Beginner problem with .gitignore

Hello.

I have a file called TitleAreaDialog.java in the folder
my_path\org.eclipse.jface\src\org\eclipse\jface\dialogs

.git and .gitignore is in the my_path\ folder (using Git Cygwin on Windows).

Now I everything is ignored from org.eclipse.jface, but not that 
TitleAreaDialog.java

So I specified the following in .gitignore:
/org.eclipse.*
!TitleAreaDialog.java

I also tried it with:
!Title*, 
!/org.eclipse.jface/src/org/eclipse/jface/dialogs/TitleAreaDialog.java

but the TitleAreaDialog is always ignored as well.

What do I have to do to not ignore this file specifically?

Best regards,
Kai