So implementieren Sie das Bestell-Applet in SpringBoot

/**
 * 登录相关
 */
@RequestMapping("users")
@RestController
public class UserController{
	@Autowired
	private UserService userService;
	@Autowired
	private TokenService tokenService;
	/**
	 * 登录
	 */
	@IgnoreAuth
	@PostMapping(value = "/login")
	public R login(String username, String password, String captcha, HttpServletRequest request) {
		UserEntity user = userService.selectOne(new EntityWrapper<UserEntity>().eq("username", username));
		if(user==null || !user.getPassword().equals(password)) {
			return R.error("账号或密码不正确");
		}
		String token = tokenService.generateToken(user.getId(),username, "users", user.getRole());
		return R.ok().put("token", token);
	}
	/**
	 * 注册
	 */
	@IgnoreAuth
	@PostMapping(value = "/register")
	public R register(@RequestBody UserEntity user){
//    	ValidatorUtils.validateEntity(user);
    	if(userService.selectOne(new EntityWrapper<UserEntity>().eq("username", user.getUsername())) !=null) {
    		return R.error("用户已存在");
    	}
        userService.insert(user);
        return R.ok();
    }
	/**
	 * 退出
	 */
	@GetMapping(value = "logout")
	public R logout(HttpServletRequest request) {
		request.getSession().invalidate();
		return R.ok("退出成功");
	}
	/**
     * 密码重置
     */
    @IgnoreAuth
	@RequestMapping(value = "/resetPass")
    public R resetPass(String username, HttpServletRequest request){
    	UserEntity user = userService.selectOne(new EntityWrapper<UserEntity>().eq("username", username));
    	if(user==null) {
    		return R.error("账号不存在");
    	}
    	user.setPassword("123456");
        userService.update(user,null);
        return R.ok("密码已重置为：123456");
    }
	/**
     * 列表
     */
    @RequestMapping("/page")
    public R page(@RequestParam Map<String, Object> params,UserEntity user){
        EntityWrapper<UserEntity> ew = new EntityWrapper<UserEntity>();
    	PageUtils page = userService.queryPage(params, MPUtil.sort(MPUtil.between(MPUtil.allLike(ew, user), params), params));
        return R.ok().put("data", page);
    }
	/**
     * 列表
     */
    @RequestMapping("/list")
    public R list( UserEntity user){
       	EntityWrapper<UserEntity> ew = new EntityWrapper<UserEntity>();
      	ew.allEq(MPUtil.allEQMapPre( user, "user"));
        return R.ok().put("data", userService.selectListView(ew));
    }
    /**
     * 信息
     */
    @RequestMapping("/info/{id}")
    public R info(@PathVariable("id") String id){
        UserEntity user = userService.selectById(id);
        return R.ok().put("data", user);
    }
    /**
     * 获取用户的session用户信息
     */
    @RequestMapping("/session")
    public R getCurrUser(HttpServletRequest request){
    	Long id = (Long)request.getSession().getAttribute("userId");
        UserEntity user = userService.selectById(id);
        return R.ok().put("data", user);
    }
    /**
     * 保存
     */
    @PostMapping("/save")
    public R save(@RequestBody UserEntity user){
//    	ValidatorUtils.validateEntity(user);
    	if(userService.selectOne(new EntityWrapper<UserEntity>().eq("username", user.getUsername())) !=null) {
    		return R.error("用户已存在");
    	}
        userService.insert(user);
        return R.ok();
    }
    /**
     * 修改
     */
    @RequestMapping("/update")
    public R update(@RequestBody UserEntity user){
//        ValidatorUtils.validateEntity(user);
    	UserEntity u = userService.selectOne(new EntityWrapper<UserEntity>().eq("username", user.getUsername()));
    	if(u!=null && u.getId()!=user.getId() && u.getUsername().equals(user.getUsername())) {
    		return R.error("用户名已存在。");
    	}
        userService.updateById(user);//全部更新
        return R.ok();
    }
    /**
     * 删除
     */
    @RequestMapping("/delete")
    public R delete(@RequestBody Long[] ids){
        userService.deleteBatchIds(Arrays.asList(ids));
        return R.ok();
