How to use

setListener

method

in

ca.uhn.hl7v2.parser.GenericParser

 // the ANTLR grammar
File f = new File("src/test/ressources/Java.g4");
// plug the ANTLR grammar in 
GenericParser gp = new GenericParser(f, "Java");
// load the file that we'd like to parse into a String variable
String s = FileUtils.loadFileContent("src/test/ressources/HelloWorld.java");
// this listener will create an AST from the java file    
gp.setListener(new DefaultTreeListener());
// compile Parser/Lexer
gp.compile();
ParserRuleContext ctx = ctx = gp.parse(s);
// get access to AST
Ast ast = dlist.getAst();
// print AST in dot format
System.out.println(ast.toDot());