摘要：
class Fu{ int num = 5; void method1() { System.out.println("fu method_1"); } void method2() { System.out.println("fu m... 阅读全文
摘要：
abstract class Animal{abstract void eat();}class Cat extends Animal{public void eat(){System.out.println("吃鱼");}public void catchMouse(){System.out.pr... 阅读全文