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"));