Display function prototype on bracket opening

I'm learning java using NetBeans. I want the IDE to display a function prototype after I type '(' so tha开发者_StackOverflow中文版t if I forget some parameters I do not need to erase the function name and '.' and type '.' again in order to see all the functions of that class. How can I turn it on?

It you press Ctrl+Space the pop-up list of protypes will be displayed for you.

It is probably already on. Have you just tried CTRL+Space ?