Question

我正在尝试使用MultipartFile实现一个使用Spring上传文件的休息Web服务。我不使用Spring Boot，我的类路径中有commons-fileupload库。

我阅读的Spring文档说：

您需要在web.xml中使用“multipart-config”部分标记DispatcherServlet，或者在编程Servlet注册中使用javax.servlet.MultipartConfigElement标记，或者在自定义Servlet类可能使用javax.servlet的情况下。 Servlet类上的annotation.MultipartConfig注释...一旦以上述方式之一启用了Servlet 3.0多部分解析，就可以将StandardServletMultipartResolver添加到Spring配置中

因此我将这个bean添加到我的AppConfig类：

 @Bean
 public StandardServletMultipartResolver multipartResolver() {
    return new StandardServletMultipartResolver();
 }

并使用MultipartConfig注释班级：

@EnableWebMvc
@MultipartConfig(maxFileSize = 5120)
public class AppConfig extends WebMvcConfigurerAdapter{
 ...
}

但是当我打电话给服务时我得到了这个例外：

Caused by: org.springframework.web.multipart.MultipartException: Could not parse multipart servlet request; nested exception is java.lang.UnsupportedOperationException: SRVE8020E: Servlet does not accept multipart request
    at org.springframework.web.multipart.support.StandardMultipartHttpServletRequest.parseRequest(StandardMultipartHttpServletRequest.java:111)
    at org.springframework.web.multipart.support.StandardMultipartHttpServletRequest.<init>(StandardMultipartHttpServletRequest.java:85)
    at org.springframework.web.multipart.support.StandardServletMultipartResolver.resolveMultipart(StandardServletMultipartResolver.java:76)
    at org.springframework.web.multipart.support.MultipartFilter.doFilterInternal(MultipartFilter.java:112)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:207)
    at [internal classes]
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:207)
    ... 1 more
Caused by: java.lang.UnsupportedOperationException: SRVE8020E: Servlet does not accept multipart request
    at com.ibm.ws.webcontainer.srt.SRTServletRequest.prepareMultipart(SRTServletRequest.java:3657)
    at [internal classes]
    at org.springframework.web.multipart.support.StandardMultipartHttpServletRequest.parseRequest(StandardMultipartHttpServletRequest.java:92)

如果我使用CommonsMultipartResolver代替StandardServletMultipartResolver，我会收到相同的错误。

这是我初始化我的应用程序的方式：

public class AppInitializer implements WebApplicationInitializer {

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        AnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();
        context.register(AppConfig.class);
        context.setServletContext(servletContext);

        servletContext.addListener(new ContextLoaderListener(context));

        ServletRegistration.Dynamic dispatcher = servletContext.addServlet("dispatcherServlet", new DispatcherServlet(context));
        dispatcher.setLoadOnStartup(1);
        dispatcher.addMapping("/");


        CharacterEncodingFilter characterEncodingFilter = new CharacterEncodingFilter();
        characterEncodingFilter.setEncoding("UTF-8");
        characterEncodingFilter.setForceEncoding(true);

        EnumSet<DispatcherType> dispatcherTypes = EnumSet.of(DispatcherType.REQUEST, DispatcherType.FORWARD);
        FilterRegistration.Dynamic characterEncoding = servletContext.addFilter("CharacterEncodingFilter", characterEncodingFilter);
        characterEncoding.addMappingForUrlPatterns(dispatcherTypes, true, "/*");

    }
}

我还尝试添加MultipartFilter，但没有运气。

MultipartFilter multipartFilter = new MultipartFilter();
FilterRegistration.Dynamic multipart = servletContext.addFilter("multipartFilter", multipartFilter);
    multipart.addMappingForUrlPatterns(EnumSet.of(DispatcherType.REQUEST), true, "/*");

这有必要吗？我究竟做错了什么？我想我在整个网络上都在寻找解决方案，但他们都使用MultipartConfigElement和MultipartConfigFactory的春季启动。也许问题是我使用服务的方式？

这是我的控制器方法：

@RequestMapping(value = "/upload", method = RequestMethod.POST, consumes = "multipart/form-data" )
public Long uploadAttachment(@RequestParam("cn") String callerName, @RequestParam("cs") String callerService, @RequestParam("file")  MultipartFile file)

