java中Lamda表达式讲解

a -> System.out.println("i like lamda-->"+a)

public interface Runnable{
	public abstract void run();
}

package com.haiyang.lamda;

public class TestLamda01 {

    //3、静态内部类，同样实现ILike接口
    static class Like2 implements ILike{
        @Override
        public void lamda() {
            System.out.println("i like lamda2");
        }
    }

    public static void main(String[] args) {
        ILike like = new Like();
        like.lamda();
        like = new Like2();
        like.lamda();

        //4、局部内部类
        class Like3 implements ILike{
            @Override
            public void lamda() {
                System.out.println("i like lamda3");
            }
        }
        like = new Like3();
        like.lamda();

        //5、匿名内部类，没有类的名称。必须借助接口或者父类
        like = new ILike() {
            @Override
            public void lamda() {
                System.out.println("i like lamda4");
            }
        };
        like.lamda();

        //6、lamda表达式
        like = ()->{
            System.out.println("i like lamda5");
        };
        like.lamda();
    }
}


//1、定义一个只有一个抽象方法的接口
interface ILike{
    abstract void lamda();
}

//2、实现类
class Like implements ILike{

    @Override
    public void lamda() {
        System.out.println("i like lamda1");
    }
}

package com.haiyang.lamda;

public class TestLamda02 {

    public static void main(String[] args) {
        ILive live = null;

        //Lamda简化
        live = (int a)->{
            System.out.println("I live you"+a);
        };
        live.live(1);

        //Lamda简化参数类型
        live = (a)->{
            System.out.println("I live you"+a);
        };
        live.live(2);

        //Lamda简化括号
        live = a->{
            System.out.println("I live you"+a);
        };
        live.live(3);

        //Lamda简化花括号（只有一条语句时）
        live = a->System.out.println("I live you"+a);
        live.live(4);
    }

}

interface ILive{
    abstract void live(int a);
}

package com.haiyang.lamda;

public class TestLamda02 {

    public static void main(String[] args) {
        ILive live = null;

        //Lamda简化
        live = (int a,int b)->{
            System.out.println("I live you"+a+b);
        };
        live.live(1,1);

        //Lamda简化参数类型（要去掉就要都去掉）
        live = (a,b)->{
            System.out.println("I live you"+a+b);
        };
        live.live(2,2);


        //Lamda简化花括号（只有一个语句时）
        live = (a,b)->System.out.println("I live you"+a+b);
        live.live(3,3);
    }

}

interface ILive{
    abstract void live(int a,int b);
}