Here is a complete list of all the functional interfaces available in the standard Java API.
| Interface |
Type |
| Runnable |
→ |
| BiConsumer(T, U) |
T, U → |
| BiFunction(T, U, R) |
T, U → R |
| BinaryOperator |
T, T → R |
| BiPredicate<T, U> |
T, U → boolean |
| BooleanSupplier |
→ boolean |
| Consumer |
T → |
| DoubleBinaryOperator |
double, double → double |
| DoubleConsumer |
double → |
| DoubleFunction |
double → R |
| DoublePredicate |
double → boolean |
| DoubleSupplier |
boolean → |
| DoubleToIntFunction |
double → int |
| DoubleToLongFunction |
double → long |
| DoubleUnaryOperator |
double → double |
| Function<T, R> |
T → R |
| IntBinaryOperator |
int → int |
| IntConsumer |
int → |
| IntFunction |
int → R |
| IntPredicate |
int → boolean |
| IntSupplier |
→ int |
| IntToDoubleFunction |
int → double |
| IntToLongFunction |
int → long |
| IntUnaryOperator |
int → int |
| LongBinaryOperator |
long, long → long |
| LongConsumer |
long → |
| LongFunction |
long → R |
| LongPredicate |
long → boolean |
| LongSupplier |
→ long |
| LongToDoubleFunction |
long → double |
| LongToIntFunction |
long → int |
| LongUnaryOperator |
long → long |
| ObjDoubleConsumer |
T, double → |
| ObjIntConsumer |
T, int → |
| ObjLongConsumer |
T, long → |
| Predicate |
T → boolean |
| Supplier |
→ T |
| ToDoubleBiFunction<T, U> |
T, U → double |
| ToDoubleFunction |
T → double |
| ToIntBiFunction<T, U> |
T, U → int |
| ToIntFunction |
T → int |
| ToLongBiFunction<T, U> |
T, U → long |
| ToLongFunction |
T → long |
| UnaryOperator |
T → T |