Java 多态

Feeder feeder=new Feeder();
Animal animal=new Dog();
Food food=new Bon();
feeder.feed(animal,food);//给狗喂肉狗骨头
anmal=new Cat();
foof=new Fish();
feeder.feed(animal,food);给猫喂鱼

class Base
{
String var="BaseVar";           //实例变量
static String staticvar="StaticBaseVar"  //静态变量


void metod()           //实例方法
system.out.Println("Base method");

}
static void staticMethod()  //静态方法
{
syso.out.printIn("Static Base method");
}
}
public class Sub extends Base
{
String var="Subvar";  
static String staticVar="staticSubvar";

void method()  //覆盖父类的method()方法
{
Sysotem.out.printIn("Static sub method");
}
static void staticMethod()  //隐藏父类的staticMethod()方法
{
system.out.printin("static sub method");
}
String subVar="Var only belonging to  sub";
void subMethod()
{
System.out.pritn("Method only belonging to sub");
}
public static void main(String args[])
{
Base who=new Sub();                  //who被声明为Base类型，引用Sub
System.out.printin("who.var"+who.var);  //打印Base类的var变量
System.out.printIn("who.staticVar"+wh.saticVar); //打印Base类staticVar变量
who.metod();             //打印Sub实例的method()方法
who.staticMethod();        //打印Base类的staticMethod();
}
}