生产构build引发意想不到的错误

前几天我build立我的Angular 4和Spring Boot应用与npm run build和一切正常，但现在我得到了这样一个错误：

 ERROR in Can't resolve all parameters for DataService in C:/Users/Michał/IdeaProjects/Inventory/src/main/frontend/src/app/services/data.service.ts: (?, [object Object]). ERROR in ./src/main.ts Module not found: Error: Can't resolve './$$_gendir/app/app.module.ngfactory' in 'C:\Users\Michał\IdeaProjects\Inventory\src\main\frontend\src' @ ./src/main.ts 3:0-74 @ multi ./src/main.ts 

我的data.service类看起来：

 @Injectable() export class DataService { constructor(private url: string, private http: HttpClient) { } getAllWithPaging(params: HttpParams){ return this.http.get(this.url + '/withPaging?' + params.toString()); } insertOrUpdate(resources){ return this.http.post(this.url, resources); } delete(resources){ return this.http.delete(this.url + '/' + resources.id, {responseType: 'text'}); } get getUrl() : string{ return this.url; } get getHttp(): HttpClient{ return this.http } 

自一周以来有什么变化？