标签:style blog color java io ar div new
// Superclass (parent class) class Fruit{ public String flavor; } // Subclass (child class) class Apple extends Fruit { public String variety; } //downcasting Apple a = new Apple(); Fruit f = a; Apple c = (f instanceof Apple) ? (Apple)f : null;
class Rectangle{ public int w = 10, h = 10; public int getArea() { return w * h; } } class Triangle extends Rectangle{ //调用父构造函数 public Triangle() { super(); } @Override public int getArea() { return w * h / 2; } } Rectangle o = new Triangle(); o.getArea(); // (50) calls Triangle‘s version
如果用关键字 final, 比如: public final int getArea() { return w * h; } 这个方法不能被子类重写.
参考文献: Java Quick Syntax Reference by Mikael Olsson
Java 语法 索引 ----- 继承(Inheritance) 和重写(Overriding),布布扣,bubuko.com
Java 语法 索引 ----- 继承(Inheritance) 和重写(Overriding)
标签:style blog color java io ar div new
原文地址:http://www.cnblogs.com/timba/p/3900451.html