Getting started

How to I install and run a simple grammar?

See Getting Started with ANTLR v4.

Why does my parser test program hang?

Your test program is likely not hanging but simply waiting for you to type some input for standard input. Don't forget that you need to type the end of file character, generally on a line by itself, at the end of the input. On a Mac or Linux machine it is ctrl-D, as gawd intended, or ctrl-Z on a Windows machine.

See Getting Started with ANTLR v4.