It woiuld be nice if uou could use that syntax in Java, but you can't. It's not part of thelanguage. -13683360 <= rgb evaluates to a boolean (true/false)
and then (true/false) <= -13683381 is a bad operand because you cant't use <= with a boolean.
You need to break it into two comparisons the AND the reulsts together (-13683360 <= rgb) && (rgb <= -13683381)