如何在Java的lambda表达式中使用Consumer和BiConsumer接口？
Consumer接口是一个预定义的函数接口，可以在创建lambda 表达式或方法引用时使用。此接口表示接受单个输入参数且不返回任何内容的操作。它只包含一个名为accept()的方法。BiConsumer 接口类似于Consumer接口，接受两个输入参数，不返回任何内容。
语法
@FunctionalInterface public interface Consumer<T>@FunctionalInterface public interface BiConsumer<T, U>
示例
import java.util.*;
import java.util.function.*;
public class ConsumerBiConsumerTest {
public static void main(String[] args) {
Consumer<String> c = (x) -> System.out.println(x.toLowerCase()); // lambda 表达式
c.accept("Raja");
Consumer<Integer> con = (x) -> { // lambda 表达式
System.out.println(x + 10);
System.out.println(x - 10);
};
con.accept(10);
BiConsumer<Strng, String> bc = (x, y) -> { System.out.println(x + y);};
bc.accept("1", "2");
List<Person> plist = Arrays.asList(new Person("RAJA"), new Person("ADITHYA"));
acceptAllEmployee(plist, p -> System.out.println(p.name));
acceptAllEmployee(plist, p -> {p.name = "unknown";});
acceptAllEmployee(plist, p -> System.out.println(p.name));
}
public static void acceptAllEmployee(List<Person> plist, Consumer<P> con) {
for(Person p : plist) {
con.accept(p);
}
}
}// Person class
class Person {
public String name;
public Person(String name) {
this.name = name;
}
}输出结果
raja 20 0 12 RAJA ADITHYA unknown unknown