SpringBoot中的multipartResolver上传文件配置

这篇文章主要介绍了SpringBoot中的multipartResolver上传文件配置，具有很好的参考价值，希望对大家有所帮助。如有错误或未考虑完全的地方，望不吝赐教

multipartResolver上传文件配置

1、gradle配置

				?

									compile ('commons-io:commons-io:1.4')

									compile('commons-fileupload:commons-fileupload:1.2.1')

2、注册Bean

				?

									@Bean(name = "multipartResolver")

									public MultipartResolver multipartResolver(){

									    CommonsMultipartResolver resolver = new CommonsMultipartResolver();

									    resolver.setDefaultEncoding("UTF-8");

									    //resolveLazily属性启用是为了推迟文件解析，以在在UploadAction中捕获文件大小异常

									    resolver.setResolveLazily(true);

									    resolver.setMaxInMemorySize(40960);

									    //上传文件大小 50M 50*1024*1024

									    resolver.setMaxUploadSize(50*1024*1024);

									    return resolver;

									}

SpringBoot MultipartResolver的坑

在使用springBoot上传文件的时候，我们会用到MultipartResolver。我看通过源码可以看到

				?

									@Configuration

									@ConditionalOnClass({ Servlet.class, StandardServletMultipartResolver.class,

									  MultipartConfigElement.class })

									@ConditionalOnProperty(prefix = "spring.http.multipart", name = "enabled", matchIfMissing = true)

									@EnableConfigurationProperties(MultipartProperties.class)

									public class MultipartAutoConfiguration {

									 private final MultipartProperties multipartProperties;

									 public MultipartAutoConfiguration(MultipartProperties multipartProperties) {

									  this.multipartProperties = multipartProperties;

									 }

									 @Bean

									 @ConditionalOnMissingBean({ MultipartConfigElement.class,

									   CommonsMultipartResolver.class })

									 public MultipartConfigElement multipartConfigElement() {

									  return this.multipartProperties.createMultipartConfig();

									 }

									 @Bean(name = DispatcherServlet.MULTIPART_RESOLVER_BEAN_NAME)

									 @ConditionalOnMissingBean(MultipartResolver.class)

									 public StandardServletMultipartResolver multipartResolver() {

									  StandardServletMultipartResolver multipartResolver = new StandardServletMultipartResolver();

									  multipartResolver.setResolveLazily(this.multipartProperties.isResolveLazily());

									  return multipartResolver;

									 }

可以看出MultipartAutoConfiguration配置类，默认加载的是StandardServletMultipartResolver。

然而，我们往往会在项目中加入commons-fileupload依赖，加载的是CommonsMultipartResolver。此时同时使用两个，会产生冲突。

解决方案

1、使用SpringBoot 默认的StandardServletMultipartResolver，不依赖commons-fileupload。

2、使用commons-fileupload的CommonsMultipartResolver，

排除默认

				?

									spring:

									  autoconfigure:

									    exclude: org.springframework.boot.autoconfigure.web.servlet.MultipartAutoConfiguration

自定义文件解析对象

				?

									@Bean(name = "multipartResolver")

									public MultipartResolver multipartResolver() {

									    CommonsMultipartResolver resolver = new CommonsMultipartResolver();

									    resolver.setDefaultEncoding("UTF-8");

									    return resolver;

									}