Java .bak files in Project view

I have an Android project that contains many .java files.  I noticed that there are also several .bak files that are created and shown in the Project view.  Is there a way to hide these files from view?  Also, is there a way to exclude them from being included when searching for text, etc.

I have looked in the forums but I could not find a topic like this so I'm sorry if this has already been asked.

Thank you,

Steve