Yylex4_7

import java.io.*;
class Main{
	public static void main(String args[]) throws IOException	{
		Yylex4_7 lex=new Yylex4_7(System.in);
		Token token=lex.yylex();
		while(token.text!=null)	{
			token=lex.yylex();
		}
	}
}
class Token	{
	String text;
	Token(String t){text=t;}
}
%%
%public
%class Yylex4_7
%type void
digit=[0-9]
letter=[a-zA-Z]
special = [!@#$%^&*()_+]

whitespace = [ \t\n]
%type Token
%eofval{
	return new Token(null);
%eofval}
%%
\/\*({digit}|{letter}|{special})*\*\/ 
{  
 System.out.print("<A valid Identifier: " + yytext() + ">");} 
 {whitespace}+  
 { 
  /*Skip white spaces*/ 
 }