新手详细讲解：spring加载配置文件中的数据

新手详细讲解：spring加载配置文件中的数据

1.首先我们看一下目录结构和要用到的文件
这里我创建了SomeValue2.java,TestCase2.java,BasicValue.xml,db.properties

2.db.properties

3.SomeValue2.java

package Value;

public class SomeValue2 {
	private String userName;
	public void setUserName(String userName) {
		this.userName=userName;
		
	}
	@Override
	public String toString() {
		return "SomeValue2 [userName=" + userName + "]";
	}
	

}

4.BasicValue.xml
配置文件中定义了SomeValue2的bean通过子元素property中userName的set方法赋值，通过db绑定上方读取文件的信息。

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:aop="http://www.springframework.org/schema/aop" 
	xmlns:tx="http://www.springframework.org/schema/tx" 
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:mvc="http://www.springframework.org/schema/mvc"
	xmlns:util="http://www.springframework.org/schema/util"
	xsi:schemaLocation="http://www.springframework.org/schema/beans   
    		http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
    		http://www.springframework.org/schema/context 
    		http://www.springframework.org/schema/context/spring-context-2.5.xsd    
			http://www.springframework.org/schema/aop    
    		http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
    		http://www.springframework.org/schema/tx  
    		http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
    		http://www.springframework.org/schema/mvc
       		http://www.springframework.org/schema/mvc/spring-mvc.xsd
       		http://www.springframework.org/schema/util
    		http://www.springframework.org/schema/util/spring-util-3.0.xsd">
    		<!-- 
    		加载配置文件
    		将其中的数据封装到properties中
    		spring容器会在类路径下搜索改配置文件
    		 -->
    		 <util:properties id="db" location="classpath:db.properties">
    		 	
    		 </util:properties>
    		 <bean id="some2" class="Value.SomeValue2">
    		 <!-- 使用spring表达式访问bean属性 -->
    		 	<property name="userName" value="#{db.username}"></property>
    		 </bean>
</beans>

4.TestCase2.java
这里的测试类大家就看test6（）就行，其他的是之前的测试，谷咕咕懒得删了。

package test;

import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import IOC2.A;
import IOC2.Rest;
import SpringScope.HelloBean;
import SpringScope.PsersonBean;
import Value.BasicValue;
import Value.Page;
import Value.SomeValue;
import Value.SomeValue2;
import Web.UserServlet;

public class TestCase2 {
	private ApplicationContext ac;
	private final static String XML="BasicValue.xml";
	@Before
	public void init() {
//		ApplicationContext 
		ac=new ClassPathXmlApplicationContext(XML);
	}
	@Test
	public void test6() {
		SomeValue2 some2=ac.getBean("some2",SomeValue2.class);
		System.out.println(some2);
		
	}
}

最后我们看下结果，成功将张三这个数据读取了出来