Adder.jj

options {
		STATIC = false;
		DEBUG_PARSER = true;
		UNICODE_INPUT = true;
		JDK_VERSION = "1.6";
}

PARSER_BEGIN(Adder)
		import java.io.*;

class Adder {
		static public void main(String[] args) {
				for (String arg : args){
						try {
								System.out.println(evaluate(arg));
						}
						catch (ParseException ex){
								System.err.println(ex.getMessage());
						}
				}
		}
		static public long evaluate(String src) throws ParseException {
				Reader reader = new StringReader(src);
				return new Adder(reader).expr();
		} 
}
PARSER_END(Adder)

SKIP: {<[" ","\t","\r","\n"]>}

TOKEN: {
		<INTEGER: (["0"-"9"])+>
}

long expr():
{
		Token x,y;
}
{
		x=<INTEGER> "+" y=<INTEGER> <EOF>
		{
				return Long.parseLong(x.image) + Long.parseLong(y.image);
		}
}