List<? extends Base> list
List<Base> list
Is there any difference between the two declarations?
Thanks,
List<? extends Base> list List<Base> list Is there any difference between the two declarations?
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List<? extends Base> list
List<Base> list
Is there any difference between the two declarations?
Thanks,
Yes.
List<Base>can contain a mixture of different things that all derive fromBase.List<? extend Base>contains homogeneous items (in the sense that they must all derive from some specific, unknown type that in turn derives fromBase).Put another way,
List<? extends Base>is the base class forList<T extends Base>. So you can pass aList<T extends Base>to any method that takes aList<? extends Base>. The same is not true for methods that take aList<Base>.