Provides implementation information to the caller?

Question

In JLS Capture Conversion , it discusses two ways to record a method signature reverse:

• public static void reverse(List<?> list);

• public static <T> void reverse(List<T> list);

  My question is why does the second provide implementation information to the caller? In particular, this example says that the second is undesirable because it provides implementation information to the caller.

Answer 1

List <? > will return elements of type Object when iterates through a sheet. (ex: lyst.get (..))

The <T> list will return elements of type T.

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