Question: How do I Install Java on Ubuntu or Debian OS? Answer: If Java is not installed, you’ll get the following error message when you do java -version. # java -version The program 'java' can be found in the following packages: * gij-4.3 * java-gcj-compat-headless * openjdk-6-jre-headless * cacao * gij-4.2 * jamvm * kaffe [...]