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Java

Posted by Rumbidzai Rutendo Nhopi Nyikadzinashe
Rumbidzai Rutendo Nhopi Nyikadzinashe
1,482 Points

List

Fill in the bkank to declare the rocks variable as a list that contain rocks

1 Answer

Tonnie Fanadez
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Tonnie Fanadez
UX Design Techdegree Graduate 22,796 Points
Tonnie Fanadez
.a{fill-rule:evenodd;}techdegree seal-36
Tonnie Fanadez
UX Design Techdegree Graduate 22,796 Points

Hi Rumbidzai Rutendo Nhopi Nyikadzinashe - quite a name there.

List represents an ordered sequence of objects; since List is an interface, you need to instantiate a concrete implementation of the interface in order to use it. The most common implementation is ArrayList which I have used below. Other implementations of List Interface are LinkedList and Vector

List<Rock> rocks = new ArrayList<>();

So you need to declare a List of type Rock (put this inside the diamond brackets) - I have called mine just rocks and then instantiated the list to a new ArrayList. I have left the diamond brackets on the Right side empty because the compiler will infer it as Rock type so you don't have to worry or specify the type on the Right side.