Java-马士兵设计模式学习笔记-工厂模式-模拟Spring读取Properties文件

一、目标：读取properties文件，获得类名来生成对象

二、类

1.Movable.java

public interface Movable {

	void run();

}

　　

2.Car.java

public class Car implements Movable {



	public void run() {

		System.out.println("Car running...............");

	}

	

}

　　

3.spring.properties

PS:"="两边不能有空格

vechileType=com.tong.spring.factory.Car

　　

4.Test.java

public class Test {

	

	@org.junit.Test

	public void test() {

		

		//读取properties文件，获得类名来生成对象

		Properties pros = new Properties();

		

		try {

			//1.读取要实例化的类名

			pros.load(Test.class.getClassLoader().getResourceAsStream("com/tong/spring/factory/spring.properties"));

			String vechileType = pros.getProperty("vechileType");

			

			//2.利用反射装载类及用newInstance()实例化类

			Object o = Class.forName(vechileType).newInstance();

			Movable m = (Movable)o;

			m.run();

		} catch (Exception e) {

			e.printStackTrace();

		}

	}

}

　　

5.运行结果：

 

 

6.若改成spring读取xml文件，则spring配置好后，增加applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"

       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

       xsi:schemaLocation="http://www.springframework.org/schema/beans

           http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">



  <bean id="vehicle" class="com.tong.spring.factory.Car">

  </bean>



  <!-- more bean definitions go here -->



</beans>

　　

7.Test.java改为如下

public class Test {

	

	@org.junit.Test

	public void test() {

		

		BeanFactory factory = new ClassPathXmlApplicationContext("applicationContext.xml");

		Object o = factory.getBean("vehicle");

		Movable m = (Movable)o;

		m.run();

	}

}