SpringBoot之文件下载

 package org.springboot.controller;

 import org.springboot.constant.Constant;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.RequestMapping;

 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import java.io.*;
 import java.net.URLEncoder;

 /**
  * @Auther:GongXingRui
  * @Date:2018/12/24
  * @Description:
  **/
 @Controller
 public class FileDownload {

         //实现Spring Boot 的文件下载功能，映射网址为/download
         @RequestMapping("/download")
         public String downloadFile(HttpServletRequest request,
                                    HttpServletResponse response) throws UnsupportedEncodingException {
 //            String picPath = "C:/Temp/pic";
             String picPath = Constant.CONFIG_PROPERTIES.getProperty("download.path");

             // 获取指定目录下的第一个文件
             File scFileDir = new File(picPath);
             File TrxFiles[] = scFileDir.listFiles();
             System.out.println(TrxFiles[0]);
             String fileName = TrxFiles[0].getName(); //下载的文件名

             // 如果文件名不为空，则进行下载
             if (fileName != null) {
                 //设置文件路径
                 File file = new File(picPath, fileName);

                 // 如果文件名存在，则进行下载
                 if (file.exists()) {
                     // 配置文件下载
                     response.setHeader("content-type", "application/octet-stream");
                     response.setContentType("application/octet-stream");
                     // 下载文件能正常显示中文
                     response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8"));

                     // 实现文件下载
                     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("Download the file successfully!");
                     }
                     catch (Exception e) {
                         System.out.println("Download the file failed!");
                     }
                     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;
         }

 }