由于未提供多部件配置，因此无法处理部件

Question

我写了一个简单的控制器来上传文件：

@RestEndpoint
public class ImageController {
    @Autowired
    GridFsTemplate mTemplate;

    @RequestMapping(value = "images", method = RequestMethod.POST)
    public @ResponseBody String testPhoto(@RequestParam String name, @RequestParam String directory, @RequestParam MultipartFile file) throws IOException {

        if(!file.isEmpty()){
            final byte[] bytes = file.getBytes();
            InputStream inputStream = new ByteArrayInputStream(bytes);
            mTemplate.store(inputStream, "name");

            return "uploaded photo";
        }

        return "failed";
    }

} 

@RestEndpoint注释是：

@Target({ ElementType.TYPE })
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Controller
public @interface RestEndpoint
{
    String value() default "";
}

我的ContextCOnfiguration类是：

@Configuration
@EnableWebMvc
@ComponentScan(
    basePackages = "com.questter.site",
    useDefaultFilters = false,
    includeFilters =
    @ComponentScan.Filter({RestEndpoint.class, RestEndpointAdvice.class})
)
public class RestServletContextConfiguration extends WebMvcConfigurerAdapter {
    @Bean
    public CommonsMultipartResolver multiPartResolver(){

        CommonsMultipartResolver resolver = new CommonsMultipartResolver();
        return resolver;
    }
...
}

- - 更新 - -

web.xml文件：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
                         http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
     version="3.1">

    <display-name>Spring Application</display-name>

    <jsp-config>
        <jsp-property-group>
            <url-pattern>*.jsp</url-pattern>
            <url-pattern>*.jspf</url-pattern>
            <page-encoding>UTF-8</page-encoding>
            <scripting-invalid>true</scripting-invalid>
            <include-prelude>/WEB-INF/jsp/base.jspf</include-prelude>
            <trim-directive-whitespaces>true</trim-directive-whitespaces>
            <default-content-type>text/html</default-content-type>
        </jsp-property-group>
    </jsp-config>

    <!--<context-param>-->
        <!--<param-name>spring.profiles.active</param-name>-->
        <!--<param-value>development</param-value>-->
    <!--</context-param>-->

    <session-config>
        <session-timeout>30</session-timeout>
        <cookie-config>
            <http-only>true</http-only>
        </cookie-config>
        <tracking-mode>COOKIE</tracking-mode>
    </session-config>

    <distributable />

</web-app>

- - 更新 - -

public class Bootstrap implements WebApplicationInitializer
{

    @Override
    public void onStartup(ServletContext container) throws ServletException
    {
        container.getServletRegistration("default").addMapping("/resource/*");

        AnnotationConfigWebApplicationContext rootContext =
            new AnnotationConfigWebApplicationContext();
        rootContext.register(RootContextConfiguration.class);
        container.addListener(new ContextLoaderListener(rootContext));

        AnnotationConfigWebApplicationContext webContext =
            new AnnotationConfigWebApplicationContext();
        webContext.register(WebServletContextConfiguration.class);
        ServletRegistration.Dynamic dispatcher = container.addServlet(
            "springWebDispatcher", new DispatcherServlet(webContext)
        );
        dispatcher.setLoadOnStartup(1);
        dispatcher.setMultipartConfig(new MultipartConfigElement(
            null, 20_971_520L, 41_943_040L, 512_000
        ));
        dispatcher.addMapping("/");

        AnnotationConfigWebApplicationContext restContext =
                new AnnotationConfigWebApplicationContext();
        restContext.register(RestServletContextConfiguration.class);
        DispatcherServlet servlet = new DispatcherServlet(restContext);
        servlet.setDispatchOptionsRequest(true);
        dispatcher = container.addServlet(
                "springRestDispatcher", servlet
        );
        dispatcher.setLoadOnStartup(2);
        dispatcher.addMapping("/rest/*");

        rootContext.refresh();
        DbBootstrap dbBootstrap = rootContext.getBean(DbBootstrap.class);
        dbBootstrap.init();

    }


}

当执行一个帖子请求（使用邮递员）时，我得到：

HTTP Status 500 - Request processing failed; nested exception is java.lang.IllegalArgumentException:Expected MultipartHttpServletRequest: is a MultipartResolver configured 

我已经在stackoverflow上查看了一些类似的问题，但没有一个答案对我有帮助。

Spring版本是：4.0.4

任何帮助将不胜感激（当然竖起大拇指）。

谢谢

Answer 1

我不知道他们为什么这样做，但上下文中的MultipartResolver bean需要命名为multipartResolver 。 将@Bean方法重命名为

public CommonsMultipartResolver multipartResolver(){ // lowercase 'P'

或者明确地给它命名

@Bean(name = "multipartResolver")
public CommonsMultipartResolver canBeCalledAnything(){

Answer 2

allowCasualMultipartParsing="true"

在context.xml中的context标签上，它对我有用

Answer 3

除了没有找到多部件配置之外，它是直截了当的。 虽然您提供了multipartResolver bean。

问题是，在Spring Security过滤器之前指定MultipartFilter时 ，它会尝试获取multipartResolver bean但无法找到它。 因为它期望bean名称/ id为filterMultipartResolver而不是multipartResolver 。

帮自己一个忙。 请更改bean配置如下 -

@Bean
public CommonsMultipartResolver filterMultipartResolver(){
    CommonsMultipartResolver resolver = new 
    CommonsMultipartResolver();
    return resolver;
}

要么

@Bean(name = "filterMultipartResolver")
public CommonsMultipartResolver multiPartResolver(){
    CommonsMultipartResolver resolver = new 
    CommonsMultipartResolver();
    return resolver;
}

Answer 4

R. Ali Ashik的答案为我工作。

以下是我正在研究的项目的pom.xml的相关部分：

  <properties> <springframework.version>5.0.2.RELEASE</springframework.version> <springsecurity.version>5.0.0.RELEASE</springsecurity.version> <hibernate.version>5.2.17.Final</hibernate.version> <mysql.connector.version>8.0.11</mysql.connector.version> 

因为，我有一个带有持久身份验证设置的自定义登录页面，我还需要具备以下条件：

public class SecurityWebApplicationInitializer extends AbstractSecurityWebApplicationInitializer {

        @Override
        protected void beforeSpringSecurityFilterChain(ServletContext servletContext) {
            insertFilters(servletContext, new MultipartFilter());
        }
    }

但正如R. Ali Ashik所指出的那样，实际的关键是：

@Bean(name = "filterMultipartResolver")
public CommonsMultipartResolver multiPartResolver(){
    CommonsMultipartResolver resolver = new 
    CommonsMultipartResolver();
    return resolver;
}

上下文中的相关参考资料是： Class MultipartFilter

相关文字如下：

Looks up the MultipartResolver in Spring's root web application context. Supports a "multipartResolverBeanName" filter init-param in web.xml; the default bean name is "filterMultipartResolver". Looks up the MultipartResolver on each request, to avoid initialization order issues (when using ContextLoaderServlet, the root application context will get initialized after this filter).