目录

 

 

1、创建数据库

2、创建entity

3、TypeHandler

4、mapper.xml

5、mapper

6、controller

---

 

1、创建数据库

CREATE TABLE `user` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '主键,其它表中的使用user_id',
  `name` varchar(100) NOT NULL DEFAULT '',
  `address` varchar(100) NOT NULL DEFAULT '',
  `favorites` varchar(200) NOT NULL DEFAULT '',
  `create_user_id` bigint(20) DEFAULT NULL COMMENT '创建人userId',
  `modified_user_id` bigint(20) DEFAULT NULL COMMENT '修改人userId',
  `gmt_create` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
  `gmt_modified` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '修改时间',
  `is_deleted` int(11) NOT NULL DEFAULT '0' COMMENT '1表示删除,0表示未删除',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=9 DEFAULT CHARSET=utf8mb4 COMMENT='用户表';


INSERT INTO  `user` (`id`, `name`, `address`, `favorites`, `create_user_id`, `modified_user_id`, `gmt_create`, `gmt_modified`, `is_deleted`) VALUES ('4', 'test', '地址', '喜欢1,喜欢2，喜欢3', NULL, NULL, '2020-11-03 12:40:26', '2021-03-22 15:43:22', '0');

2、创建entity

@Data
public class User implements Serializable {
    private static final long serialVersionUID = 1L;
    private Long id;
    private String name;
    private String address;
    private List<String> favorites;
}

3、TypeHandler

@MappedJdbcTypes(JdbcType.VARCHAR)  //数据库类型
@MappedTypes(List.class) //java中类型
public class List2VarcharHandler implements TypeHandler<List<String>> {

    /**
     * @param ps
     * @param i
     * @param strings
     * @param jdbcType
     * @throws SQLException
     */
    @Override
    public void setParameter(PreparedStatement ps, int i, List<String> strings, JdbcType jdbcType) throws SQLException {
        StringBuffer sb = new StringBuffer();
        for (String temp : strings) {
            sb.append(temp).append(",");
        }
        ps.setString(i, sb.toString());
    }

    @Override
    public List<String> getResult(ResultSet resultSet, String columnName) throws SQLException {
        String s = resultSet.getString(columnName);
        if (s != null) {
            return Arrays.asList(s.split(","));
        }
        return null;
    }

    @Override
    public List<String> getResult(ResultSet resultSet, int i) throws SQLException {
        String s = resultSet.getString(i);
        if (s != null) {
            return Arrays.asList(s.split(","));
        }
        return null;
    }

    @Override
    public List<String> getResult(CallableStatement callableStatement, int i) throws SQLException {
        String s = callableStatement.getString(i);
        if (s != null) {
            return Arrays.asList(s.split(","));
        }
        return null;
    }
}

4、mapper.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="com.yg.springboot.mapper.UserMapper">

   <resultMap id="BaseMap" type="com.yg.springboot.domain.User">
        <id property="id" column="id"/>
        <result property="name" column="name"/>
        <result property="address" column="address"/>
        <result property="favorites" column="favorites" typeHandler="com.yg.springboot.typehandler.List2VarcharHandler"/>
    </resultMap>


    <select id="getAll" resultMap="BaseMap">
        select
        id,
        name,
        address,
        favorites
        from user
    </select>

    <insert id="addUser" parameterType="com.yg.springboot.domain.User">
       insert into
       user(`name` ,address,favorites)
       values(
       #{name},
       #{address},
       #{favorites,typeHandler=com.yg.springboot.typehandler.List2VarcharHandler})
    </insert>


</mapper>

5、mapper

public interface UserMapper {

    List<User> getAll();

    Integer addUser(User user);

}

6、controller

 @RequestMapping(value = {"getUserAll"})
    public Object getUserAll(HttpServletRequest req, HttpServletResponse resp) {
        return userMapper.getAll();
    }
    
    @RequestMapping(value = {"addUser"})
    public Object addUser(User user) {

        List<String> list = new ArrayList<>();
        list.add("111");
        list.add("222");
        list.add("333");

        user.setAddress("地址");
        user.setName("姓名");
        user.setFavorites(list);
       return userMapper.addUser(user);

    }