如果你準(zhǔn)備做一個(gè)“智能課程學(xué)習(xí)系統(tǒng)”的項(xiàng)目無(wú)論是用于畢業(yè)設(shè)計(jì)、課程設(shè)計(jì)還是作為 Java 全棧能力的練手作品我的第一個(gè)建議是不要急著寫(xiě)代碼先把業(yè)務(wù)閉環(huán)想清楚。很多類(lèi)似項(xiàng)目最后“看起來(lái)都做完了”但數(shù)據(jù)庫(kù)一打開(kāi)就露餡課程表是課程表用戶(hù)表是用戶(hù)表中間沒(méi)有任何一條數(shù)據(jù)能回答“這個(gè)用戶(hù)到底學(xué)了多少、學(xué)到了哪里”。這樣的系統(tǒng)跑起來(lái)之后除了能在頁(yè)面上增刪改查既談不上學(xué)習(xí)管理也做不了個(gè)性化推薦最后只剩一個(gè)空殼。本文采用 SpringBoot3 Vue3 MySQL 的組合圍繞一套課程學(xué)習(xí)系統(tǒng)最常見(jiàn)的核心鏈路來(lái)展開(kāi)用戶(hù)登錄學(xué)習(xí)、章節(jié)進(jìn)度上報(bào)、課程進(jìn)度統(tǒng)計(jì)、基于標(biāo)簽的課程推薦、后臺(tái)課程維護(hù)。文章會(huì)給出可直接復(fù)制的數(shù)據(jù)庫(kù)腳本、后端接口、前端聯(lián)調(diào)代碼也會(huì)把新手最容易踩的幾個(gè)坑單獨(dú)拿出來(lái)講清楚。閱讀完本文你至少能獲得三樣?xùn)|西一套結(jié)構(gòu)清晰的數(shù)據(jù)庫(kù)表設(shè)計(jì)一套能處理學(xué)習(xí)進(jìn)度的 Spring Boot 3 后端接口一段真正能跑通聯(lián)調(diào)的 Vue3 前端代碼。1. 這類(lèi)項(xiàng)目最常見(jiàn)的失敗點(diǎn)把 CRUD 當(dāng)成全部幾乎所有初學(xué)者做的管理類(lèi)項(xiàng)目到最后都會(huì)變成 “CRUD 四件套”新增、刪除、修改、查詢(xún)。課程學(xué)習(xí)系統(tǒng)如果只做到這一步那它和“商品管理系統(tǒng)”沒(méi)有本質(zhì)區(qū)別也無(wú)法在答辯或面試中體現(xiàn)出你的建模能力。真正的學(xué)習(xí)類(lèi)系統(tǒng)和普通管理系統(tǒng)的差異在于你需要持續(xù)記錄用戶(hù)的行為狀態(tài)并根據(jù)狀態(tài)產(chǎn)生新的業(yè)務(wù)判斷。以“學(xué)習(xí)進(jìn)度”為例它不是一個(gè)簡(jiǎn)單字段而是一連串問(wèn)題用戶(hù)打開(kāi)了一個(gè)章節(jié)學(xué)到了第幾秒這個(gè)章節(jié)有沒(méi)有學(xué)完怎么定義“學(xué)完”一個(gè)課程有多個(gè)章節(jié)課程整體進(jìn)度怎么聚合計(jì)算用戶(hù)上次學(xué)到一半下次打開(kāi)課程是否應(yīng)該繼續(xù)這些問(wèn)題看似基礎(chǔ)但如果一開(kāi)始不設(shè)計(jì)好后面全都要返工。更常見(jiàn)的問(wèn)題是權(quán)限缺失。很多項(xiàng)目把管理員功能和普通用戶(hù)功能放在一起任何人知道接口地址就能刪除課程、改學(xué)習(xí)記錄。這在單機(jī)演示時(shí)沒(méi)問(wèn)題但一旦寫(xiě)到簡(jiǎn)歷上面試官大概率會(huì)追問(wèn)你怎么保證一個(gè)用戶(hù)不能修改別人的學(xué)習(xí)記錄所以這個(gè)系統(tǒng)的設(shè)計(jì)重點(diǎn)不在前端特效也不在框架選擇而在于把課程內(nèi)容與學(xué)習(xí)記錄之間的關(guān)系表設(shè)計(jì)正確把進(jìn)度上報(bào)接口做成可靠且冪等把推薦功能建立在真實(shí)學(xué)習(xí)行為之上而不是單純寫(xiě)死。只有先建立這個(gè)判斷下面所有代碼才有意義。2. 技術(shù)選型與系統(tǒng)邊界為什么是 SpringBoot3 Vue3 MySQL現(xiàn)在的 Java 全棧項(xiàng)目很多會(huì)直接上微服務(wù)或者把 Redis、MQ、ES 全部塞進(jìn)來(lái)。但針對(duì)課程學(xué)習(xí)系統(tǒng)這種業(yè)務(wù)盲目引入分布式組件只會(huì)讓維護(hù)成本遠(yuǎn)超收益。合理的做法是先用單體架構(gòu)把業(yè)務(wù)跑通再根據(jù)真實(shí)瓶頸引入中間件。這套系統(tǒng)的技術(shù)選型定位如下技術(shù)組件作用選擇理由Spring Boot 3后端基礎(chǔ)框架快速構(gòu)建 REST API內(nèi)置依賴(lài)管理和自動(dòng)裝配Vue 3 Vite前端開(kāi)發(fā)框架組合式 API 更適合復(fù)雜頁(yè)面交互開(kāi)發(fā)體驗(yàn)好MySQL 8.x關(guān)系型數(shù)據(jù)庫(kù)課程、用戶(hù)、學(xué)習(xí)記錄之間存在明確關(guān)系適合用 MySQL 存儲(chǔ)MyBatis-PlusORM 框架減少單表 CRUD 代碼專(zhuān)注業(yè)務(wù)邏輯Maven項(xiàng)目管理工具Java 項(xiàng)目最常見(jiàn)的依賴(lài)管理方式在 Spring Boot 3 中需要注意一個(gè)關(guān)鍵點(diǎn)它基于 Jakarta EE 9因此原來(lái) Spring Boot 2 中使用的javax.servlet、javax.validation等包名在 Spring Boot 3 中已經(jīng)變?yōu)閖akarta.servlet、jakarta.validation。如果你搜索資料時(shí)看到大量老代碼第一件要做的事就是檢查包名否則即使照抄也一樣編譯失敗。