And I still can't find what I am looking for I told ya, a more idiotic way. That means an actual guide how to use the generated code, how to edit the code correctly so it does what it's intended to do. Did you check out the GitHub link I posted? Then you might see what the generated code looks like. The lexer and parser Java source code files contain no usable JavaDoc, the interface classes JSONVisitor and JSONListener do contain quite more helpful JavaDoc, but no information on what should actually go inside. And the implementations JSONBaseListener and JSONBaseVisitor contain nothing. Listener is empty and Visitor contains default visitChildren() method, which I'm not quite certain what it does and if this is actually what it should do... Well, frankly to say, I cannot tell at all what that default method actually does. The listener contains no code in implemented methods at all, so this is truly wrong. But I don't know how to fix it. The Definitive ANTLR4 takes it more broadly, it's not actually a guide for the use of ANTLR, only general explanation, so I am quite glad I didn't have to give my money for that. There was a section about parsing JSON, but it didn't contain the explanation of the generated methods (like the general broad explanation didn't quite explain generated classes), it moved straight to the testing of generated and fully implemented parser, which I cannot see Can't I really find anything that would tell me "put this there, remove that, change this"? This is an idiotic way of explanation that I am looking for. This is what we in Czech call "shovel method" of explanation...