项目改造操作（图书管理系统为例）

1. {
2. "status": 200,//状态码
3. "msg": "获取成功",//响应信息
4. "data": [//返回数据==》所有的读者编号
5. "65125544"
6.   ],
7. "map": {}
8. }

1. @GetMapping("getAllCardNumber")
2. public R getAllCardNumber() {
3.        List<Long> list=usersService.getAllCardNumber();
4. return R.ok(list,"获取成功");
5.     }

List<Long> getAllCardNumber();

1. @Override
2. public List<Long> getAllCardNumber() {
3. 
4.         List<Users> list = this.list();
5.         List<Long> collect = list.stream().map(item -> {
6. Long cardNumber = item.getCardNumber();
7. return cardNumber;
8.         }).collect(Collectors.toList());
9. return collect;
10. 
11.     }

1. {
2. "status": 200,//状态码
3. "msg": "获取成功",//响应信息
4. "data": [//返回数据==》未被借阅的书籍编号
5. "65125544"
6.   ],
7. "map": {}
8. }

1. @GetMapping("getAllNotBorrowBook")
2. public R getAllNotBorrowBook() {
3.         List<String> list= booksService.getAllNotBorrowBook();
4. return R.ok(list,"获取成功");
5. 
6.     }

List<String> getAllNotBorrowBook();

1. @Override
2. public List<String> getAllNotBorrowBook() {
3.         List<Books> list = this.list();
4.         List<String> collect = list.stream().filter(item -> {
5. if ("已借出".equals(item.getBookStatus())) {
6. return false;
7.             } else {
8. return true;
9.             }
10.         }).map(item -> {
11. return item.getBookNumber();
12.         }).collect(Collectors.toList());
13. return  collect;
14.     }

1. {
2. "status": 200,//状态码
3. "msg": "获取成功",//响应信息
4. "data":true,//成功还是失败的响应
5. "map": {}
6. }

1. /**
2.      * 借书
3.      * @param booksBorrowDTO
4.      * @return
5.      */
6. @PostMapping("borrowBook")
7. public R borrowBookByCardNumberAndBookNumber(@RequestBody BooksBorrowDTO booksBorrowDTO) {
8.         System.out.println("1234");
9. boolean b= booksBorrowService.borrowBook(booksBorrowDTO);
10. if (b==false){
11. return R.error("借书失败（请校验数据，IBSN或借书凭证出错，或者该书已借出异常）");
12.         }else {
13. return R.ok("借书成功");
14.         }
15. 
16.     }

boolean borrowBook(BooksBorrowDTO booksBorrowDTO);

1. @Override
2. @Transactional(rollbackFor = Exception.class)
3. public boolean borrowBook(BooksBorrowDTO booksBorrowDTO) {
4. /**
5.          *  1.接受前端请求中的参数(借阅证号、图书编号、借阅时间)
6.          *  2.先根据借阅证号查询是否有此用户存在，不存在直接返回错误信息
7.          *  3.用户存在，根据图书编号查询图书表，查询是否有图书存在并且该图书的状态是未借出
8.          *  4.用户存在，图书存在，且未借出 说明可以借出该图书
9.          *  5.#获取用户的规则编号#，根据编号查询出规则(判断空),获取规则的可借天数
10.          *  6.设置期限天数为当前时间+规则的可借天数 设置归还日期为空
11.          *  7.调用bookBorrow，进行插入记录
12.          *  8.如果插入成功，修改在图书表中对应图书编号的状态为已借出
13.          *  9.判断是否更新成功
14.          *  10.插入成功+更新成功，则返回请求状态码200和请求信息
15.          */
16. // 图书编号
17. Integer bookNumber = booksBorrowDTO.getBookNumber();
18. // 借阅证号
19. Long cardNumber = booksBorrowDTO.getCardNumber();
20. // 借阅时间
21. LocalDateTime borrowDate = booksBorrowDTO.getBorrowDate();
22.         LambdaQueryWrapper<Users> queryWrapper = new LambdaQueryWrapper<>();
23.         queryWrapper.eq(Users::getCardNumber, cardNumber);
24. Users users = usersMapper.selectOne(queryWrapper);
25. if (users == null) {
26. return false;
27.         }
28.         LambdaQueryWrapper<Books> queryWrapper1 = new LambdaQueryWrapper<>();
29.         queryWrapper1.eq(Books::getBookNumber, bookNumber);
30. Books book = booksMapper.selectOne(queryWrapper1);
31. if ((book == null) || (book.getBookStatus().equals(Constant.BOOKDISABLE))) {
32. return false;
33.         }
34. 
35. // 规则编号
36. Integer ruleNumber = users.getRuleNumber();
37.         LambdaQueryWrapper<BookRule> queryWrapper2 = new LambdaQueryWrapper<>();
38.         queryWrapper2.eq(BookRule::getBookRuleId, ruleNumber);
39. BookRule bookRule = bookRuleMapper.selectOne(queryWrapper2);
40. if (bookRule == null) {
41. return false;
42.         }
43. // 可借天数
44. Integer bookDays = bookRule.getBookDays();
45. LocalDateTime closeDate = borrowDate.plusDays(bookDays);
46. BooksBorrow booksBorrow1 = new BooksBorrow();
47.         booksBorrow1.setBorrowId(null);
48.         booksBorrow1.setBookNumber(bookNumber);
49.         booksBorrow1.setCardNumber(cardNumber);
50.         booksBorrow1.setBorrowDate(borrowDate);
51.         booksBorrow1.setCloseDate(closeDate);
52.         booksBorrow1.setReturnDate(null);
53. boolean flag = this.save(booksBorrow1);
54. if (!flag) {
55. return false;
56.         }
57.         book.setBookStatus(Constant.BOOKDISABLE);
58. int update = booksMapper.update(book, queryWrapper1);
59. if (update==0) {
60. return false;
61.         }
62. Violation violation = new Violation();
63.         BeanUtils.copyProperties(booksBorrow1, violation, "borrowId");
64.         violation.setViolationId(null);
65.         violation.setViolationMessage("");
66.         violation.setBookNumber(book.getBookNumber());
67.         violation.setViolationAdminId(booksBorrowDTO.getBookAdminId());
68. int save = violationMapper.insert(violation);
69. if (save==0) {
70. return false;
71.         }
72. return true;
73.     }

1. <el-menu-item index="borrowbook" @click="saveNavState('borrowbook')">
2. <i class="el-icon-collection"></i>
3. <span slo="title">借阅图书</span>
4. </el-menu-item>

import BorrowBook from '../components/BookManage/BorrowBook.vue'

{ path: '/borrowbook', component: BorrowBook },

1. <template>
2. <div class="borrowbook_container">
3. <div class="header"><p>借阅图书 </p></div>
4. <div class="banner">
5. 
6.     借阅证号:<br> <el-select v-model.number="borrowInfo.cardNumber"  placeholder="请选择借阅证号">
7. <el-option
8. v-for="item in cardNumbers"
9. :key="item"
10. :label="item"
11. :value="item">
12. </el-option>
13. </el-select>
14.    图书编号:<br> <el-select v-model.number="borrowInfo.bookNumber"  placeholder="请选择图书编号">
15. <el-option
16.