Java 讀取Properties檔案

標籤：

一、目標：讀取properties檔案，獲得類名來產生對象

二、類

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:"="兩邊不能有空格

vechileType=com.tong.spring.factory.Car

　　

4.Test.java

public class Test {@org.junit.Testpublic void test() {//讀取properties檔案，獲得類名來產生對象Properties pros = new Properties();try {//1.讀取要執行個體化的類名pros.load(Test.class.getClassLoader().getResourceAsStream("com/tong/spring/factory/spring.properties"));String vechileType = pros.getProperty("vechileType");//2.利用反射裝載類及用newInstance()執行個體化類Object o = Class.forName(vechileType).newInstance();Movable m = (Movable)o;m.run();} catch (Exception e) {e.printStackTrace();}}}

　　

5.運行結果：

 

 

6.若改成spring讀取xml檔案，則spring配置好後，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改為如下

public class Test {@org.junit.Testpublic void test() {BeanFactory factory = new ClassPathXmlApplicationContext("applicationContext.xml");Object o = factory.getBean("vehicle");Movable m = (Movable)o;m.run();}}

　　

 

Java 讀取Properties檔案