Thread: Why is answer A correct and not answer B?? I always thought a class has to implement an interface!! Is it different with generics?

QUESTION: 163
A programmer must create a generic class MinMax and the type parameter of MinMax
must implement Comparable. Which implementation of MinMax will compile?
A. class MinMax<E extends Comparable<E>> {
E min = null;
E max = null;
public MinMax() {}
public void put(E value) { /* store min or max */ }
B. class MinMax<E implements Comparable<E>> {
E min = null;
E max = null;
public MinMax() {}
public void put(E value) { /* store min or max */ }
C. class MinMax<E extends Comparable<E>> {
<E> E min = null;
<E> E max = null;
public MinMax() {}
public <E> void put(E value) { /* store min or max */ }
D. class MinMax<E implements Comparable<E>> {
<E> E min = null;
<E> E max = null;
public MinMax() {}
public <E> void put(E value) { /* store min or max */ }

Correct Answer: A

Please check out the Generics tutorials for info on this: Bounded Type Parameters (The Java™ Tutorials > Learning the Java Language > Generics (Updated))

The link was fantastic advice. I found my answer. Many thanks

You're welcome.