Page Comparison

import org.antlr.runtime.*;
import org.antlr.runtime.tree.*;

public class Test {
    public static void main(String[] args) throws Exception {
        ANTLRInputStream input = new ANTLRInputStream(System.in);
        ExprLexer lexer = new ExprLexer(input);
        CommonTokenStream tokens = new CommonTokenStream(lexer);
        ExprParser parser = new ExprParser(tokens);
        ExprParser.prog_return r = parser.prog();

        // walk resulting tree
        CommonTree t = (CommonTree)r.getTree();
        CommonTreeNodeStream nodes = new CommonTreeNodeStream(t);
        EvalTreeParserEval walker = new EvalTreeParserEval(nodes);
        walker.prog();
    }
}