install openjdk8 debian code example
Example: install openjdk 8 debian 10
wget -qO - https://adoptopenjdk.jfrog.io/adoptopenjdk/api/gpg/key/public | sudo apt-key add -
sudo add-apt-repository --yes https://adoptopenjdk.jfrog.io/adoptopenjdk/deb/
sudo apt-get update && sudo apt-get install adoptopenjdk-8-hotspot