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I can type 

ArrayList<T> l = new ArrayListList<T>();

and 

List<T> l = new ArrayList<T>();

but Java does not allow me to use 

List<T> l = new List<T>();

Why?

Pshemo
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sammy333
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    Because `List` is an interface – ಠ_ಠ Jul 21 '14 at 19:19
  • `List` is an interface. You cannot instantiate an interface. `ArrayList` is a class, which is an implementation of `List`. Classes can be instantiated. – forgivenson Jul 21 '14 at 19:20
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    You may want to read this [tutorial](http://docs.oracle.com/javase/tutorial/java/IandI/abstract.html). It's about abstract classes, but a lot of it applies to interfaces also. – ajb Jul 21 '14 at 19:39

1 Answers1

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List is an interface, and so it has no method implementations and cannot be instantiated. Your first two examples instantiate an ArrayList, which is a non-abstract class which implements the List interface.

sumitsu
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