About Question enthuware.ocpjp.v7.2.1451 :

[alkour]

Hi,

What does means Option:

If passed a null, it should return false.

I assume it could be right answer, as

For any non-null reference value x, x.equals(null) should return false.

[admin]

Yes, it is the right option.

[timwaagh]

'For any non-null reference value x, x.equals(null) should return false.' is what the explanation says. The reason i chose 'none of the above' was because i was thinking on what if the object it is called upon is null as well. Now that i am thinking of it, if x==null, x.equals(null) would throw a NullPointerException? is that what happens? Would you care to expand the explanation a bit to cover this case?

[admin]

As the explanation says, x.equals(null) should return false.
It will not throw NPE because you are not invoking any method on null.

You may try it out as well.