【Java】Java工厂模式之简单工厂

package com.app;import java.util.Date;/* * 工厂模式：简单工厂、工厂方法、抽象工厂 *  * */public class  Test0718_Factory {public static void main(String[] args) {Fruit.FruitJudge(new Date());Fruit.FruitJudge(5);Fruit.FruitJudge(new Fruit());Fruit.FruitJudge(new Cherry());Fruit.FruitJudge(new Apple());System.out.println();Fruit fruit1 = Fruit.getFruit(1);Fruit fruit2 = Fruit.getFruit(2);fruit1.grow();fruit2.grow();((Apple)fruit2).m1();}}class Fruit {public void grow(){System.out.println("水果在生长");}public static void FruitJudge(Object obj){if(! (obj instanceof Fruit)){System.out.println("参数类型不兼容");}  else {if(obj instanceof Cherry){Cherry f = (Cherry)obj;//造型，高->低f.grow();} else if(obj instanceof Apple){Apple f = (Apple)obj;f.grow();f.m1();//强转后，可以明确调用子类新加的成员} else {Fruit f = (Fruit)obj;f.grow();}}}//简单工厂模式，根据值的不同返回不同的子类实例public static Fruit getFruit(int code){Fruit obj = null;if(code==1) {obj = new Cherry();} else if(code==2) {obj = new Apple();} else {obj = new Fruit();}return obj;}}class Cherry extends Fruit {public void grow(){System.out.println("樱桃在生长");}}class Apple extends Fruit {public void grow(){System.out.println("苹果在生长");}public void m1(){ System.out.println("苹果的m1"); }}

执行结果：

---------- 运行 ----------
参数类型不兼容
参数类型不兼容
水果在生长
樱桃在生长
苹果在生长
苹果的m1


樱桃在生长
苹果在生长
苹果的m1


输出完成 (耗时 0 秒) - 正常终止