maven 项目 查询部分关心的字段


<?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>
    <!--节点是有顺序的-->
    <!--先是jdbc,log4j-->
    <properties resource="jdbc.properties"></properties>
<!--
    <settings>
        <setting name="logImpl" value="LOG4J"/>
    </settings>-->
   <settings>
        <setting name="autoMappingBehavior" value="NONE"/>
    </settings>
 
    <typeAliases>
//别名 使用别名后 pageage name="cn.kitty.bean "后可自动生成与bean 同名类的别名 <package name="cn.kitty.bean"/> </typeAliases> <environments default="development"> <environment id="development"> <transactionManager type="JDBC"/> <dataSource type="POOLED"> <property name="driver" value="${jdbc.driver}"/> <property name="url" value="${jdbc.url}"/> <property name="username" value="${jdbc.username}"/> <property name="password" value="${jdbc.password}"/> </dataSource> </environment> </environments> <mappers> <!-- <mapper resource="mapper/IUserDao.xml"/>-->
//别名 <package name="cn.kitty.dao"></package> </mappers> </configuration>

settings 发现autoMappingBehavior的value的值有NONE,PARTIAL,FULL

NONE : 禁止自动配置

PARTIAL:(默认):自动配置所有的,有内部嵌套(association,collection)的除外。

FULL: 自动配置所有

 在小配置-------IUserDao.xml中添加  resultMap 节点

  在 select  节点 中 唯一添加标识符   resultMap="定义一个喜欢的名字"   此处与<resultMap  id="XXXX "/>相同

工具类 MybatisUtil

public class MybatisUtil {

    private  static InputStream is;
    public static SqlSessionFactory sqlSessionFactory;
 static {
     try {
         is=Resources.getResourceAsStream("mybaits1-config.xml");
     } catch (IOException e) {
         e.printStackTrace();
     }
     sqlSessionFactory =new SqlSessionFactoryBuilder().build(is) ;
 }
private MybatisUtil(){}
    public static SqlSession getSession(){
        return sqlSessionFactory.openSession();
    }

}

测试类 UserTest

 public class UserTest {
@Test
public void findAll() throws IOException {//查询
SqlSession session = MybatisUtil.getSession();
List<User> list = session.getMapper(IUserDao.class).findAll();
for (User user : list) {
System.out.println(user);
}
}

 

 

原文地址:https://www.cnblogs.com/cuixiaomeng/p/7531690.html