package org.lxh.demo15.factorydemo01 ; interface Fruit{ public void eat() ; // 吃水果 } class Apple implements Fruit{ public void eat(){ // 覆写eat()方法 System.out.println("** 吃苹果"); } }; class Orange implements Fruit{ public void eat(){ System.out.println("** 吃橘子") ; } }; class Factory{ public static Fruit getInstance(String className){ Fruit fruit = null ; try{ fruit = (Fruit)Class.forName(className).newInstance() ; }catch(Exception e){ e.printStackTrace() ; } return fruit ; } }; public class FactoryDemo01{ public static void main(String args[]){ Fruit f = Factory.getInstance("org.lxh.demo15.factorydemo01.Apple") ; if(f!=null){ f.eat() ; } } };
package org.lxh.demo15.factorydemo02 ; import java.util.Properties ; import java.io.File ; import java.io.FileOutputStream ; import java.io.FileInputStream ; interface Fruit{ public void eat() ; // 吃水果 } class Apple implements Fruit{ public void eat(){ // 覆写eat()方法 System.out.println("** 吃苹果"); } }; class Orange implements Fruit{ public void eat(){ System.out.println("** 吃橘子") ; } }; class Init{ public static Properties getPro(){ Properties pro = new Properties() ; File f = new File("d:\\fruit.properties") ; // 找到属性文件 try{ if(f.exists()){ // 文件存在 pro.load(new FileInputStream(f)) ; // 读取属性 }else{ pro.setProperty("apple","org.lxh.demo15.factorydemo02.Apple") ; pro.setProperty("orange","org.lxh.demo15.factorydemo02.Orange") ; pro.store(new FileOutputStream(f),"FRUIT CLASS") ; } }catch(Exception e){} return pro ; } }; class Factory{ public static Fruit getInstance(String className){ Fruit fruit = null ; try{ fruit = (Fruit)Class.forName(className).newInstance() ; }catch(Exception e){ e.printStackTrace() ; } return fruit ; } }; public class FactoryDemo02{ public static void main(String args[]){ Properties pro = Init.getPro() ; Fruit f = Factory.getInstance(pro.getProperty("apple")) ; if(f!=null){ f.eat() ; } } };
来源:https://www.cnblogs.com/tszr/p/12416999.html