Compiling sample ANTRL4 output

There was 2 problems. One was the file has to be named “Hello.g4” not “hello.g4” because the grammar is specified as Hello. The second was the classpath, it requires the path and name of the jar file, as well as the current directory. The following command worked; javac -classpath .;C:\JavaLib\antlr-4.5-complete.jar *.java