Question

我正在使用MultipartHttpServletRequest从客户端将图像上传到浏览器

因此，我下载了以下依赖项

<dependency>
    <groupId>commons-fileupload</groupId>
        <artifactId>commons-fileupload</artifactId>
        <version>1.3.3</version>
    </dependency>
    <dependency>
    <groupId>commons-io</groupId>
    <artifactId>commons-io</artifactId>
    <version>2.4</version>
</dependency>

并使用基于Java的配置添加到bean中

@Bean(name = "multipartResolver")
    public CommonsMultipartResolver createMultipartResolver() {
        CommonsMultipartResolver resolver=new CommonsMultipartResolver();
        resolver.setDefaultEncoding("utf-8");
        return resolver;
    }

这是我上传文件的请求映射方法

@RequestMapping(value = "/rest/ModifyUser", method = RequestMethod.POST)
    public ServiceResponse modifyUser(MultipartHttpServletRequest request,HttpServlet response)
    {
        Iterator<String> itr = request.getFileNames();

        String id=request.getParameter("id");
        String firstName=request.getParameter("fname");
        String lastName=request.getParameter("lname");
        String password=request.getParameter("pass");
        String email=request.getParameter("email");

        MultipartFile multipartFileImage = request.getFile(itr.next());

        try {
            File saveImage = new File("C://"+"("+id+")"+multipartFileImage.getOriginalFilename());

        }catch(Exception e) {
            e.printStackTrace();
        }
        return response(abc(user));
    }

但是当我遇到以上@RequestMapping时，我会得到

严重[http-nio-8080-exec-8] org.apache.catalina.core.StandardWrapperValve.invoke Servlet.service（）路径为[/ Fiserv]的上下文中用于servlet [dispatcher]的方法异常[请求处理失败；嵌套异常为 org.springframework.beans.BeanInstantiationException：失败实例化[javax.servlet.http.HttpServlet]：是抽象的吗类？;嵌套的异常是java.lang.InstantiationException]，其中根本原因java.lang.InstantiationException在 sun.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance（InstantiationExceptionConstructorAccessorImpl.java:48）在java.lang.reflect.Constructor.newInstance（Constructor.java:423）在 org.springframework.beans.BeanUtils.instantiateClass（BeanUtils.java:142）在 org.springframework.beans.BeanUtils.instantiateClass（BeanUtils.java:102）在 org.springframework.web.method.annotation.ModelAttributeMethodProcessor.createAttribute（ModelAttributeMethodProcessor.java:141）在 org.springframework.web.servlet.mvc.method.annotation.ServletModelAttributeMethodProcessor.createAttribute（ServletModelAttributeMethodProcessor.java:81）在 org.springframework.web.method.annotation.ModelAttributeMethodProcessor.resolveArgument（ModelAttributeMethodProcessor.java:101）在 org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument（HandlerMethodArgumentResolverComposite.java:121）在 org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues（InvocableHandlerMethod.java:158）在 org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest（InvocableHandlerMethod.java:128）在 org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle（ServletInvocableHandlerMethod.java:97）在 org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod（RequestMappingHandlerAdapter.java:827）在 org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal（RequestMappingHandlerAdapter.java:738）在 org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle（AbstractHandlerMethodAdapter.java:85）在 org.springframework.web.servlet.DispatcherServlet.doDispatch（DispatcherServlet.java:967）在 org.springframework.web.servlet.DispatcherServlet.doService（DispatcherServlet.java:901）在 org.springframework.web.servlet.FrameworkServlet.processRequest（FrameworkServlet.java:970）在 org.springframework.web.servlet.FrameworkServlet.doPost（FrameworkServlet.java:872）在javax.servlet.http.HttpServlet.service（HttpServlet.java:661）处 org.springframework.web.servlet.FrameworkServlet.service（FrameworkServlet.java:846）在javax.servlet.http.HttpServlet.service（HttpServlet.java:742） org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:231）在 org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166）在 org.apache.tomcat.websocket.server.WsFilter.doFilter（WsFilter.java:52）在 org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:193）在 org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166）在 org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:330）在 org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke（FilterSecurityInterceptor.java:118）在 org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter（FilterSecurityInterceptor.java:84）在 org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在 org.springframework.security.web.access.ExceptionTranslationFilter.doFilter（ExceptionTranslationFilter.java:113）在 org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在 org.springframework.security.web.session.SessionManagementFilter.doFilter（SessionManagementFilter.java:103）在 org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在 org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter（AnonymousAuthenticationFilter.java:113）在 org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在 org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter（SecurityContextHolderAwareRequestFilter.java:154）在 org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在 org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter（RequestCacheAwareFilter.java:45）在 org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在 org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter（AbstractAuthenticationProcessingFilter.java:199）在 org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在 org.springframework.security.web.authentication.logout.LogoutFilter.doFilter（LogoutFilter.java:110）在 org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在 org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter（SecurityContextPersistenceFilter.java:87）在 org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在 org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal（WebAsyncManagerIntegrationFilter.java:50）在 org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:107）在 org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在 org.springframework.security.web.FilterChainProxy.doFilterInternal（FilterChainProxy.java:192）在 org.springframework.security.web.FilterChainProxy.doFilter（FilterChainProxy.java:160）在 org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate（DelegatingFilterProxy.java:346）在 org.springframework.web.filter.DelegatingFilterProxy.doFilter（DelegatingFilterProxy.java:262）在 org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:193）在 org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:166）在 org.apache.catalina.core.StandardWrapperValve.invoke（StandardWrapperValve.java:199）在 org.apache.catalina.core.StandardContextValve.invoke（StandardContextValve.java:96）在 org.apache.catalina.authenticator.AuthenticatorBase.invoke（AuthenticatorBase.java:504）在 org.apache.catalina.core.StandardHostValve.invoke（StandardHostValve.java:140）在 org.apache.catalina.valves.ErrorReportValve.invoke（ErrorReportValve.java:81）在 org.apache.catalina.valves.AbstractAccessLogValve.invoke（AbstractAccessLogValve.java:650）在 org.apache.catalina.core.StandardEngineValve.invoke（StandardEngineValve.java:87）在 org.apache.catalina.connector.CoyoteAdapter.service（CoyoteAdapter.java:342）在 org.apache.coyote.http11.Http11Processor.service（Http11Processor.java:803）在 org.apache.coyote.AbstractProcessorLight.process（AbstractProcessorLight.java:66）在 org.apache.coyote.AbstractProtocol $ ConnectionHandler.process（AbstractProtocol.java:790）在 org.apache.tomcat.util.net.NioEndpoint $ SocketProcessor.doRun（NioEndpoint.java:1459）在 org.apache.tomcat.util.net.SocketProcessorBase.run（SocketProcessorBase.java:49）在 java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1149）在 java.util.concurrent.ThreadPoolExecutor $ Worker.run（ThreadPoolExecutor.java:624）在 org.apache.tomcat.util.threads.TaskThread $ WrappingRunnable.run（TaskThread.java:61）在java.lang.Thread.run（Thread.java:748）

Answer 1

您不应使用HttpServlet作为方法参数，因为该参数现在将被解释为常规对象，Spring会尝试实例化它。 Spring创建了一个实例，因为它不是supported arguments之一。现在，它被解释为任何其他对象（表中的最后一项）。它不是简单的对象（String，int等），因此它将尝试构造实例。创建实例将失败，因为HttpServlet并不是那样使用的。

您可能想改用HttpServletResponse。但是，由于根本没有在该方法中使用该参数，因此最好将其删除。

MultipartHttpServletRequest BeanInstantiationException根本原因java.lang.InstantiationException

1 个答案: