mybatis 中configuration.xml报错

Question

configuration.xml代码:<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE configuration  PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"><configuration>      <environments default="development" >        <environment id="development" >            <transactionManager type="JDBC" />            <dataSource type="POOLED">                <property name="driver" value="com.mysql.jdbc.Driver" />                <property name="url" value="jdbc:mysql://localhost:3306/test" />                <property name="username" value="root" />                <property name="password" value="123" />            </dataSource>        </environment>    </environments>    <mappers>        <mapper resource="mybatistest/Trainee.xml"/>    </mappers></configuration>映射文件Trainee.xml：<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE mapper  PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"  "http://mybatis.org/dtd/mybatis-3-mapper.dtd">   <mapper namespace="mybatistest">         <select id="selectUserById" parameterType="int" resultType="mybatistest.Trainee">          select * from person where id=#{id}         </select>   </mapper>测试类Test.java代码：package mybatistest;import java.io.IOException;import org.apache.ibatis.io.Resources;import org.apache.ibatis.session.SqlSession;import org.apache.ibatis.session.SqlSessionFactory;import org.apache.ibatis.session.SqlSessionFactoryBuilder;import mybatistest.Trainee;public class Test { public static void main(String[] args){  SqlSessionFactory factory=null;  try{   factory=new SqlSessionFactoryBuilder().build(Resources.getResourceAsStream("mybatistest/Configuration.xml"));  }catch(IOException e){   e.printStackTrace();  }  SqlSession sqlSession=factory.openSession();  Trainee t=(Trainee)sqlSession.selectOne("mybatis.selectUserById", 5);  System.out.println(t.getName()); }}目录结构：不做任何修改，关掉重新打开eclipse，在eclipse中会报出两种错误：一种是在声明<!DOCTYE...>行报“content is not allowed in prolog.”另一种是在代码<environments default="development" > 行报：Element type "environments" must be followed by either attribute specifications, ">" or "/>".运行结果：第一种：找不到configuration.xml第二种：Caused by: org.xml.sax.SAXParseException; lineNumber: 6; columnNumber: 18; 元素类型 "environments" 必须后跟属性规范 ">" 或 "/>"。求解答，谢谢！

Answer 1

Class.getResourceAsStream(String path) ： path 不以’/'开头时默认是从此类所在的包下取资源，以’/'开头则是从ClassPath根下获取。其只是通过path构造一个绝对路径，最终还是由ClassLoader获取资源。 

所以你应该改为factory=new SqlSessionFactoryBuilder().build(Resources.getResourceAsStream("Configuration.xml"));