Eclipse Template Proposals (aka auto completion) not working

Question

recently the proposals ( Ctrl + Space ) for Eclipse/Java stopped working, as suggested in the wiki I looked at the Preferences of Content Assist for Java , but all options are checked and still not working, any idea?

EDIT: One error is shown while trying to display proposals: Project facet grails.app has not been defined. It is used in plugin com.springsource.sts.server.tc.core. Project facet grails.app has not been defined. It is used in plugin com.springsource.sts.server.tc.core.

Answer 1

Somehow the references to the JDK where broken, so no completions could be made!

UPDATE: Solved by going to Window -> Preferences -> Installed JREs and changing the JDK folder to the right one.