hi SP,
I think it is better to understand difference between the Keywords and Reserved word. The reserved words are set of words defined by the language and the user cannot use those words other then specified purpose.
The Keywords are the reserved words that are currently used by that language version, like Java 2.0 does not support the use of goto and const. But the persons who developed jave have defined these words meaning that it may be made possible to be used by some other versions.
Hope this will clear u'r doubt
So the case one is ruled out. coming to the case 2, the literals null, true and false are not considered as reserved words.