What's the difference between unbounded wildcard type List<?> and raw type List?

Question

Could you help me understand the difference between unbounded wildcard type List and raw type List?

List b;    // unbounded wildca         


        

Answer 1

Here's a summary of the three:

• List: A list with no type parameter. It is a list whose elements are of any type -- the elements may be of different types.

• List: A list with an unbounded type parameter. Its elements are of a specific, but unknown, type; the elements must all be the same type.

• List: A list with a type parameter called T. The supplied type for T must be of a type that extends E, or it is not a valid type for the parameter.