今天配置Spring，遇到一个很奇葩的问题：
Spring.xml的配置文件内容：
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:tx="http://www.springframework.org/schema/tx"
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/tx
http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
http://www.springframework.org/schema/context/spring-context.xsd
">
测试出错：
Tests in error:
instanceSpring(com.qunar.studyspring.SpringTest): Line 1 in XML document from class path resource [spring.xml] is invalid; nested exception is org.xml.sax.SAXParseException; systemId: http://www.springframework.org/schema/tx/; lineNumber: 1; columnNumber: 55; 在 publicId 和 systemId 之间需要有空格。
百思不得其解，后来在网络上搜索了半天，结论就是：前一个是publicID，后一个是SystemId，是一一对应的，位置不能颠倒
http://www.springframework.org/schema/beans publicID
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd SystemId
修改之后：
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:tx="http://www.springframework.org/schema/tx"
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.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
">
黑色部分就是给我留下深刻记忆的部分，次序颠倒了