Interface WildcardType

All Superinterfaces:
AnnotationTarget, Type

public interface WildcardType extends Type
A wildcard type. May have 3 forms:
  • ? extends Number: has an upper bound
  • ? super Number: has a lower bound
  • ?: unbounded, has an implicit upper bound of java.lang.Object
Note that ? is equivalent to ? extends Object and is represented as such. Therefore, either upperBound() or lowerBound() always returns non-null.