That looks like a mistake - the Rentals (Java classes conventionally begin with an upper case letter) class should have an instance of Client, not just a clientID (ie like the 3 DVD members).
JamesCherrill
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Forget about relational stuff. This is Object Oriented. You don't create a relationship using IDs, you have variables that contain direct to the objects themselves. Don't worry if this doesn't quite compute yet - it's a concept that sometimes takes a little time to grok, especially if you've just come from doing relational databases.
You get an instance of Client somehow, you get an instance of DVD somehow. You create an instance of Rental that has the Client and the DVD as its instance variables. The ID's play no part in that.
JamesCherrill
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