Java開發(fā)項目實戰(zhàn)案例與代碼詳解項目背景與需求分析一個現(xiàn)代化的電商平臺系統(tǒng)需要具備用戶管理、商品展示、購物車、訂單處理、支付集成、后臺管理等核心功能。本案例以Java語言為主，結合SpringBoot框架和MySQL數(shù)據(jù)庫，實現(xiàn)一個基礎但功能完整的電商平臺。項目采用前后端分離架構，前端使用Vue.js，后端基于SpringBoot開發(fā)RESTfulAPI接口。核心需求模塊1.用戶模塊：實現(xiàn)用戶注冊、登錄、個人信息管理、密碼修改等功能2.商品模塊：商品分類展示、商品搜索、商品詳情查看3.購物車模塊：添加商品到購物車、修改數(shù)量、刪除商品4.訂單模塊：生成訂單、訂單狀態(tài)管理、訂單歷史查看5.支付模塊：集成了模擬支付功能6.后臺管理模塊：用戶管理、商品管理、訂單管理技術選型與架構設計技術棧-后端：Java8+,SpringBoot2.5,SpringMVC,SpringDataJPA,MyBatis,Thymeleaf,Redis,Maven-前端：Vue.js3,ElementPlusUI組件庫,Axios-數(shù)據(jù)庫：MySQL8.0-緩存：Redis6.2-部署：Docker,Nginx架構設計系統(tǒng)采用分層架構設計：1.表現(xiàn)層：前端Vue.js應用，負責用戶界面和交互2.應用層：SpringBoot控制器，處理業(yè)務邏輯和API接口3.領域?qū)樱簶I(yè)務實體和業(yè)務邏輯4.數(shù)據(jù)訪問層：MyBatis或JPA實現(xiàn)數(shù)據(jù)持久化5.基礎設施層：數(shù)據(jù)庫、緩存、消息隊列等這種分層設計保證了系統(tǒng)的可維護性和可擴展性，同時也便于團隊協(xié)作開發(fā)。核心模塊實現(xiàn)詳解用戶模塊實現(xiàn)數(shù)據(jù)庫設計sqlCREATETABLEusers(idBIGINTAUTO_INCREMENTPRIMARYKEY,usernameVARCHAR(50)NOTNULLUNIQUE,passwordVARCHAR(100)NOTNULL,emailVARCHAR(100)NOTNULLUNIQUE,phoneVARCHAR(20),created_atTIMESTAMPDEFAULTCURRENT_TIMESTAMP,updated_atTIMESTAMPDEFAULTCURRENT_TIMESTAMPONUPDATECURRENT_TIMESTAMP,roleENUM('USER','ADMIN')DEFAULT'USER');用戶注冊與登錄使用SpringSecurity實現(xiàn)用戶認證和授權。java//SecurityConfig配置@EnableWebSecuritypublicclassSecurityConfigextendsWebSecurityConfigurerAdapter{@AutowiredprivateUserDetailsServiceuserDetailsService;@Overrideprotectedvoidconfigure(HttpSecurityhttp)throwsException{http.csrf().disable().authorizeRequests().antMatchers("/api/auth/").permitAll().antMatchers("/api/admin/").hasRole("ADMIN").anyRequest().authenticated().and().sessionManagement().sessionless().and().addFilterBefore(newJwtAuthenticationFilter(),UsernamePasswordAuthenticationFilter.class);}@Overrideprotectedvoidconfigure(AuthenticationManagerBuilderauth)throwsException{auth.userDetailsService(userDetailsService).passwordEncoder(newBCryptPasswordEncoder());}}java//用戶注冊服務@ServicepublicclassUserServiceimplementsUserDetailsService{@AutowiredprivateUserRepositoryuserRepository;@OverridepublicUserDetailsloadUserByUsername(Stringusername)throwsUsernameNotFoundException{Useruser=userRepository.findByUsername(username).orElseThrow(()->newUsernameNotFoundException("用戶不存在"));returnneworg.springframework.security.core.userdetails.User(user.getUsername(),user.getPassword(),getAuthorities(user));}publicList<SimpleGrantedAuthority>getAuthorities(Useruser){List<SimpleGrantedAuthority>authorities=newArrayList<>();authorities.add(newSimpleGrantedAuthority("ROLE_"+user.getRole()));returnauthorities;}publicUserregister(UserDTOuserDTO){StringencodedPassword=newBCryptPasswordEncoder().encode(userDTO.getPassword());Useruser=newUser();user.setUsername(userDTO.getUsername());user.setPassword(encodedPassword);user.setEmail(userDTO.getEmail());user.setPhone(userDTO.getPhone());user.setRole("USER");returnuserRepository.save(user);}}JWT認證java@ComponentpublicclassJwtAuthenticationFilterextendsOncePerRequestFilter{@OverrideprotectedvoiddoFilterInternal(HttpServletRequestrequest,HttpServletResponseresponse,FilterChainfilterChain)throwsServletException,IOException{Stringtoken=request.getHeader("Authorization");if(token!