How to remove certain classes from autocompletion in Eclipse

How to make Eclipse ignore some classes or packages when invoking autocompletion?

I have two classes with identical class name and different package in my project's classpath: bad.package.MyClass and good.package.MyClass.

When I type class name and type ctrl-space, Eclipse will suggest importing those two classes. The problem is that it is a开发者_如何学Golways suggesting the wrong one first. The wrong one happens to be alphabetically first.

How can I fix this? Is there somewhere a setting "do not try to autocomplete to class X"?

You can set up ignored classes under

Preferences > Java > Appearance > Type Filters