java常用函数接口

package com.bilibili;

import java.util.function.Consumer;
import java.util.function.Predicate;
import java.util.function.Supplier;

/**
 * @author WangYH
 * @version 2021.1.3
 * @date 2023/4/7 15:19
 */
public class Main {
   
    public static void main(String[] args) {
   

         //规定一些框架

        //供给型函数接口，提供对象
        Supplier<Student> studentSupplier = Student::new;
        //特别简洁,lambda表达式可以替换成方法引用
        studentSupplier.get().show();

        //消费型函数接口，使用对象
        Student student = new Student();
        STUDENT_CONSUMER.andThen(st -> System.out.println("后续操作")).accept(student);

        //Function,消费一个对象，对外供给一个对象
        //compose前置操作，andThen后置操作

        student.score = 70;
        boolean b = STUDENT_PREDICATE.and(stu -> stu.score > 90).test(student);
        //需要同时满足and条件才会返回 true

        //and or not操作

        if (!b) {
   
            System.out.println("Java还得多学");
        }

        //使用这些函数接口，可以使得代码更加简洁易读
    }

    public static class Student{
   
        int score;
        public void show() {
   
            System.out.println("我是学生!!");
        }
    }

    private static final Consumer<Student> STUDENT_CONSUMER = student -> System.out.println(student.toString() + " 好好吃饭!");
    private static final Predicate<Student> STUDENT_PREDICATE = student -> student.score >= 60;
}

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