lambda表达式的逐步推导以及应用

package lambda;

public class TestLambda {
    //2.静态内部类

    static class Like2 implements ILike{
        @Override
        public void lambda() {
            System.out.println("i like 2");
        }
    }


    public static void main(String[] args) {
        ILike like = new Like1();//接口是父类,父类引用指向子类对象
        like.lambda();

        like = new Like2();//like和上方的名字一样
        like.lambda();

        class Like3 implements ILike{//3.局部内部类
            @Override
            public void lambda() {
                System.out.println("i like 3");
            }
        }
        like = new Like3();
        like.lambda();

        //4.匿名内部类
        like = new ILike() {
            @Override
            public void lambda() {
                System.out.println("i like 4");
            }
        };
        like.lambda();

        //5.用lambda表达式去简化
        like = ()->{
            System.out.println("i like 5");
        };
        like.lambda();

    }
}


//定义一个函数式接口//一个接口里只有一个方法
interface ILike{
    void lambda();
}

//1.外部类
class Like1 implements ILike{
    @Override
    public void lambda() {
        System.out.println("i like 1");
    }
}

package lambda;

public class TestLambda2 {
    public static void main(String[] args) {
        ILove iLove = null;
        iLove= (int a) -> {//通过接口创建对象
            System.out.println("i   love\t"+a);
        };
        iLove.love(3);
    }
}

interface ILove{
    void love(int a);
}