I installed jdk 7 but minecraft didnt work. I tried uninstalling it in many ways but it was still on the machine and minecraft still didnt work. Does anynone know how to fix this? My ubuntu version is 12.04 LTS. Ive searched the internet and i cant find anything that works. whenever i try something new java 7 still appears in dash home and minecraft still gets black screen. after trying a few new things minecraft wont even open i tried sudo apt-get purge, apt-get remove and a lot of other commands.i cant quite remember the ppa but i think it was http://www.launchpad.net/webupd8/java7 that might not be correct but thats what i remember. i also tried to mod minecraft by deleting meta-inf and adding minecraft forge.