← Exit to Module 12: Generics and Type Safety lessons
Module progress · 0%Lesson · 18 min
Module 12: Generics and Type Safety
Lesson focusBounded Type Parameters
Use upper and lower bounds to restrict acceptable types.
01 · 12 minWhy Generics?Locked02 · 16 minGeneric Classes & InterfacesLocked03 · 15 minGeneric MethodsLocked04 · 18 minBounded Type ParametersLocked05 · 16 minWildcards & VarianceLocked06 · 14 minType Erasure & LimitationsLocked07 · 30 minMini-Project: Generic Data StructureLocked
Upper bounds (<T extends Number>) limit types to Number or subclasses—enables numeric operations.
Lower bounds (? super T) support contravariance for consumers (e.g., Comparator<? super T>).
Remember PECS: Producer extends, Consumer super.