系統(tǒng)功能邊界建議控制在以下模塊模塊功能說(shuō)明用戶(hù)模塊登錄、注冊(cè)、個(gè)人信息維護(hù)后續(xù)可擴(kuò)展 Token 鑒權(quán)課程模塊課程列表、課程詳情、課程章節(jié)展示學(xué)習(xí)模塊學(xué)習(xí)進(jìn)度上報(bào)、課程總進(jìn)度計(jì)算、繼續(xù)學(xué)習(xí)定位收藏模塊用戶(hù)收藏感興趣的課程標(biāo)簽與推薦模塊維護(hù)課程標(biāo)簽根據(jù)用戶(hù)學(xué)習(xí)歷史推薦同標(biāo)簽課程管理后臺(tái)課程上下架、章節(jié)管理、標(biāo)簽維護(hù)接下來(lái)分三步實(shí)現(xiàn)先設(shè)計(jì) MySQL 表結(jié)構(gòu)再寫(xiě) Spring Boot 3 后端最后寫(xiě) Vue3 前端頁(yè)面。3. MySQL 數(shù)據(jù)庫(kù)設(shè)計(jì)用學(xué)習(xí)記錄連接用戶(hù)與課程數(shù)據(jù)庫(kù)是整個(gè)系統(tǒng)最值得認(rèn)真投入的部分。表結(jié)構(gòu)如果設(shè)計(jì)錯(cuò)后續(xù)代碼怎么寫(xiě)都別扭。3.1 核心表結(jié)構(gòu)總覽本系統(tǒng)至少需要以下核心表表名說(shuō)明sys_user系統(tǒng)用戶(hù)表course課程表course_chapter課程章節(jié)表learning_record學(xué)習(xí)進(jìn)度記錄表course_favorite課程收藏表tag標(biāo)簽表course_tag課程標(biāo)簽關(guān)聯(lián)表其中最關(guān)鍵的是learning_record表。它負(fù)責(zé)記錄“哪個(gè)用戶(hù)在哪個(gè)課程的哪個(gè)章節(jié)學(xué)到了第幾秒”。3.2 建表 SQL 示例下面的 SQL 可以直接在 MySQL 8.x 中執(zhí)行。先創(chuàng)建數(shù)據(jù)庫(kù)然后創(chuàng)建各張表。CREATE DATABASE IF NOT EXISTS smart_course DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci; USE smart_course; CREATE TABLE IF NOT EXISTS sys_user ( id BIGINT PRIMARY KEY AUTO_INCREMENT COMMENT 用戶(hù)ID, username VARCHAR(50) NOT NULL COMMENT 登錄賬號(hào), password VARCHAR(100) NOT NULL COMMENT 密碼生產(chǎn)環(huán)境必須加密存儲(chǔ), nickname VARCHAR(50) DEFAULT COMMENT 昵稱(chēng), avatar VARCHAR(255) DEFAULT COMMENT 頭像地址, status TINYINT DEFAULT 1 COMMENT 狀態(tài)1正常 0禁用, create_time DATETIME DEFAULT CURRENT_TIMESTAMP COMMENT 創(chuàng)建時(shí)間, UNIQUE KEY uk_username (username) ) ENGINE InnoDB COMMENT 系統(tǒng)用戶(hù)表; CREATE TABLE IF NOT EXISTS course ( id BIGINT PRIMARY KEY AUTO_INCREMENT COMMENT 課程ID, title VARCHAR(100) NOT NULL COMMENT 課程標(biāo)題, subtitle VARCHAR(200) DEFAULT COMMENT 副標(biāo)題, cover_url VARCHAR(255) DEFAULT COMMENT 封面圖, price DECIMAL(10, 2) DEFAULT 0.00 COMMENT 課程價(jià)格, original_price DECIMAL(10, 2) DEFAULT 0.00 COMMENT 原價(jià)用于展示劃線(xiàn)價(jià), difficulty TINYINT DEFAULT 1 COMMENT 難度1入門(mén) 2進(jìn)階 3高級(jí), status TINYINT DEFAULT 0 COMMENT 狀態(tài)0未上架 1已上架, view_count INT DEFAULT 0 COMMENT 瀏覽量, deleted TINYINT DEFAULT 0 COMMENT 邏輯刪除0未刪除 1已刪除, create_time DATETIME DEFAULT CURRENT_TIMESTAMP COMMENT 創(chuàng)建時(shí)間, update_time DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT 更新時(shí)間 ) ENGINE InnoDB COMMENT 課程表; CREATE TABLE IF NOT EXISTS course_chapter ( id BIGINT PRIMARY KEY AUTO_INCREMENT COMMENT 章節(jié)ID, course_id BIGINT NOT NULL COMMENT 所屬課程ID, chapter_no INT NOT NULL COMMENT 章節(jié)序號(hào)從1開(kāi)始, title VARCHAR(150) NOT NULL COMMENT 章節(jié)標(biāo)題, video_url VARCHAR(255) DEFAULT COMMENT 視頻地址, duration_seconds INT DEFAULT 0 COMMENT 章節(jié)視頻時(shí)長(zhǎng)單位秒, create_time DATETIME DEFAULT CURRENT_TIMESTAMP COMMENT 創(chuàng)建時(shí)間, UNIQUE KEY uk_course_no (course_id, chapter_no) ) ENGINE