Java继承和多态

class Father{public int s=20;public void prints(){System.out.println("Hello Father " + s);}}public class HelloWorld extends Father {int s=30, t=40;public void prints(){System.out.println("Hello World " + s);}public static void main(String[] args) {Father tmp = new HelloWorld();tmp.prints();System.out.println(tmp.s);/*Scanner reader = new Scanner(System.in);while(reader.hasNextInt()){int tmps = reader.nextInt();System.out.printf("%03d\n",tmps);}*/}}

输出：

Hello World 30
20

注意方法是覆盖，类的变量是隐藏，不能实现覆盖。而多态只对覆盖关系才能体现出来。