This is how you should Install multiple Java Versions On Linux Mint 20 using alternatives. Install default java version apt install default-jdk Install java 8 apt install openjdk-8-jdk View isntalled java versions update-java-alternatives --list My out put is two java versions as following java-1.11.0-openjdk-amd64 1111 /usr/lib/jvm/java-1.11.0-openjdk-amd64 java-1.8.0-openjdk-amd64 1081 /usr/lib/jvm/java-1.8.0-openjdk-amd64 Check current version java -version mine is java 11 Change java version update-alternatives --config java and select the required version number All set now can use multiple java versions and switch them easily. Ref: https://techviewleo.com/install-java-openjdk-on-linux-mint/