爱上一个人,心会一直低,低到泥土里,在土里开出花来,如此卑微却又如此欣喜。
pom 增加 jar 包
<!-- 版本要用 4.1.5 的，不然会有其他问题-->
<mapper.version>4.1.5</mapper.version>
<dependency>
<groupId>tk.mybatis</groupId>
<artifactId>mapper</artifactId>
<version>${mapper.version}</version>
</dependency>
Spring - mybatis 的配置文件
<!--在Spring中配置Mapper接口 -->
<bean class="tk.mybatis.spring.mapper.MapperScannerConfigurer">
<!-- 为映射器接口文件设置基本的包路径 -->
<property name="basePackage" value="com.platform.dao" />
</bean>
通用 MyMapper
import tk.mybatis.mapper.common.Mapper;
import tk.mybatis.mapper.common.SqlServerMapper;
public interface MyMapper<T> extends Mapper<T> {
//TODO
//FIXME 特别注意，该接口不能被扫描到，否则会出错
}
Mapper.java 文件
import java.util.List;
import com.platform.entity.MrMsgRecord;
import com.platform.utils.MyMapper;
public interface MrMsgRecordMapper extends MyMapper<MrMsgRecord> {
/**
* 根据条件查询，主键倒序排序
*/
List<MrMsgRecord> selectByQuery(MrMsgRecord mrMsgRecord);
}
model 文件
import java.io.Serializable;
import java.util.Date;
import javax.persistence.*;
import lombok.Data;
import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import tk.mybatis.mapper.annotation.KeySql;
@ApiModel
@Data
@Table(name = "mr_msg_record")
public class MrMsgRecord implements Serializable {
private static final long serialVersionUID = 1L;
// 这两个注解是为了sqlserver 可以自增、获取自增的 id 值
@KeySql(useGeneratedKeys = true)
@Column(insertable=false)
private Long mrId;
@ApiModelProperty(value = "创建时间")
@Column(name = "mr_create_time")
private Date mrCreateTime;
@ApiModelProperty(value = "(接收者ID)指向用户表 外键")
@Column(name = "mr_target_id")
private String mrTargetId;
@ApiModelProperty(value = "聊天信息")
@Column(name = "mr_msg_body")
private String mrMsgBody;
@Id // 这个是代表这个字段是主键，多个 @Id 代表多个主键
@ApiModelProperty(value = "(发送者ID)指向用户表 外键")
@Column(name = "mr_from_id")
private String mrFromId;
@Id // 这个是代表这个字段是主键，多个 @Id 代表多个主键
@ApiModelProperty(value = "")
@Column(name = "mr_code")
private String mrCode;
}
// 注意：没有 @Id 则默认所有字段都是主键
Mapper.xml 文件
<?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.platform.dao.MrMsgRecordMapper">
<resultMap type="com.platform.entity.MrMsgRecord" id="mrMsgRecordMap">
<result property="mrId" column="mr_id"/>
<result property="mrCreateTime" column="mr_create_time"/>
<result property="mrTargetId" column="mr_target_id"/>
<result property="mrMsgBody" column="mr_msg_body"/>
<result property="mrFromId" column="mr_from_id"/>
<result property="mrCode" column="mr_code"/>
</resultMap>
<select id="selectByQuery" resultMap="mrMsgRecordMap">
select * from mr_msg_record
<where>
<if test="mrId != null and mrId != ''">
and mr_id = #{ mrId }
</if>
<if test="mrCreateTime != null ">
and mr_create_time = #{ mrCreateTime }
</if>
<if test="mrTargetId != null and mrTargetId != ''">
and mr_target_id = #{ mrTargetId }
</if>
<if test="mrMsgBody != null and mrMsgBody != ''">
and mr_msg_body = #{ mrMsgBody }
</if>
<if test="mrFromId != null and mrFromId != ''">
and mr_from_id = #{ mrFromId }
</if>
<if test="mrCode != null and mrCode != ''">
and mr_code = #{ mrCode }
</if>
</where>
order by mr_id desc
</select>
</mapper>