Steve, this causes the exception in either version:

.when(cb.gt(cb.count(expense_), cb.literal(0L)), cb.literal(true))

This is a workaround for both versions (using a number as literal):

.when(cb.gt(cb.count(expense_), cb.literal(0L)), cb.literal(1L))

This is a workaround only for 5.0.2 (using a Java boolean literal directly instead of wrapped by cb.literal()):

.when(cb.gt(cb.count(expense_), 0L), true)