List or Array or Many makes more sense than "Plural" which is really
defined to mean "more than one" but I think in some cases you might
just have a single element or none at all. For example, this would be
valid I think:
@Max.Array( {
@Max(30, groups=JoeSixPack.class),
} )
although I don't know why you'd use an Array if you had a single
element but when you're coding things end up defined like this
sometimes.