InnoDB COMMENT 課程章節(jié)表; CREATE TABLE IF NOT EXISTS learning_record ( id BIGINT PRIMARY KEY AUTO_INCREMENT COMMENT 記錄ID, user_id BIGINT NOT NULL COMMENT 用戶(hù)ID, course_id BIGINT NOT NULL COMMENT 課程ID, chapter_id BIGINT NOT NULL COMMENT 章節(jié)ID, progress_seconds INT DEFAULT 0 COMMENT 已學(xué)習(xí)到的秒數(shù), duration_seconds INT DEFAULT 0 COMMENT 章節(jié)總時(shí)長(zhǎng)冗余存儲(chǔ)方便統(tǒng)計(jì), finished TINYINT DEFAULT 0 COMMENT 本章節(jié)是否學(xué)完0未完成 1完成, last_learn_time DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT 最后學(xué)習(xí)時(shí)間, UNIQUE KEY uk_user_chapter (user_id, chapter_id), KEY idx_user_course (user_id, course_id) ) ENGINE InnoDB COMMENT 學(xué)習(xí)進(jìn)度記錄表; CREATE TABLE IF NOT EXISTS course_favorite ( id BIGINT PRIMARY KEY AUTO_INCREMENT COMMENT 收藏ID, user_id BIGINT NOT NULL COMMENT 用戶(hù)ID, course_id BIGINT NOT NULL COMMENT 課程ID, create_time DATETIME DEFAULT CURRENT_TIMESTAMP COMMENT 收藏時(shí)間, UNIQUE KEY uk_user_course (user_id, course_id) ) ENGINE InnoDB COMMENT 課程收藏表; CREATE TABLE IF NOT EXISTS tag ( id BIGINT PRIMARY KEY AUTO_INCREMENT COMMENT 標(biāo)簽ID, tag_name VARCHAR(30) NOT NULL COMMENT 標(biāo)簽名, UNIQUE KEY uk_tag_name (tag_name) ) ENGINE InnoDB COMMENT 課程標(biāo)簽表; CREATE TABLE IF NOT EXISTS course_tag ( id BIGINT PRIMARY KEY AUTO_INCREMENT COMMENT 關(guān)聯(lián)ID, course_id BIGINT NOT NULL COMMENT 課程ID, tag_id BIGINT NOT NULL COMMENT 標(biāo)簽ID, UNIQUE KEY uk_course_tag (course_id, tag_id), KEY idx_tag_id (tag_id) ) ENGINE InnoDB COMMENT 課程標(biāo)簽關(guān)聯(lián)表;3.3 表結(jié)構(gòu)設(shè)計(jì)的關(guān)鍵點(diǎn)這里真正容易踩坑的地方是learning_record表的唯一索引。一個(gè)用戶(hù)反復(fù)學(xué)習(xí)同一個(gè)章節(jié)不應(yīng)該在表中產(chǎn)生多條歷史記錄。使用UNIQUE KEY uk_user_chapter (user_id, chapter_id)之后每次上報(bào)進(jìn)度時(shí)業(yè)務(wù)層只需要處理“插入”或“更新”兩種可能數(shù)據(jù)不會(huì)無(wú)限膨脹。course_chapter表中course_id chapter_no也設(shè)置了唯一索引目的是避免同一個(gè)課程出現(xiàn)兩個(gè)第 3 章。還有一個(gè)很實(shí)用的設(shè)計(jì)是course.deleted字段。在管理后臺(tái)“刪除課程”時(shí)不建議使用物理刪除因?yàn)闅v史學(xué)習(xí)記錄可能還引用該課程。采用邏輯刪除字段之后數(shù)據(jù)仍然保留但業(yè)務(wù)查詢(xún)會(huì)自動(dòng)排除MyBatis-Plus 通過(guò)TableLogic注解即可支持。4. SpringBoot3 后端工程搭建4.1 創(chuàng)建工程與引入依賴(lài)后端工程可以通過(guò) IDEA 的 Spring Initializr 創(chuàng)建也可以直接手工創(chuàng)建 Maven 工程。核心依賴(lài)如下示例版本請(qǐng)以你實(shí)際初始化出的版本為準(zhǔn)parent groupIdorg.springframework.boot/groupId artifactIdspring-boot-starter-parent/artifactId version3.2.5/version relativePath/ /parent dependencies dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-starter-web/artifactId /dependency dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-starter-validation/artifactId /dependency dependency groupIdcom.baomidou/groupId artifactIdmybatis-plus-spring-boot3-starter/artifactId version3.5.7/version /dependency dependency groupIdcom.mysql/groupId artifactIdmysql-connector-j/artifactId scoperuntime/scope /dependency dependency groupIdorg.projectlombok/groupId artifactIdlombok/artifactId optionaltrue/optional /dependency dependency groupIdorg.springframework.boot/groupId artifactIdspring-boot-starter-test/artifactId scopetest/scope /dependency /dependencies這里需要特別提醒MyBatis-Plus 在 Spring Boot 3 下不能再使用老的mybatis-plus-boot-starter必須使用mybatis-plus-spring-boot3-starter否則會(huì)出現(xiàn)自動(dòng)配置不生效的問(wèn)題。4.2 配置文件src/main/resources/application.yml內(nèi)容如下server: port: 8080 spring: datasource: driver-class-name: com.mysql.cj.jdbc.Driver url: jdbc:mysql://localhost:3306/smart_course?useUnicodetruecharacterEncodingutf8useSSLfalseserverTimezoneAsia/ShanghaiallowPublicKeyRetrievaltrue username: root password: your_password mybatis-plus: configuration: map-underscore-to-camel-case: true log-impl: org.apache.ibatis.logging.stdout.StdOutImpl global-config: banner: false數(shù)據(jù)庫(kù)密碼請(qǐng)?zhí)鎿Q成你本機(jī)的 MySQL 密碼。allowPublicKeyRetrievaltrue是 MySQL 8 連接時(shí)經(jīng)常需要配置的參數(shù)否則可能報(bào)Public Key Retrieval is not allowed錯(cuò)誤。4.3 統(tǒng)一返回結(jié)構(gòu)與異常處理后端接口如果格式不統(tǒng)一前端在 axios 攔截器里就非常難處理。建議從第一步就定義統(tǒng)一響應(yīng)結(jié)構(gòu)。package com.example.smartcourse.common; import lombok.Data; Data public class ResultT { private Integer code; private String message; private T data; public static T ResultT success(T data) { ResultT result new Result(); result.setCode(0); result.setMessage(success); result.setData(data); return result; } public static T ResultT error(String message) { ResultT result new Result(); result.setCode(500); result.setMessage(message); return result; } }再定義一個(gè)業(yè)務(wù)異常類(lèi)用于處理“參數(shù)不合法、數(shù)據(jù)不存在”等業(yè)務(wù)錯(cuò)誤。package com.example.smartcourse.common; public class BizException extends RuntimeException { public BizException(String message) { super(message); } }最后寫(xiě)一個(gè)全局異常處理器把異常轉(zhuǎn)換為統(tǒng)一結(jié)構(gòu)避免把堆棧直接拋給前端。package com.example.smartcourse.common; import lombok.extern.slf4j.Slf4j; import org.springframework.web.bind.annotation.ExceptionHandler; import org.springframework.web.bind.annotation.RestControllerAdvice; Slf4j RestControllerAdvice public class GlobalExceptionHandler { ExceptionHandler(BizException.class) public ResultVoid handleBizException(BizException e) { return Result.error(e.getMessage()); } ExceptionHandler(Exception.class) public ResultVoid handleException(Exception e) { log.error(系統(tǒng)異常, e); return Result.error(系統(tǒng)繁忙請(qǐng)稍后重試); } }統(tǒng)一返回結(jié)果之后前端只需要判斷code是否為 0不用每個(gè)接口單獨(dú)解析不同的字段結(jié)構(gòu)。5. 核心業(yè)務(wù)實(shí)現(xiàn)學(xué)習(xí)進(jìn)度上報(bào)與課程進(jìn)度統(tǒng)計(jì)學(xué)習(xí)進(jìn)度是整套系統(tǒng)的核心。