sudo update-alternatives --install /usr/bin/java java /opt/jdk1.6.0_45/bin/java 1 sudo update-alternatives --install /usr/bin/javac javac /opt/jdk1.6.0_45/bin/javac 1 sudo update-alternatives --config java
If you are stuck on a Linux terminal without a GUI, you can use wget with the appropriate cookies. However, due to Oracle’s authentication requirements, the simplest approach is to obtain a direct download link from the Oracle website (copy link address) and use it with wget --no-cookies --header . Download Sun Jdk 6 For Linux