SpringMVC如何实现高效文件上传功能？

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Maven 依赖配置，Spring 包及版本：- commons-fileupload: 2.4- commons-io: 1.2.1- 使用 JavaConfig 配置 Spring MVC- 包名：com.amiu.java_config- 导入：org.springframework.web

maven导包，spring的包和下面这两个包

2.4 1.2.1 commons-fileupload commons-fileupload ${fileupload.version} commons-io commons-io ${commons.io.version} javaConfig配置springMVC

package com.amiu.java_config; import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer; public class WebInitializer extends AbstractAnnotationConfigDispatcherServletInitializer{ @Override protected Class [] getRootConfigClasses() { // TODO Auto-generated method stub return new Class[]{MvcConfig.class}; } @Override protected Class [] getServletConfigClasses() { // TODO Auto-generated method stub return null; } @Override protected String[] getServletMappings() { // TODO Auto-generated method stub return new String[]{"/"}; } } MvcConfig

package com.amiu.java_config; import java.io.IOException; import org.apache.log4j.Logger; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.core.io.FileSystemResource; import org.springframework.web.multipart.MultipartResolver; import org.springframework.web.multipart.commons.CommonsMultipartResolver; import org.springframework.web.servlet.config.annotation.EnableWebMvc; import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter; @Configuration @EnableWebMvc @ComponentScan("com.amiu") public class MvcConfig extends WebMvcConfigurerAdapter{ private static final Logger logger = Logger.getLogger(MvcConfig.class); @Bean public MultipartResolver multipartResolver() { CommonsMultipartResolver commonsMultipart = new CommonsMultipartResolver(); commonsMultipart.setDefaultEncoding("UTF-8");//设置字符编码 //commonsMultipart.setMaxUploadSizePerFile(5*1024*1024);//单个文件最大上传限制 commonsMultipart.setMaxUploadSize(20*1024*1024);//设置最大上传大小 try { //设置临时路径 commonsMultipart.setUploadTempDir(new FileSystemResource("/tempImg")); } catch (IOException e) { logger.error(e.getMessage()); e.printStackTrace(); } return commonsMultipart; } @Override public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) { configurer.enable(); } } spring controller

package com.amiu.upload; import java.io.File; import java.io.IOException; import java.util.ArrayList; import java.util.Date; import java.util.List; import javax.annotation.PostConstruct; import org.apache.log4j.Logger; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import org.springframework.web.multipart.MultipartFile; import org.springframework.web.multipart.MultipartHttpServletRequest; @RestController public class ImgController { private static final Logger logger = Logger.getLogger(ImgController.class); //上传最大限制 private long UPLOAD_FILE_MAX_SIZE = 5*1024*1024; private List SUPPORT_IAMGE_SUFFIXList; //被@PostConstruct修饰的方法会在服务器加载Servlet的时候运行， //并且只会被服务器调用一次，类似于Serclet的inti()方法 @PostConstruct void init(){ SUPPORT_IAMGE_SUFFIXList = new ArrayList (); SUPPORT_IAMGE_SUFFIXList.add("jpg"); SUPPORT_IAMGE_SUFFIXList.add("png"); SUPPORT_IAMGE_SUFFIXList.add("jpeg"); SUPPORT_IAMGE_SUFFIXList.add("pdf"); } @RequestMapping(value = "/img") public String uploadPic(MultipartHttpServletRequest request) { System.out.println("in imageUpload"); //只获取image MultipartFile image = request.getFile("image"); if(image == null) return "choice file please"; if(image.getSize() > UPLOAD_FILE_MAX_SIZE) return "file to big,it must smaller than 5M"; String orgFileName = image.getOriginalFilename(); //文件格式后缀 String fileSuffix = orgFileName.substring(orgFileName.indexOf('.')+1).toLowerCase(); //判断文件格式 if(!SUPPORT_IAMGE_SUFFIXList.contains(fileSuffix)) return "unsupport file format"; String path = "E:/image/"; String fileName = new Date().getTime()+fileSuffix; File localFile = new File(path+fileName); try { //spring提供的上传方法 image.transferTo(localFile); } catch (IllegalStateException | IOException e) { logger.error(e.getMessage()); System.out.println(e.getMessage()); e.printStackTrace(); } return "success: "+fileName; } } 页面