Wildcards

6

Which of the following is incorrect statement regarding the use of generics and 

parameterized types in Java?

A. Generics provide type safety by shifting more type checking responsibilities to the compiler.
B. Generics and parameterized types eliminate the need for down casts when using Java Collections.
C. When designing your own collections class (say, a linked list), generics and parameterized types allow you to achieve type safety with just a single class definition as opposed to defining multiple classes.
D. All of the mentioned

7

Which of these is an correct way making a list that is upper bounded by class 

Number?

A. List
B. List
C. List(? extends Number)
D. List(? UpperBounds Number)

8

Which of these keywords is used to upper bound a wildcard?

A. stop
B. bound
C. extends
D. implements

9

What is use of wildcards?

A. It is used in cases when type being operated upon is not known.
B. It is used to make code more readable.
C. It is used to access members of super class.
D. It is used for type argument of generic method

10

Which of these is wildcard symbol?

A. ?
B. !
C. %
D. &