详解SpringBoot文件上传下载和多文件上传（图文）

 4.0.0
 SpringWebContent
 SpringWebContent
 war
 1.0-SNAPSHOT
 SpringWebContent Maven Webapp
 http://maven.apache.org
 
  org.springframework.boot
  spring-boot-starter-parent
  1.4.3.RELEASE
 
 
  
   org.springframework.boot
   spring-boot-starter-thymeleaf
  
  
   org.springframework.boot
   spring-boot-devtools
   true
  
  
   junit
   junit
   3.8.1
   test
  
 
 
  1.8
 
 
  SpringWebContent
 
 
  org.springframework.boot
  spring-boot-maven-plugin
 

 

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class Application {

  public static void main(String[] args) {
    SpringApplication.run(Application.class, args);
  }
}

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartHttpServletRequest;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.util.List;

@Controller
public class FileController {
  @RequestMapping("/greeting")
  public String greeting(@RequestParam(value="name", required=false, defaultValue="World") String name, Model model) {
    model.addAttribute("name", name);
    return "greeting";
  }
  private static final Logger logger = LoggerFactory.getLogger(FileController.class);
  //文件上传相关代码
  @RequestMapping(value = "upload")
  @ResponseBody
  public String upload(@RequestParam("test") MultipartFile file) {
    if (file.isEmpty()) {
      return "文件为空";
    }
    // 获取文件名
    String fileName = file.getOriginalFilename();
    logger.info("上传的文件名为：" + fileName);
    // 获取文件的后缀名
    String suffixName = fileName.substring(fileName.lastIndexOf("."));
    logger.info("上传的后缀名为：" + suffixName);
    // 文件上传后的路径
    String filePath = "E://test//";
    // 解决中文问题，liunx下中文路径，图片显示问题
    // fileName = UUID.randomUUID() + suffixName;
    File dest = new File(filePath + fileName);
    // 检测是否存在目录
    if (!dest.getParentFile().exists()) {
      dest.getParentFile().mkdirs();
    }
    try {
      file.transferTo(dest);
      return "上传成功";
    } catch (IllegalStateException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    }
    return "上传失败";
  }

  //文件下载相关代码
  @RequestMapping("/download")
  public String downloadFile(org.apache.catalina.servlet4preview.http.HttpServletRequest request, HttpServletResponse response){
    String fileName = "FileUploadTests.java";
    if (fileName != null) {
      //当前是从该工程的WEB-INF//File//下获取文件(该目录可以在下面一行代码配置)然后下载到C:\\users\\downloads即本机的默认下载的目录
      String realPath = request.getServletContext().getRealPath(
          "//WEB-INF//");
      File file = new File(realPath, fileName);
      if (file.exists()) {
        response.setContentType("application/force-download");// 设置强制下载不打开
        response.addHeader("Content-Disposition",
            "attachment;fileName=" + fileName);// 设置文件名
        byte[] buffer = new byte[1024];
        FileInputStream fis = null;
        BufferedInputStream bis = null;
        try {
          fis = new FileInputStream(file);
          bis = new BufferedInputStream(fis);
          OutputStream os = response.getOutputStream();
          int i = bis.read(buffer);
          while (i != -1) {
            os.write(buffer, 0, i);
            i = bis.read(buffer);
          }
          System.out.println("success");
        } catch (Exception e) {
          e.printStackTrace();
        } finally {
          if (bis != null) {
            try {
              bis.close();
            } catch (IOException e) {
              e.printStackTrace();
            }
          }
          if (fis != null) {
            try {
              fis.close();
            } catch (IOException e) {
              e.printStackTrace();
            }
          }
        }
      }
    }
    return null;
  }
  //多文件上传
  @RequestMapping(value = "/batch/upload", method = RequestMethod.POST)
  @ResponseBody
  public String handleFileUpload(HttpServletRequest request) {
    List files = ((MultipartHttpServletRequest) request)
        .getFiles("file");
    MultipartFile file = null;
    BufferedOutputStream stream = null;
    for (int i = 0; i  "
              + e.getMessage();
        }
      } else {
        return "You failed to upload " + i
            + " because the file was empty.";
      }
    }
    return "upload successful";
  }

  
  


Get your greeting here

  文件：
  

下载test
多文件上传

  
文件1：
  
文件2：