java8的接口默认方法实例

public class AppInterfaceDefaultMethod {

    public static interface DefaultMethodDemo {
        //定义默认方法， 默认方法前面加default关键字， 后面跟方法声明和方法体
        default void demo(String input) {
            System.out.println(input);
        }

        void doSomething();
    }

    public static class DemoClass implements DefaultMethodDemo {
        @Override
        public void doSomething() {
            System.out.println("do something");
        }
    }

    public static class DemoClassOverrideDemo implements DefaultMethodDemo {
        //重写了默认方法
        @Override
        public void demo(String input) {
            System.out.println("demo " + input + " by override method");
        }

        @Override
        public void doSomething() {

            System.out.println("do something");
        }
    }

    public static void main(String[] args) {
        DefaultMethodDemo demo = new DemoClass();
        demo.demo("abc");

        DefaultMethodDemo demoOverride = new DemoClassOverrideDemo();
        demoOverride.demo("abc");
    }
}