// generate parser code from grammar Exp.g 
java -cp antlr-4.13.1-complete.jar org.antlr.v4.Tool Exp.g

// compile parser code
javac -cp .:antlr-4.13.1-complete.jar *.java

// call parser on stdin, to display parse tree in gui
java -cp .:antlr-4.13.1-complete.jar org.antlr.v4.gui.TestRig Exp eval -gui

// call parser on stdin, to display parse tree in console
java -cp .:antlr-4.13.1-complete.jar org.antlr.v4.gui.TestRig Exp eval

// call arithmetic expression evaluator on test in file test1.txt
java -cp .:antlr-4.13.1-complete.jar Main test1.txt