springmvc之文件上传MultipartResolver

1.介绍

springmvc提供了MultipartResolver来实现文件的上传。其实现类为CommonsMultipartResolver。springmvc默认是没有配置MultipartResolver的。如果想要使用那么就需要在springmvc的上下文配置文件里配置。

2.实例

搭建环境：

<dependencies>    <dependency>      <groupId>junit</groupId>      <artifactId>junit</artifactId>      <version>4.11</version>      <scope>test</scope>    </dependency>    <dependency>    <groupId>commons-logging</groupId>    <artifactId>commons-logging</artifactId>    <version>1.1.3</version></dependency><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-core</artifactId>    <version>4.0.5.RELEASE</version></dependency><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-context</artifactId>    <version>4.0.5.RELEASE</version></dependency><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-beans</artifactId>    <version>4.0.5.RELEASE</version></dependency><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-expression</artifactId>    <version>4.0.5.RELEASE</version></dependency><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-webmvc</artifactId>    <version>4.0.5.RELEASE</version></dependency><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-web</artifactId>    <version>4.0.5.RELEASE</version></dependency><dependency>    <groupId>org.springframework</groupId>    <artifactId>spring-tx</artifactId>    <version>4.0.5.RELEASE</version></dependency>        <dependency>    <groupId>commons-logging</groupId>    <artifactId>commons-logging</artifactId>    <version>1.1.1</version></dependency><dependency>    <groupId>org.hibernate</groupId>    <artifactId>hibernate-validator</artifactId>    <version>4.3.0.Final</version></dependency><dependency>    <groupId>org.jboss.logging</groupId>    <artifactId>jboss-logging</artifactId>    <version>3.1.0.CR2</version></dependency><dependency>    <groupId>javax.validation</groupId>    <artifactId>validation-api</artifactId>    <version>1.0.0.GA</version></dependency><dependency>    <groupId>com.fasterxml.jackson.core</groupId>    <artifactId>jackson-databind</artifactId>    <version>2.6.4</version></dependency><dependency>    <groupId>com.fasterxml.jackson.core</groupId>    <artifactId>jackson-core</artifactId>    <version>2.6.4</version></dependency><dependency>    <groupId>com.fasterxml.jackson.core</groupId>    <artifactId>jackson-annotations</artifactId>    <version>2.6.4</version></dependency><dependency>    <groupId>commons-fileupload</groupId>    <artifactId>commons-fileupload</artifactId>    <version>1.2.1</version></dependency><dependency>    <groupId>commons-io</groupId>    <artifactId>commons-io</artifactId>    <version>2.2</version></dependency>  </dependencies>

后面两个包是文件上传必须的，前面有些包可能多余。

配置springmvc-servlet.xml配置文件：

<context:component-scan base-package="cn.spy"></context:component-scan><!-- 视图解析器 --><beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"><beans:property name="prefix" value="/WEB-INF/"></beans:property><beans:property name="suffix" value=".jsp"></beans:property></beans:bean><beans:bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"><beans:property name="defaultEncoding" value="UTF-8"></beans:property><beans:property name="maxUploadSize" value="1024000"></beans:property></beans:bean>

配置文件里面配置了文件上传需要的CommonsMultipartResolver。配置属性上传的默认编码为UTF-8。上传文件大小为1M。

编写控制器：

@RequestMapping("/viewResolver")@Controllerpublic class ViewResolver {@RequestMapping("/testFileUpload")public String testFileUpload(@RequestParam("desc") String desc,@RequestParam("file") MultipartFile file) throws IOException{System.out.println("desc:"+desc);System.out.println("file:"+file.getOriginalFilename());System.out.println("inputStream"+file.getInputStream());return "result";}}

页面：

<form action="viewResolver/testFileUpload" method="post" enctype="multipart/form-data">    File：<input type="file" name="file"/><br>    desc：<input type="text" name="desc"/><br>    <input type="submit" value="提交"/></form>

结果：

上传结果，转发页面：

后台打印上传文件的原名称及打印文件的输入流