has no installation candidate

qwe@qwe-VirtualBox:~$ sudo apt-get install sun-java6-jdk
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package sun-java6-jdk is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'sun-java6-jdk' has no installation candidate

You are about to add the following PPA to your system:
Oracle Java (JDK) Installer (automatically downloads and installs Oracle JDK6 / JDK7 / JDK8). There are no actual Java files in this PPA.