About Question enthuware.ocpjp.v7.2.1368 :

[ewebxml]

Because the question states,
"Multiple threads need to access this information but none of them changes it."
This statement indicates that a Hashtable is not required.

Hashtable is synchronized, whereas HashMap is not.

In the scenario stated, synchronization is not required.

Please confirm.

[admin]

That is correct. That is why the correct answer is option 2, HashMap.
HTH,
Paul.

[romsky]

When the loading and the accessing the data happens in same time, then the answer is Hashtable.

[bioshark.dev]

The question also states:
"Which class would be the most appropriate to store such data if the values need not be kept in a sorted fashion?"

Based on this "wrong" clue I have chosen my answer TreeMap, otherwise HashMap was the clear choice. You even mention this in the explanation:

"TreeMap is used to keep the keys sorted which makes it a little bit slower than HashMap. "

So the question and the explanation is a bit ambiguous and contradictory!

[admin]

The statement says, "...need NOT be sorted...".

[bioshark.dev]

Must have been really tired to have missed that

P.S. I've taken and passed the exam yesterday. Big thanks to the entire team at EnthuWare.