下面以“用戶(hù)學(xué)習(xí)某個(gè)章節(jié)后上報(bào)當(dāng)前播放秒數(shù)”為例寫(xiě)完整實(shí)現(xiàn)。5.1 實(shí)體類(lèi)先創(chuàng)建Course實(shí)體對(duì)應(yīng)課程表。package com.example.smartcourse.entity; import com.baomidou.mybatisplus.annotation.IdType; import com.baomidou.mybatisplus.annotation.TableId; import com.baomidou.mybatisplus.annotation.TableLogic; import com.baomidou.mybatisplus.annotation.TableName; import lombok.Data; import java.math.BigDecimal; import java.time.LocalDateTime; Data TableName(course) public class Course { TableId(type IdType.AUTO) private Long id; private String title; private String subtitle; private String coverUrl; private BigDecimal price; private BigDecimal originalPrice; private Integer difficulty; private Integer status; private Integer viewCount; TableLogic private Integer deleted; private LocalDateTime createTime; private LocalDateTime updateTime; }再創(chuàng)建LearningRecord實(shí)體。package com.example.smartcourse.entity; import com.baomidou.mybatisplus.annotation.IdType; import com.baomidou.mybatisplus.annotation.TableId; import com.baomidou.mybatisplus.annotation.TableName; import lombok.Data; import java.time.LocalDateTime; Data TableName(learning_record) public class LearningRecord { TableId(type IdType.AUTO) private Long id; private Long userId; private Long courseId; private Long chapterId; private Integer progressSeconds; private Integer durationSeconds; private Boolean finished; private LocalDateTime lastLearnTime; }5.2 MapperMapper 層繼承 MyBatis-Plus 的BaseMapper基礎(chǔ)單表方法會(huì)自動(dòng)生成。package com.example.smartcourse.mapper; import com.baomidou.mybatisplus.core.mapper.BaseMapper; import com.example.smartcourse.entity.LearningRecord; import org.apache.ibatis.annotations.Mapper; Mapper public interface LearningRecordMapper extends BaseMapperLearningRecord { }課程 Mapper 類(lèi)似但后面做推薦查詢(xún)時(shí)會(huì)額外增加一個(gè)自定義方法。package com.example.smartcourse.mapper; import com.baomidou.mybatisplus.core.mapper.BaseMapper; import com.example.smartcourse.entity.Course; import org.apache.ibatis.annotations.Mapper; import org.apache.ibatis.annotations.Param; import org.apache.ibatis.annotations.Select; import java.util.List; Mapper public interface CourseMapper extends BaseMapperCourse { Select( SELECT c.* FROM course c WHERE c.status 1 AND c.deleted 0 AND c.id NOT IN ( SELECT course_id FROM learning_record WHERE user_id #{userId} ) AND c.id IN ( SELECT DISTINCT ct.course_id FROM course_tag ct WHERE ct.tag_id IN ( SELECT DISTINCT ct2.tag_id FROM course_tag ct2 JOIN learning_record lr ON lr.course_id ct2.course_id WHERE lr.user_id #{userId} ) ) ORDER BY ( SELECT COUNT(1) FROM course_tag ct3 WHERE ct3.course_id c.id AND ct3.tag_id IN ( SELECT DISTINCT ct2.tag_id FROM course_tag ct2 JOIN learning_record lr ON lr.course_id ct2.course_id WHERE lr.user_id #{userId} ) ) DESC, c.view_count DESC LIMIT #{limit} ) ListCourse recommendByUser(Param(userId) Long userId, Param(limit) int limit); }5.3 Service 層實(shí)現(xiàn)冪等進(jìn)度上報(bào)提交進(jìn)度請(qǐng)求時(shí)前端會(huì)傳用戶(hù) ID、課程 ID、章節(jié) ID、當(dāng)前播放秒數(shù)、章節(jié)總時(shí)長(zhǎng)。