=null&&token.startsWith("Bearer")){token=token.substring(7);try{Claimsclaims=JwtUtil.parseToken(token);UsernamePasswordAuthenticationTokenauth=newUsernamePasswordAuthenticationToken(claims.getSubject(),null,newArrayList<>());SecurityContextHolder.getContext().setAuthentication(auth);}catch(Exceptione){SecurityContextHolder.clearContext();}}filterChain.doFilter(request,response);}}商品模塊實現(xiàn)數(shù)據(jù)庫設計sqlCREATETABLEcategories(idBIGINTAUTO_INCREMENTPRIMARYKEY,nameVARCHAR(50)NOTNULL,descriptionTEXT);CREATETABLEproducts(idBIGINTAUTO_INCREMENTPRIMARYKEY,nameVARCHAR(100)NOTNULL,descriptionTEXT,priceDECIMAL(10,2)NOTNULL,stockINTNOTNULL,category_idBIGINT,created_atTIMESTAMPDEFAULTCURRENT_TIMESTAMP,updated_atTIMESTAMPDEFAULTCURRENT_TIMESTAMPONUPDATECURRENT_TIMESTAMP,FOREIGNKEY(category_id)REFERENCEScategories(id));CREATETABLEproduct_images(idBIGINTAUTO_INCREMENTPRIMARYKEY,product_idBIGINT,urlVARCHAR(255)NOTNULL,descriptionVARCHAR(255),FOREIGNKEY(product_id)REFERENCESproducts(id));商品查詢接口java@RestController@RequestMapping("/api/products")publicclassProductController{@AutowiredprivateProductServiceproductService;@GetMappingpublicResponseEntity<?>getProducts(@RequestParam(required=false)Stringcategory,@RequestParam(required=false)Stringsearch,@RequestParam(defaultValue="1")intpage,@RequestParam(defaultValue="10")intsize){Pageablepageable=PageRequest.of(1,size);Page<ProductDTO>products=productService.getProducts(category,search,pageable);returnResponseEntity.ok(newPageResponse<>(products));}@GetMapping("/{id}")publicResponseEntity<ProductDetailDTO>getProductDetail(@PathVariable("id")Longid){ProductDetailDTOproduct=productService.getProductDetail(id);returnResponseEntity.ok(product);}}java@ServicepublicclassProductService{@AutowiredprivateProductRepositoryproductRepository;@AutowiredprivateCategoryRepositorycategoryRepository;publicPage<ProductDTO>getProducts(Stringcategory,Stringsearch,Pageablepageable){Specification<Product>spec=Specification.where(null);if(category!=null){Categorycat=categoryRepository.findByName(category).orElseThrow(()->newResourceNotFoundException("分類不存在"));spec=spec.and((root,query,criteriaBuilder)->criteriaBuilder.equal(root.get("category").get("id"),cat.getId()));}if(search!=null){spec=spec.and((root,query,criteriaBuilder)->criteriaBuilder.or(criteriaBuilder.like(root.get("name"),"%"+search+"%"),criteriaBuilder.like(root.get("description"),"%"+search+"%")));}returnproductRepository.findAll(spec,pageable).map(ProductMapper::toDTO);}publicProductDetailDTOgetProductDetail(Longid){Productproduct=productRepository.findById(id).orElseThrow(()->newResourceNotFoundException("商品不存在"));List<ProductImageDTO>images=product.getImages().stream().map(ProductImageMapper::toDTO).collect(Collectors.toList());returnProductMapper.toDetailDTO(product,