【Mabatis-Plus】MP相关使用

Mon, 06 Jul 2026 00:00:00 +0000

使用方法

以blog为例mapper需要继承BaseMapper

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public interface BlogMapper extends BaseMapper<Blog> {
 void incrLiked(@Param("id") Long id, @Param("num") int num);
}

ervice中需要继承 IService 这个IService中

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public interface IBlogService extends IService<Blog> {

 Result queryBlogById(Long id);
 Result queryHotBlog(Integer current);
 Result likeBlog(Long id);
 Result queryBlogLikes(Long blogId);

 Result saveBlog(Blog blog);

 /**
 * 滚动分页查询当前用户收件箱（关注博主推送的博客）
 * 基于 Redis ZSet 的 score（时间戳）倒序分页，解决传统分页在 Feed 流中数据错位的问题
 *
 * @param lastId 上一次查询返回的最小时间戳，作为本次查询的上界（首次传当前时间+1）
 * @param offset 上一次查询结果中与最小时间戳相等的元素个数，用于跳过重复数据
 * @return 包含 list（博客列表）、minTime（本次最小时间戳）、offset（本次偏移量）的结果
 */
 Result queryBlogOfFollow(Long lastId, Integer offset);
}

IService中会继承IRepository接口这个接口中有默认方法，有增删改查分页查询等封装好的函数

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public interface IService<T> extends IRepository<T> {
 @Transactional(
 rollbackFor = {Exception.class}
 )
 default boolean saveBatch(Collection<T> entityList) {
 return this.saveBatch(entityList, 1000);
 }

 @Transactional(
 rollbackFor = {Exception.class}
 )
 default boolean saveOrUpdateBatch(Collection<T> entityList) {
 return this.saveOrUpdateBatch(entityList, 1000);
 }

 @Transactional(
 rollbackFor = {Exception.class}
 )
 default boolean removeBatchByIds(Collection<?> list) {
 return this.removeByIds(list);
 }

 @Transactional(
 rollbackFor = {Exception.class}
 )
 default boolean updateBatchById(Collection<T> entityList) {
 return this.updateBatchById(entityList, 1000);
 }
}

Mabatis-Plus与Mabatis的区别

Mabatis-Plus分页查询

方法一：使用pagehelper

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<dependency>
 <groupId>com.github.pagehelper</groupId>
 <artifactId>pagehelper-spring-boot-starter</artifactId>
 <version>1.4.6</version>
</dependency>

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PageHelper.startPage(current, size);

方法二：使用page

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public Result<PageResult> getPageEmployee(EmployeePageQueryDTO employeePageQueryDTO) {
// 分页对象
Page<Employee> page = new Page<>(employeePageQueryDTO.getPage(), employeePageQueryDTO.getPageSize());
// 查询条件 wrapper 用于构造条件查询
LambdaQueryWrapper<Employee> wrapper = new LambdaQueryWrapper<>();
wrapper.like(employeePageQueryDTO.getName() != null, Employee::getName, employeePageQueryDTO.getName())
.orderByDesc(Employee::getCreateTime);

// 执行分页
Page<Employee> pageData = this.page(page, wrapper);

PageResult pageResult = new PageResult(pageData.getTotal(), pageData.getRecords());
return Result.success(pageResult);
}

解决insert和update中字段填充

MetaObjectHandler

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@Component
public class MyMetaObjectHandler implements MetaObjectHandler {

 @Override
 public void insertFill(MetaObject metaObject) {
 this.strictInsertFill(metaObject, "createTime", LocalDateTime.class, LocalDateTime.now());
 this.strictInsertFill(metaObject, "updateTime", LocalDateTime.class, LocalDateTime.now());
 this.strictInsertFill(metaObject, "createUser", Long.class, BaseContext.getCurrentId());
 this.strictInsertFill(metaObject, "updateUser", Long.class, BaseContext.getCurrentId());
 }

 @Override
 public void updateFill(MetaObject metaObject) {
 this.strictUpdateFill(metaObject, "updateTime", LocalDateTime.class, LocalDateTime.now());
 this.strictUpdateFill(metaObject, "updateUser", Long.class, BaseContext.getCurrentId());
 }
}

employee实体

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@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
@TableName("employee")
public class Employee implements Serializable {

 private static final long serialVersionUID = 1L;

 @TableId(type = IdType.AUTO)
 private Long id;

 private String username;

 private String name;

 private String password;

 private String phone;

 private String sex;

 private String idNumber;

 private Integer status;

 //@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
 @TableField(fill = FieldFill.INSERT)
 private LocalDateTime createTime;

 //@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
 @TableField(fill = FieldFill.INSERT_UPDATE)
 private LocalDateTime updateTime;

 @TableField(fill = FieldFill.INSERT)
 private Long createUser;

 @TableField(fill = FieldFill.INSERT_UPDATE)
 private Long updateUser;

}

MyBatis-Plus on muioo blog

【Mabatis-Plus】MP相关使用

使用方法

Mabatis-Plus与Mabatis的区别

Mabatis-Plus分页查询

解决insert和update中字段填充