Eclipse keyboard shortcut to indent source code to the left?
In my copy, Shift + Tab does this, as long as I have a code selection, and am in a code window.
Ctrl + I (indentation). See at http://www.rossenstoyanchev.org/write/prog/eclipse/eclipse3.html Search for Indentation.
You can use Ctrl + Shift + F which will run your formatter on the file and fix indentations along the way also.