Saturday Mac riddles 69

Here are this weekend’s riddles to entertain you through whatever you’re now allowed to do.

1: Elsewhere I stop the flow, but if you don’t connect me you’ve no power, external disks, or displays. What am I?

2: Half asleep, or a quick doze to invigorate before cracking on.

3: I should have been Peter’s Java for kids, but got hijacked by what’s after next to form the basis for almost everything. What am I?

I will post the answers first thing on Monday morning.

Please don’t post your answers as comments here: it spoils it for others.