Не удается сохранить/открыть файл на Spring

Question

Я создал страницу, которая позволяет пользователю загружать файл, но функция, которая должна сохранять файл, не может открыть файл в файловой системе, вот код:

@RequestMapping(value="/upload", method=RequestMethod.POST) 
public @ResponseBody String handleFileUpload(@RequestParam("file") MultipartFile file){ 
    String name="dsotm.png"; 
    FileSystemResource res; 
    res=new FileSystemResource(name); 
    if (!file.isEmpty()) { 
     System.out.println("file is not empty"); 
     try { 
      byte[] bytes = file.getBytes(); 
      System.out.println(bytes[1]); 
      BufferedOutputStream stream = 
        new BufferedOutputStream(new FileOutputStream(res.getFile())); 
      stream.write(bytes); 
      stream.close(); 
      return "You successfully uploaded " + name + "!"; 
     } catch (Exception e) { 
      e.printStackTrace(); 
      return "You failed to upload " + name + " => " + e.getMessage(); 

     } 
    } else { 
     return "You failed to upload " + name + " because the file was empty."; 
    } 
} 

Вот это StackTrace:

java.io.FileNotFoundException: dsotm.png (Accesso negato) 
at java.io.FileOutputStream.open(Native Method) 
at java.io.FileOutputStream.<init>(Unknown Source) 
at java.io.FileOutputStream.<init>(Unknown Source) 
at it.unibo.ai.fratup.controller.HomeController.handleFileUpload(HomeController.java:108) 
at it.unibo.ai.fratup.controller.HomeController$$FastClassByCGLIB$$98be424b.invoke(<generated>) 
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) 
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:698) 
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150) 
at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:51) 
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) 
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:91) 
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) 
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:631) 
at it.unibo.ai.fratup.controller.HomeController$$EnhancerByCGLIB$$3690e43c.handleFileUpload(<generated>) 
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) 
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
at java.lang.reflect.Method.invoke(Unknown Source) 
at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:219) 
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132) 
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104) 
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:745) 
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:686) 
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80) 
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925) 
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856) 
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:936) 
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:838) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:648) 
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) 
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291) 
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) 
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) 
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330) 
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:118) 
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:84) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) 
at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) 
at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:103) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) 
at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:113) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) 
at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:154) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) 
at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:45) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) 
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:199) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) 
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:110) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) 
at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:57) 
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) 
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) 
at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:50) 
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) 
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342) 
at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:192) 
at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:160) 
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:343) 
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:260) 
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) 
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219) 
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106) 
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) 
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142) 
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) 
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610) 
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88) 
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518) 
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091) 
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:668) 
at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:223) 
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1517) 
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1474) 
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) 
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) 
at java.lang.Thread.run(Unknown Source) 

Я действительно не знаю, что делать .... код кажется нормально, но независимо от того, что я делаю, я не могу получить доступ к файлу система.

Answer 1

Вы можете пропустить этот следующий код:

FileSystemResource res; 
    res=new FileSystemResource(name); 

И заменить res.getFile() в следующем коде с:

BufferedOutputStream stream = 
       new BufferedOutputStream(new FileOutputStream(new File(name))); 

где name является переменной, вы объявляли ранее.

Если проблема существует, проверить этот учебник с весны here.