Service 層要做的事很簡(jiǎn)單有記錄就更新沒(méi)有記錄就插入。但這里要加一個(gè)判斷如果新的進(jìn)度比舊進(jìn)度小說(shuō)明可能是一次遲到的舊請(qǐng)求不應(yīng)該把它覆蓋成更小的值。package com.example.smartcourse.service; import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper; import com.example.smartcourse.common.BizException; import com.example.smartcourse.dto.ProgressSubmitRequest; import com.example.smartcourse.entity.CourseChapter; import com.example.smartcourse.entity.LearningRecord; import com.example.smartcourse.mapper.CourseChapterMapper; import com.example.smartcourse.mapper.LearningRecordMapper; import lombok.RequiredArgsConstructor; import org.springframework.stereotype.Service; import org.springframework.transaction.annotation.Transactional; import java.math.BigDecimal; import java.math.RoundingMode; Service RequiredArgsConstructor public class LearningRecordService { private static final double FINISH_RATIO 0.9; private final LearningRecordMapper learningRecordMapper; private final CourseChapterMapper courseChapterMapper; Transactional(rollbackFor Exception.class) public LearningRecord submitProgress(ProgressSubmitRequest request) { if (request.getProgressSeconds() request.getDurationSeconds()) { throw new BizException(學(xué)習(xí)進(jìn)度不能超過(guò)章節(jié)總時(shí)長(zhǎng)); } LearningRecord record learningRecordMapper.selectOne( new LambdaQueryWrapperLearningRecord() .eq(LearningRecord::getUserId, request.getUserId()) .eq(LearningRecord::getChapterId, request.getChapterId()) ); boolean finished request.getProgressSeconds() request.getDurationSeconds() * FINISH_RATIO; if (record null) { record new LearningRecord(); record.setUserId(request.getUserId()); record.setCourseId(request.getCourseId()); record.setChapterId(request.getChapterId()); record.setProgressSeconds(request.getProgressSeconds()); record.setDurationSeconds(request.getDurationSeconds()); record.setFinished(finished); learningRecordMapper.insert(record); } else { if (request.getProgressSeconds() record.getProgressSeconds()) { record.setProgressSeconds(request.getProgressSeconds()); record.setDurationSeconds(request.getDurationSeconds()); if (!Boolean.TRUE.equals(record.getFinished()) finished) { record.setFinished(true); } learningRecordMapper.updateById(record); } } return record; } public double getCourseProgress(Long userId, Long courseId) { Long totalChapters courseChapterMapper.selectCount( new