[antlr-interest] Bad exception handling ?

[julius_siska]

Hi,

I have following problem. I have grammar file with tokens AK, KI, EC 
and ZD. One of parsing rules is:
   (AK)? (KI)? EC (ZD)?
Parsed input stream contains just tokens:
   AK ZD    
(obviously missing EC token)

Relevant part of generated Java parser code to my grammar is as 
follows (for brevity I ommit unnecessary curly braces):

      switch ( LA(1)) {
	case AK:
	        match(AK);
	        break;
	case KI:
	case EC:
		break;
	default:
		throw new NoViableAltException(LT(1), getFilename());
      }
      switch ( LA(1)) {
	case KI:
		match(KI);
		break;
	case EC:
		break;
	default:
!!!		throw new NoViableAltException(LT(1), getFilename());
      }
      match(EC);
   
During parsing, is in line marked by !!! thrown NoViableAltException, 
because in the stream is not the EC token present. 
But the parser just print error message line:xxx:y: unexpected token 
ZD. Thrown exception is caught somewehre inside ANTLR, but I would 
need to have it thrown outside to know that something is wrong in my 
program. I think this exception should be thrown from parser.file() 
method.

Can somebody help me, how to get this exception out of ANTLR and into 
my program where I can handle it and reject such input stream ?

Thanks in advance,
   Julius Siska


 

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