Ok – apologies then, I didn’t realise you had mastered the previous assignment.
What I would say is think about what you want the software to do from one program loop to the next – i.e.
Program loop 1 – draw a circle of radius r, in position x1, y1
Program loop 2 – delete circle of radius r in position x1, y1, draw circle of radius r in position x2, y2
Program loop 3, delete circle of radius r….. and so on.
Then think about how you might use different types of loops (for, while etc) to achieve what you want. Remember that coding is just a means to an end, you need to understand exactly what you want it to do before you start trying to write your code. Write it down in pseudo code or even a flow chart before you start, and then you have your code ‘requirement’ in front of you.
Java isn’t what I use day to day, so I can’t help you with the syntax, but there are plenty of resources about for that.