java进阶 - Lambda表达式 - lambda和匿名类的区别35

package com.cyjt97.interior;

public class day04 {
    public static void main(String[] args) {
        use(new cs() {
            @Override
            public void show() {
                System.out.println("匿名类写法");
            }
        });
//        Lambda表达式,只允许操作函数式编程接口:有,且仅有一个抽象方法的接口
        use(()->{
            System.out.println("Lambda写法");
        });
    }

    public static void use(cs i){
        i.show();
    }
}
@FunctionalInterface
interface cs{
    void show();
}

　　

 

package com.cyjt97.interior;

import java.util.Random;

public class day04 {
    public static void main(String[] args) {
        use(new cs() {
            @Override
            public void show(String msg) {
                System.out.println("匿名类写法" + msg);
            }
        });
//        Lambda表达式,只允许操作函数式编程接口:有,且仅有一个抽象方法的接口
        use((String msg) -> {
            System.out.println("Lambda写法" + msg);
        });
//        如果 Lambda表达式的方法体代码只有一行代码可以省略大括号不写,同时要省略分号
        use(msg -> System.out.println("Lambda省略写法写法" + msg));
//        如果这行代码是 return语句,必须省略 return不写,同时也必须省略";"不写
        useRoomH(new RoomH() {
            @Override
            public int getRes() {
                Random r = new Random();
                int num = r.nextInt(100) + 1;
                return num;
            }
        });
        System.out.println("-----------------------------");
        useRoomH(new RoomH() {
            @Override
            public int getRes() {
                return new Random().nextInt(100)+1;
            }
        });
        System.out.println("-----------------------------");
        useRoomH(()->{return new Random().nextInt(100)+1;});
        System.out.println("-----------------------------");
        //相加数
        useCale(new cale(){
            @Override
            public int calc(int a, int b) {
                return a+b;
            }
        });
        System.out.println("-----------------------------");
        useCale(( a,  b)->{ a-b});
    }

    public static void use(cs i) {
        i.show("SB老板，不发工资");
    }

    private static void useRoomH(RoomH roomH) {
        int res = roomH.getRes();
        System.out.println(res);
    }
    private static void useCale(cale cale) {
        int cal = cale.calc(10,20);
        System.out.println(cal);
    }
}
//String
@FunctionalInterface
interface cs {
    void show(String msg);
}
//随机数
interface RoomH {
    int getRes();
}
//相加数
interface cale{
    int calc(int a,int b);
}