images);}}購物車模塊實現(xiàn)數(shù)據(jù)庫設計sqlCREATETABLEcarts(idBIGINTAUTO_INCREMENTPRIMARYKEY,user_idBIGINTNOTNULL,product_idBIGINTNOTNULL,quantityINTDEFAULT1,created_atTIMESTAMPDEFAULTCURRENT_TIMESTAMP,FOREIGNKEY(user_id)REFERENCESusers(id),FOREIGNKEY(product_id)REFERENCESproducts(id),UNIQUEKEYunique_user_product(user_id,product_id));購物車操作接口java@RestController@RequestMapping("/api/cart")publicclassCartController{@AutowiredprivateCartServicecartService;@AutowiredprivateAuthenticationManagerauthenticationManager;@PostMappingpublicResponseEntity<CartDTO>addToCart(@RequestBodyCartItemDTOitem){Authenticationauthentication=authenticationManager.authenticate(newUsernamePasswordAuthenticationToken(item.getUsername(),null));Useruser=(User)authentication.getPrincipal();Cartcart=cartService.addToCart(user.getId(),item.getProductId(),item.getQuantity());returnResponseEntity.ok(CartMapper.toDTO(cart));}@GetMappingpublicResponseEntity<List<CartItemDTO>>getCartItems(){Authenticationauthentication=SecurityContextHolder.getContext().getAuthentication();Stringusername=authentication.getName();List<CartItem>items=cartService.getCartItems(username);returnResponseEntity.ok(items.stream().map(CartMapper::toDTO).collect(Collectors.toList()));}@PutMapping("/update")publicResponseEntity<CartDTO>updateCartItem(@RequestBodyCartUpdateDTOupdate){Authenticationauthentication=SecurityContextHolder.getContext().getAuthentication();Stringusername=authentication.getName();Cartcart=cartService.updateCartItem(username,update.getProductId(),update.getQuantity());returnResponseEntity.ok(CartMapper.toDTO(cart));}@DeleteMapping("/remove/{productId}")publicResponseEntity<Void>removeCartItem(@PathVariable("productId")LongproductId){Authenticationauthentication=SecurityContextHolder.getContext().getAuthentication();Stringusername=authentication.getName();cartService.removeCartItem(username,productId);returnResponseEntity.ok().build();}}訂單模塊實現(xiàn)數(shù)據(jù)庫設計sqlCREATETABLEorders(idBIGINTAUTO_INCREMENTPRIMARYKEY,user_idBIGINTNOTNULL,total_amountDECIMAL(10,2)NOTNULL,statusENUM('待支付','已支付','已發(fā)貨','已完成','已取消')DEFAULT'待支付',shipping_addressTEXT,payment_methodENUM('支付寶','微信支付','銀行卡')DEFAULT'支付寶',created_atTIMESTAMPDEFAULTCURRENT_TIMESTAMP,updated_atTIMESTAMPDEFAULTCURRENT_TIMESTAMPONUPDATECURRENT_TIMESTAMP,FOREIGNKEY(user_id)REFERENCESusers(id));CREATETABLEorder_items(idBIGINTAUTO_INCREMENTPRIMARYKEY,order_idBIGINT,product_idBIGINT,quantityINTNOTNULL,priceDECIMAL(10,2)NOTNULL,FOREIGNKEY(order_id)REFERENCESorders(id),FOREIGNKEY(product_id)REFERENCESproducts(id));CREATETABLEshipping(idBIGINTAUTO_INCREMENTPRIMARYKEY,order_idBIGINT,tracking_numberVARCHAR(50),shipping_dateTIMESTAMP,delivered_dateTIMESTAMP,FOREIGNKEY(order_id)REFERENCESorders(id));訂單生成服務java@ServicepublicclassOrderService{@AutowiredprivateOrderRepositoryorderRepository;@AutowiredprivateOrderItemRepositoryorderItemRepository;@AutowiredprivateCartServicecartService;@AutowiredprivateProductRepositoryproductRepository;@TransactionalpublicOrderDTOcreateOrder(Stringusername){Authenticationauthentication=SecurityContextHolder.getContext().getAuthentication();Useruser=(User)authentication.getPrincipal();List<CartItem>cartItems=cartService.getCartItems(username);if(cartItems.isEmpty()){thrownewCartEmptyException("購物車為空");}BigDecimaltotalAmount=BigDecimal.ZERO;for(CartItemitem:cartItems){Productproduct=productRepository.findById(item.getProductId()).orElseThrow(()->newResourceNotFoundException("商品不存在"));if(product.getStock()<item.getQuantity()){thrownewInsufficientStockException("商品庫存不足");}totalAmount=totalAmount.add(product.getPrice().multiply(newBigDecimal(item.getQuantity())));}//更新商品庫存for(CartItemitem:cartItems){Productproduct=productRepository.findById(item.getProductId()).orElseThrow(()->newResourceNotFoundException("商品不存在"));product.setStock(product.getStock()-item.getQuantity());productRepository.save(product);}//創(chuàng)建訂單Orderorder=newOrder();order.setUserId(user.getId());order.setTotalAmount(totalAmount);order.setStatus("待支付");order.setShippingAddress(user.getPhone());//簡化示例，實際應使用地址表order.setPaymentMethod("支付寶");OrdersavedOrder=orderRepository.save(order);//創(chuàng)建訂單項for(CartItemitem:cartItems){OrderItemorderItem=newOrderItem();orderItem.setOrderId(savedOrder.getId());orderItem.setProductId(item.getProductId());orderItem.setQuantity(item.getQuantity());orderItem.setPrice(item.getProduct().getPrice());orderItemRepository.save(orderItem);}//清空購物車cartService.clearCart(username);returnOrderMapper.toDTO(savedOrder);}}支付模塊實現(xiàn)支付集成java@RestController@RequestMapping("/api/payment")publicclassPaymentController{@AutowiredprivateOrderServiceorderService;@PostMapping("/alipay")publicResponseEntity<PaymentResponse>createAlipayOrder(@RequestBodyOrderDTOorder){//實際項目中應調(diào)用支付寶SDKStringtradeNo=UUID.randomUUID().toString();PaymentResponseresponse=newPaymentResponse();response.setTradeNo(tradeNo);response.setTotalAmount(order.getTotalAmount().toString());response.setNotifyUrl("/alipay/notify");//實際通知地址response.setReturnUrl("/alipay/return");//實際回調(diào)地址//保存訂單支付狀態(tài)orderService.updateOrderPaymentStatus(order.getId(),"待支付",tradeNo);returnResponseEntity.ok(response);}@GetMapping("/notify")publicStringalipayNotify(@RequestParamStringparams){//處理支付寶異步通知//實際項目中需要驗證簽名//更新訂單支付狀態(tài)//...return"success";}@GetMapping("/return")publicStringalipayReturn(@RequestParamStringpaymentStatus){//處理支付寶同步跳轉(zhuǎn)//...return"success";}}后臺管理模塊實現(xiàn)后臺用戶管理java@RestController@RequestMapping("/api/admin/users")publicclassAdminUserController{@AutowiredprivateAdminUserServiceadminUserService;@GetMappingpublicResponseEntity<?>getUsers(@RequestParam(required=false)Stringusername,@RequestParam(required=false)Stringrole,@RequestParam(defaultValue="1")intpage,@RequestParam(defaultValue="10")intsize){Pageablepageable=PageRequest.of(1,size);Page<UserDTO>users=adminUserService.getUsers(username,role,pageable);returnResponseEntity.ok(newPa