java8(2)函数式接口

函数式接口

就是只定义一个抽象方法(用来表示行为)的接口,用做Lambda表达式的类型。

public interface Comparator<T> {
    int compare(T o1, T o2);
}

public interface Runnable{
    void run();
}

java.util.function中给到的部分函数式接口

函数式接口	函数描述符	方法	default方法
Predicate<T>	T->boolean	test(T t)	and,negate,or,isEqual
Consumer<T>	T->void	accept(T t)	andThen
Function<T,R>	T->R	apply(T t)	compose,andThen,identity
Supplier<T>	()->T	get()	无
BiPredicate<L,R>	(L,R)->boolean	test(L l, R r)	and,negate,or
BiConsumer<T,U>	(T,U)->void	accept(T t, U u)	andThen
BiFunction<T,U,R>	(T,U)->R	apply(T t, U u)	andThen
UnaryOperator<T>	T->T
BinaryOperator<T>	(T,T)->T

---

原始类型特化
Predicate
IntPredicate
LongPredicate
DoublePredicate
Consumer
IntConsumer
LongConsumer
DoubleConsumer
Function<T,R>
IntFunction<R>,
IntToDoubleFunction,
IntToLongFunction,
LongFunction<R>,
LongToDoubleFunction,
LongToIntFunction,
DoubleFunction<R>,
ToIntFunction<T>,
ToDoubleFunction<T>,
ToLongFunction<T>
Supplier<T>
BooleanSupplier
IntSupplier
LongSupplier
DoubleSupplier
UnaryOperator<T>
IntUnaryOperator
LongUnaryOperator
DoubleUnaryOperator
BinaryOperator<T>
IntBinaryOperator
LongBinaryOperator
DoubleBinaryOperator
BiConsumer<T,U>
ObjIntConsumer<T>
ObjLongConsumer<T>
ObjDoubleConsumer<T>
BiFunction<T,U,R>
ToIntBiFunction<T,U>
ToLongBiFunction<T,U>
ToDoubleBiFunction<T,U>