Fixing Java Eclipse AutoComplete Intellisense

Apparently a lot of things can mess up the autocomplete intellisense in eclipse, but the one that bit me was accidentally opening the java file in the text editor within eclipse instead of the java editor. Once you do that it gets stuck on that option. To fix it go to the navigator, find the java source code file you want to use right-click and say open with and flip from text editor to java editor. All fixed!