
to 711 in the character encoding that is used.

Cheers,
Gerwin

Ulf Dittmer wrote:
> Hello-
> 
> I'm trying to handle a file that contains the character hex FF, but that results in an exception: 
> Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 711
>         at JFlex_problem.yylex(JFlex_problem.java:503)
>         at JFlex_problem.main(JFlex_problem.java:237)
> 
> 711 is the value of the zzInput variable, which is used as an index into an array of length 256.
> 
> I thought declaring the parser as "8bit" should be sufficient to handle just about everything; am I missing something? I'm appending a minimal jflex file that exhibits the problem below. I'd be grateful on any clues on how to handle that character.
> 
> Thanks in advance,
> Ulf
> 
> 
> 
> import java.io.*;
> 
> %%
> 
> %public
> %class JFlex_problem
> %8bit
> %int
> %apiprivate
> 
> %{
> 	public JFlex_problem() { }
> 
> 	public static void main (String args[]) throws Exception {
> 		if (args == null) {
> 			System.err.println("usage: java JFlex_problem file");
> 			System.exit(1);
> 		}
> 		JFlex_problem self = new JFlex_problem();
> 		self.zzReader = new FileReader(args[0]);
> 		while ( !self.zzAtEOF ) self.yylex();
> 	}
> 
> %}
> 
> %%
> 
> <YYINITIAL> {
> 	. {
> 		System.out.println("read char: "+(int)yytext().charAt(0));
> 	}
> }
> 
> .|\n {
> 	/* ignore every character that's not recognizably part of a command */
> 	System.out.println("ignoring char: "+(int)yytext().charAt(0));
> }
> 
> 
> 
>       
> 
> ------------------------------------------------------------------------------
> Enter the BlackBerry Developer Challenge  
> This is your chance to win up to $100,000 in prizes! For a limited time, 
> vendors submitting new applications to BlackBerry App World(TM) will have
> the opportunity to enter the BlackBerry Developer Challenge. See full prize  
> details at: http://p.sf.net/sfu/Challenge
> --
> jflex-users mailing list
> https://lists.sourceforge.net/lists/listinfo/jflex-users