cd /tmp // get source git clone https://github.com/antlr/antlr4.git // check environment sudo apt-get update # get java java > /dev/null 2>&1 if [[ "$?" != "0" ]]; then sudo apt install -y openjdk-11-jre-headless; fi # get maven mvn > /dev/null 2>&1 if [[ "$?" != "0" ]]; then sudo apt install -y maven; fi // complie cd /tmp/antlr4 export MAVEN_OPTS="-Xmx1G"# don't forget this on linux mvn clean # must be separate, not part of install/compile mvn -DskipTests install