自动填充时间

• 官方文档

• 参考

• 指定字段的填充方式

public enum FieldFill {
    /**
     * 默认不处理
     */
    DEFAULT,
    /**
     * 插入填充字段
     */
    INSERT,
    /**
     * 更新填充字段
     */
    UPDATE,
    /**
     * 插入和更新填充字段
     */
    INSERT_UPDATE
}

• 实体类

@Data
@EqualsAndHashCode(callSuper = false)
@Accessors(chain = true)
@TableName("book")
public class Book implements Serializable {

    private static final long serialVersionUID = 1l;

    @TableId(value = "id", type = IdType.ASSIGN_UUID)    // 自动生成不含中划线的 UUID 作为主键
    private String id;

    @TableField(value = "created", fill = FieldFill.INSERT)    // MyBatis-Plus设置自动填充时间
    private Date created;

    @TableField(value = "updated", fill = FieldFill.INSERT_UPDATE)    // 自动更新时间
    private Date updated;

    @TableField(value="bookname", fill = FieldFill.INSERT_UPDATE)
    private String bookname;

}

• 填充器

@Slf4j
@Component
public class MyMetaObjectHandler implements MetaObjectHandler {

    /**
     * 执行插入操作时，如果时间字段为null，则自动填充
     * @param metaObject
     */
    @Override
    public void insertFill(MetaObject metaObject) {
        this.strictInsertFill(metaObject, "bookname", String.class, "红楼梦");
        this.setFieldValByName("created",new Date(),metaObject);
        this.setFieldValByName("updated",new Date(),metaObject);
    }

    /**
     * 执行修改操作时，如果时间字段为null，则自动填充
     * @param metaObject
     */
    @Override
    public void updateFill(MetaObject metaObject) {
        this.setFieldValByName("updated",new Date(),metaObject);
    }

}

• 测试

@RestController
@RequestMapping("/test")
public class TestController {

    @Autowired
    private UserMapper userMapper;

    @Autowired
    private BookMapper bookMapper;

    /**
     * 向book表插入数据
     * INSERT INTO book ( id, created, updated, bookname ) VALUES ( ?, ?, ?, ? )
     * a8b00085b1277972a690465f3dc35067(String), 2022-07-21 11:38:40.231(Timestamp), 2022-07-21 11:38:40.231(Timestamp), 红楼梦(String)
     */
    @RequestMapping("/test1")
    @ResponseBody
    public String test1(){
        bookMapper.insert(new Book());
        return "success";
    }

    /**
     * 修改1条数据
     * UPDATE book SET updated=?, bookname=? WHERE id=?
     * 2022-07-21 11:38:44.632(Timestamp), 西游记(String), 1(String)
     */
    @RequestMapping("/test2")
    @ResponseBody
    public String test2(){
        Book book = new Book();
        book.setId("1");
        book.setBookname("西游记");
        bookMapper.updateById(book);
        return "success";
    }

}