cd /usr/local/lib
sudo curl -O https://www.antlr.org/download/antlr-4.8-complete.jar
vim ~/.bash_profile
# add & save
#export CLASSPATH=".:/usr/local/lib/antlr-4.8-complete.jar:$CLASSPATH"
#alias antlr4='java -jar /usr/local/lib/antlr-4.8-complete.jar'
#alias grun='java org.antlr.v4.gui.TestRig'
source ~/.bash_profile