Tokens, Values, and Variables - The Java Programming Language - page 240

fused. For example, the Latin capital letter n "N" and the Greek capital
n """ look alike but are different characters ( \u004e and \u039d , respect-
ively). The only way to avoid confusion is to write each identifier in one
languageand thus in one known set of charactersso that programmers
trying to type the identifier will know whether you meant E or E . [5]

[5] One is a Cyrillic letter, the other is ASCII . Guess which is which and win a prize.

Identifiers can be as long as you like, but use some taste. Identifiers
that are too long are hard to use correctly and actually obscure your
code.

7.1.5. Keywords

Language keywords cannot be used as identifiers because they have
special meaning within the language. The following table lists the
keywords (keywords marked with a

are reserved but currently un-

used):

abstract continue for new switch

assert default package synchronized

goto

boolean do if private this

break double implements protected tHRow

byte else import public tHRows