这就是我消费它的方式：

File file = new File("C:\\Users\\cte0289\\Documents\\Email\\document.docx");
RestTemplate rest = new RestTemplate();
LinkedMultiValueMap<String, Object> map = new LinkedMultiValueMap<String, Object>();

map.add("cn", callerName);
map.add("cs", callerService);
map.add("file", file);            
Long response = rest.postForObject(url + "/upload", map, Long.class);

请帮助我不知道还能做什么。

Answer 1

我想你可能想尝试这样的事情：

        public class AppInitializer implements WebApplicationInitializer {

        @Override
        public void onStartup(ServletContext servletContext) throws ServletException {
            AnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();
            context.register(AppConfig.class);
            context.setServletContext(servletContext);

            servletContext.addListener(new ContextLoaderListener(context));

            ServletRegistration.Dynamic dispatcher = servletContext.addServlet("dispatcherServlet", new DispatcherServlet(context));
            dispatcher.setLoadOnStartup(1);
            dispatcher.addMapping("/");
dispatcher.setMultipartConfig(getMultipartConfigElement());


            CharacterEncodingFilter characterEncodingFilter = new CharacterEncodingFilter();
            characterEncodingFilter.setEncoding("UTF-8");
            characterEncodingFilter.setForceEncoding(true);

            EnumSet<DispatcherType> dispatcherTypes = EnumSet.of(DispatcherType.REQUEST, DispatcherType.FORWARD);
            FilterRegistration.Dynamic characterEncoding = servletContext.addFilter("CharacterEncodingFilter", characterEncodingFilter);
            characterEncoding.addMappingForUrlPatterns(dispatcherTypes, true, "/*");

        }

    private MultipartConfigElement getMultipartConfigElement(){
            MultipartConfigElement multipartConfigElement = new MultipartConfigElement("C:/tmp", 1024*1024*5, 1024*1024*5*5, 1024*1024);
            return multipartConfigElement;
        }
    }

Answer 2

配置Spring项目以使用java配置处理文件上载的正确方法是：如果要使用Commons FileUpload库进行配置，只需将此bean包含在Configuration类中，并在类路径中添加jar

@Bean
public CommonsMultipartResolver multipartResolver(){
    CommonsMultipartResolver resolver = new CommonsMultipartResolver();
    resolver.setMaxUploadSize(5242880); // set the size limit
    return resolver;
}

如果你想用Servlet 3.0配置项目，因为@AlieneilA说你必须在调度程序servlet中设置MultipartConfig元素：

dispatcher.setMultipartConfig(new MultipartConfigElement("C:/tmp", 1024*1024*5, 1024*1024*5*5, 1024*1024));

并在配置类中包含此bean（在我的例子中为AppConfig）：

@Bean
public StandardServletMultipartResolver multipartResolver() {
   return new StandardServletMultipartResolver();
}

我将文件插入LinkedMultiValueMap的方式错了。我不得不使用FileSystemResource：

File file = new File("C:\\document.doc");
RestTemplate rest = new RestTemplate();
LinkedMultiValueMap<String, Object> map = new LinkedMultiValueMap<String, Object>();

map.add("param1", param1);
map.add("param2", param2);
map.add("file", new FileSystemResource(file));            
Long response = rest.postForObject(url, map, Long.class);

或MockMultipartFile，如此答案所示：https://stackoverflow.com/a/38270420/6503002

在这种情况下，包括spring mock作为依赖：

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-mock</artifactId>
    <version>2.0.8</version>
</dependency>

Answer 3

如果有人为Web应用程序初始化配置扩展AbstractAnnotationConfigDispatcherServletInitializer类，下面的简单配置将启用MultiPart功能 -

import javax.servlet.MultipartConfigElement;
import javax.servlet.ServletRegistration.Dynamic;

import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;

public class WebApplicationInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {

    @Override
    protected Class<?>[] getRootConfigClasses() {
        return null;
    }

    @Override
    protected Class<?>[] getServletConfigClasses() {
        return new Class[] { AppConfig.class };
    }

    @Override
    protected String[] getServletMappings() {
        return new String[] { "/" };
    }

    @Override
    protected void customizeRegistration(Dynamic registration) {

        MultipartConfigElement multiPart = new MultipartConfigElement("C:/temp/",
                1024 * 1024 * 5, 1024 * 1024 * 10, 1024 * 1024 * 3);

        registration.setMultipartConfig(multiPart);
    }

}

Spring休息MultiPart文件上传与Java配置没有Spring启动

3 个答案: