antlr # MyLanguage.g grammar MyLanguage; startRule: 'Hello' ID EOF; import org.antlr.v4.runtime.*; import org.antlr.v4.runtime.tree.*; import org.stringtemplate.v4.*; public class MyLanguageExample { public static void main(String[] args) { String input = "Hello John"; ANTLRInputStream inputStream = new ANTLRInputStream(input); MyLanguageLexer lexer = new MyLanguageLexer(inputStream); CommonTokenStream tokenStream = new CommonTokenStream(lexer); MyLanguageParser parser = new MyLanguageParser(tokenStream); ParseTree tree = parser.startRule(); ST template = new ST("Hello, <name>!"); template.add("name", tree.getChild(1).getText()); System.out.println(template.render()); } }