Since Groovy 1.7.4 we can use simple type arrays in a conditional context. If the array is empty we get false, otherwise true is returned. Support for byte, short, int, long, float, double, char and boolean type arrays is added to Groovy. This functionality already worked for Object arrays, but now also for simple type arrays.
def bytes =  as byte def ints = [1,2,4] as int def floats =  as float def booleans = [true, false] as boolean assert !bytes assert ints assert !floats assert booleans