Install antlr4 by entering the following commands in the terminal:
sudo apt update sudo apt install antlr4
ANTLR Parser Generator
ANTLR (ANother Tool for Language Recognition) is a powerful parser generator for reading, processing, executing, or translating structured text or binary files. It's widely used to build languages, tools, and frameworks. From a grammar, ANTLR generates a parser that can build and walk parse trees.