    }
}

/**
 * 订单
 * 后端接口
 * @author 小孟v：jishulearn
 * @email
 * @date 2022-06-26 09:41:24
 */
@RestController
@RequestMapping("/orders")
public class OrdersController {
    @Autowired
    private OrdersService ordersService;
    @Autowired
    private CaipinxinxiService caipinxinxiService;
    /**
     * 后端列表
     */
    @RequestMapping("/page")
    public R page(@RequestParam Map<String, Object> params,OrdersEntity orders,
		HttpServletRequest request){
    	if(!request.getSession().getAttribute("role").toString().equals("管理员")) {
    		orders.setUserid((Long)request.getSession().getAttribute("userId"));
    	}
        EntityWrapper<OrdersEntity> ew = new EntityWrapper<OrdersEntity>();
		PageUtils page = ordersService.queryPage(params, MPUtil.sort(MPUtil.between(MPUtil.likeOrEq(ew, orders), params), params));
        return R.ok().put("data", page);
    }
    /**
     * 前端列表
     */
    @RequestMapping("/list")
    public R list(@RequestParam Map<String, Object> params,OrdersEntity orders, HttpServletRequest request){
        EntityWrapper<OrdersEntity> ew = new EntityWrapper<OrdersEntity>();
		PageUtils page = ordersService.queryPage(params, MPUtil.sort(MPUtil.between(MPUtil.likeOrEq(ew, orders), params), params));
        return R.ok().put("data", page);
    }
	/**
     * 列表
     */
    @RequestMapping("/lists")
    public R list( OrdersEntity orders){
       	EntityWrapper<OrdersEntity> ew = new EntityWrapper<OrdersEntity>();
      	ew.allEq(MPUtil.allEQMapPre( orders, "orders"));
        return R.ok().put("data", ordersService.selectListView(ew));
    }
	 /**
     * 查询
     */
    @RequestMapping("/query")
    public R query(OrdersEntity orders){
        EntityWrapper< OrdersEntity> ew = new EntityWrapper< OrdersEntity>();
 		ew.allEq(MPUtil.allEQMapPre( orders, "orders"));
		OrdersView ordersView =  ordersService.selectView(ew);
		return R.ok("查询订单成功").put("data", ordersView);
    }
    /**
     * 后端详情
     */
    @RequestMapping("/info/{id}")
    public R info(@PathVariable("id") Long id){
        OrdersEntity orders = ordersService.selectById(id);
        return R.ok().put("data", orders);
    }
    /**
     * 前端详情
     */
    @RequestMapping("/detail/{id}")
    public R detail(@PathVariable("id") Long id){
        OrdersEntity orders = ordersService.selectById(id);
        return R.ok().put("data", orders);
    }
    /**
     * 后端保存
     */
    @RequestMapping("/save")
    public R save(@RequestBody OrdersEntity orders, HttpServletRequest request){
    	orders.setId(new Date().getTime()+new Double(Math.floor(Math.random()*1000)).longValue());
    	//ValidatorUtils.validateEntity(orders);
    	orders.setUserid((Long)request.getSession().getAttribute("userId"));
        ordersService.insert(orders);
        return R.ok();
    }
    /**
     * 前端保存
     */
    @RequestMapping("/add")
    public R add(@RequestBody OrdersEntity orders, HttpServletRequest request){
    	orders.setId(new Date().getTime()+new Double(Math.floor(Math.random()*1000)).longValue());
    	//ValidatorUtils.validateEntity(orders);
        CaipinxinxiEntity caipinxinxiEntity = caipinxinxiService.selectById(orders.getGoodid());
        if(caipinxinxiEntity.getStore()<orders.getBuynumber()){
            return R.error("库存不足");
        }
        caipinxinxiEntity.setStore(caipinxinxiEntity.getStore()-orders.getBuynumber());
        caipinxinxiEntity.setSell(caipinxinxiEntity.getSell()+orders.getBuynumber());
        caipinxinxiService.updateById(caipinxinxiEntity);
        ordersService.insert(orders);
        return R.ok();
    }
    /**
     * 修改
     */
    @RequestMapping("/update")
    public R update(@RequestBody OrdersEntity orders, HttpServletRequest request){
        //ValidatorUtils.validateEntity(orders);
        ordersService.updateById(orders);//全部更新
        return R.ok();
    }