Build a Droid - Need help with energyTransfer method

I am pretty stumped on how to transfer one objects batteryLevel to the others. Can somebody please explain?

Here’s a thread about it in stack overflow

I’m in the same boat. I don’t understand what to put inside the energyTransfer() method.
I looked at the link from ruby5230943909
but the answers seemed a bit advanced. I don’t believe we’ve learnt about 'this. ’ yet so I think there must be a different way.
Anyone have any tips?

This is what I did

This is the method

   public void energyTransfer(int power, Droid transferTo){  
     batteryLevel -= power;
    transferTo.batteryLevel += power;

Then I called it by typing

c3po.energyTransfer(20, codey);

Does this help?