Sybex flashcards (Boyarsky's and Selikoff's manual OCAJ 8)

[Miguel Callejón]

Deck #1, card #22 asks:

Which are final: String, StringBuilder, StringBuffer, arrays or ArrayList?

and the answer:

String is the only class in that list that is final

However StringBuilder and StringBuffer are final, too:
StringBuffer (Java 8)

public final class StringBuffer
extends Object
implements Serializable, CharSequence

StringBuilder (Java 8)

public final class StringBuilder
extends Object
implements Serializable, CharSequence

Or there is something I didn't understand?

[Jeanne Boyarsky]

No. That's wrong. I think we had immutable in mind. Added to the errata list.

In any case, you only have to know that String is final for the exam.