boolean (DfType type) { TypeConstraint constraint = TypeConstraint.fromDfType(type); return constraint.isExact(JAVA_UTIL_OPTIONAL) || constraint.isExact(OptionalUtil.OPTIONAL_DOUBLE) || constraint.isExact(OptionalUtil.OPTIONAL_INT) || constraint.isExact(OptionalUtil.OPTIONAL_LONG) || constraint.isSubtypeOf(OptionalUtil.GUAVA_OPTIONAL); }