LambdaQueryWrapperCourseChapter() .eq(CourseChapter::getCourseId, courseId) ); if (totalChapters null || totalChapters 0) { return 0D; } Long finishedChapters learningRecordMapper.selectCount( new LambdaQueryWrapperLearningRecord() .eq(LearningRecord::getUserId, userId) .eq(LearningRecord::getCourseId, courseId) .eq(LearningRecord::getFinished, true) ); return BigDecimal.valueOf(finishedChapters) .multiply(BigDecimal.valueOf(100)) .divide(BigDecimal.valueOf(totalChapters), 1, RoundingMode.HALF_UP) .doubleValue(); } }這里定義FINISH_RATIO 0.9意思是用戶(hù)的播放進(jìn)度達(dá)到章節(jié)總時(shí)長(zhǎng)的 90%就認(rèn)為該章節(jié)學(xué)完。這個(gè)閾值可以根據(jù)業(yè)務(wù)需要調(diào)整也可以改成“必須看到最后一秒才算學(xué)完”。LearningRecord.finished使用Boolean類(lèi)型當(dāng)已經(jīng)完成時(shí)不會(huì)因?yàn)楹罄m(xù)一次較小進(jìn)度的上報(bào)而變回未完成這是防止?fàn)顟B(tài)回退的關(guān)鍵。5.4 DTO 與 Controller創(chuàng)建ProgressSubmitRequest作為參數(shù)接收對(duì)象并做參數(shù)校驗(yàn)。package com.example.smartcourse.dto; import jakarta.validation.constraints.Min; import jakarta.validation.constraints.NotNull; import lombok.Data; Data public class ProgressSubmitRequest { NotNull(message 用戶(hù)ID不能為空) private Long userId; NotNull(message 課程ID不能為空) private Long courseId; NotNull(message 章節(jié)ID不能為空) private Long chapterId; NotNull(message 播放進(jìn)度不能為空) Min(value 0, message 播放進(jìn)度不能小于0) private Integer progressSeconds; NotNull(message 章節(jié)總時(shí)長(zhǎng)不能為空) Min(value 1, message 章節(jié)總時(shí)長(zhǎng)必須大于0) private Integer durationSeconds; }Controller 提供兩個(gè)接口一個(gè)是上報(bào)進(jìn)度一個(gè)是查詢(xún)課程總進(jìn)度。package com.example.smartcourse.controller; import com.example.smartcourse.common.Result; import com.example.smartcourse.dto.ProgressSubmitRequest; import com.example.smartcourse.entity.LearningRecord; import com.example.smartcourse.service.LearningRecordService; import jakarta.validation.Valid; import lombok.RequiredArgsConstructor; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.PostMapping; import org.springframework.web.bind.annotation.RequestBody; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.RestController; RestController RequestMapping(/api/learning) RequiredArgsConstructor public class LearningRecordController { private final LearningRecordService learningRecordService; PostMapping(/progress) public ResultLearningRecord submitProgress(RequestBody Valid ProgressSubmitRequest request) { return Result.success(learningRecordService.submitProgress(request)); } GetMapping(/course-progress) public ResultDouble getCourseProgress(RequestParam Long userId, RequestParam Long courseId) { return Result.success(learningRecordService.getCourseProgress(userId, courseId)); } }啟動(dòng)類(lèi)需要增加MapperScan注解否則 Mapper 不會(huì)自動(dòng)掃描。package com.example.smartcourse; import org.mybatis.spring.annotation.M