第一和mabatis项目记录

一、添加maven依赖

去 maven仓库中找自己需要的版本

二、构建sqlSessionFactory

String resource = "org/mybatis/example/mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);

三、编写配置文件(环境+mapper)

<?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="${driver}"/>
        <property name="url" value="${url}"/>
        <property name="username" value="${username}"/>
        <property name="password" value="${password}"/>
      </dataSource>
    </environment>
  </environments>
  <mappers>
    <mapper resource="org/mybatis/example/BlogMapper.xml"/>
  </mappers>
</configuration>

四、写DAO+MAPPER.XML

package com.yzm.dao;
import com.yzm.pojo.User;
import java.util.List;
public interface UserDao {
    List<User> getUserList();
}

<?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="com.yzm.dao.UserDao">
    <select id="getUserList" resultType="com.yzm.pojo.User">
        select * from mybatis.user;
    </select>
</mapper>

五、获取session然后执行

    @Test
    public  void test(){
    	   try (SqlSession sqlSession = MybatisUtils.getSqlSession()){
            UserDao mapper = sqlSession.getMapper(UserDao.class);
            List<User> userList = (List<User>) mapper.getUserList();
            for (User user : userList) {
                System.out.println(user.getName()+user.getPassword());
            }
        }
    }

六、出现的问题

maven项目中如果xml文件没在resource文件夹下是不会出现再目标编码里面的。

    <build>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>true</filtering>
            </resource>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>true</filtering>
            </resource>
        </resources>
    </build>