BiConsumer函数式接口源码重点
1.BiConsume是一个函数式接口,里面只有一个需要实现的方法是 void accept(T t, U u),表示一个接受两个输入参数但不返回结果的操作,通常用于处理键值对,key是一个参数,值是一个参数,BiConsumer函数式接口与Consumer函数式接口的区别是Consumer的void accept(T t),表示一个接受单个输入参数但不返回结果的操作,Consumer源码可以看我这篇文章 Consumer
2.BiConsumer<T, U> andThen(BiConsumer<? super T, ? super U> after)用于拼接多个BiConsumer的accept(T t, U u)方法,按顺序执行操作,如果前面的操作抛出异常,则后面的操作不会执行
3.Consumer接口方法
方法名 | 作用 |
---|---|
void accept(T t, U u) | 表示一个接受两个输入参数但不返回结果的操作 |
default BiConsumer andThen(BiConsumer after) | 返回一个组合的新BiConsumer,在新的BiConsumer会先对两个参数此BiConsumer的accept操作再执行after中的accept操作 |
BiConsumer函数式接口源码
package java.util.function;
import java.util.Objects;
/**
* Represents an operation that accepts two input arguments and returns no
* result. This is the two-arity specialization of {@link Consumer}.
* Unlike most other functional interfaces, {@code BiConsumer} is expected
* to operate via side-effects.
* 表示接受两个输入参数但不返回结果的操作。这是Consumer的两个算术特化。
* 与大多数其他功能接口不同,BiConsumer预期通过副作用运行。
*
* <p>This is a <a href="package-summary.html">functional interface</a>
* whose functional method is {@link #accept(Object, Object)}.
* 这是一个函数接口,其函数方法是accept(Object, Object)
*
* @param <T> the type of the first argument to the operation
* @param <U> the type of the second argument to the operation
*
* @see Consumer
* @since 1.8
*/
@FunctionalInterface
public interface BiConsumer<T, U> {
/**
* Performs this operation on the given arguments.
* 对给定参数执行此操作。
*
* @param t the first input argument
* @param u the second input argument
*/
void accept(T t, U u);
/**
* Returns a composed {@code BiConsumer} that performs, in sequence, this
* operation followed by the {@code after} operation. If performing either
* operation throws an exception, it is relayed to the caller of the
* composed operation. If performing this operation throws an exception,
* the {@code after} operation will not be performed.
* 返回一个组合的BiConsumer,它依次执行此操作和after操作。
* 如果执行任何一个操作都会引发异常,则会将异常转发给组合操作的调用方。
* 如果执行此操作引发异常,则不会执行after操作。
*
* @param after the operation to perform after this operation
* @return a composed {@code BiConsumer} that performs in sequence this
* operation followed by the {@code after} operation
* @throws NullPointerException if {@code after} is null
*/
default BiConsumer<T, U> andThen(BiConsumer<? super T, ? super U> after) {
Objects.requireNonNull(after);
return (l, r) -> {
accept(l, r);
after.accept(l, r);
};
}
}