content: package com.alibaba.easyexcel.test.demo.web;
  
  import java.io.IOException;
  import java.net.URLEncoder;
  import java.util.Date;
  import java.util.List;
  import java.util.Map;
  
  import javax.servlet.http.HttpServletResponse;
  
  import com.alibaba.excel.EasyExcel;
  import com.alibaba.excel.util.ListUtils;
  import com.alibaba.excel.util.MapUtils;
  import com.alibaba.fastjson2.JSON;
  
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.stereotype.Controller;
  import org.springframework.web.bind.annotation.GetMapping;
  import org.springframework.web.bind.annotation.PostMapping;
  import org.springframework.web.bind.annotation.ResponseBody;
  import org.springframework.web.multipart.MultipartFile;
  
  /**
   * web读写案例
   *
   * @author Jiaju Zhuang
   **/
  @Controller
  public class WebTest {
  
      @Autowired
      private UploadDAO uploadDAO;
  
      /**
       * 文件下载（失败了会返回一个有部分数据的Excel）
       * <p>
       * 1. 创建excel对应的实体对象 参照{@link DownloadData}
       * <p>
       * 2. 设置返回的 参数
       * <p>
       * 3. 直接写，这里注意，finish的时候会自动关闭OutputStream,当然你外面再关闭流问题不大
       */
      @GetMapping("download")
      public void download(HttpServletResponse response) throws IOException {
          // 这里注意 有同学反应使用swagger 会导致各种问题，请直接用浏览器或者用postman
          response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
          response.setCharacterEncoding("utf-8");
          // 这里URLEncoder.encode可以防止中文乱码 当然和easyexcel没有关系
          String fileName = URLEncoder.encode("测试", "UTF-8").replaceAll("\\+", "%20");
          response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + fileName + ".xlsx");
  
          EasyExcel.write(response.getOutputStream(), DownloadData.class).sheet("模板").doWrite(data());
      }
  
      /**
       * 文件下载并且失败的时候返回json（默认失败了会返回一个有部分数据的Excel）
       *
       * @since 2.1.1
       */
      @GetMapping("downloadFailedUsingJson")
      public void downloadFailedUsingJson(HttpServletResponse response) throws IOException {
          // 这里注意 有同学反应使用swagger 会导致各种问题，请直接用浏览器或者用postman
          try {
              response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
              response.setCharacterEncoding("utf-8");
              // 这里URLEncoder.encode可以防止中文乱码 当然和easyexcel没有关系
              String fileName = URLEncoder.encode("测试", "UTF-8").replaceAll("\\+", "%20");
              response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + fileName + ".xlsx");
              // 这里需要设置不关闭流
              EasyExcel.write(response.getOutputStream(), DownloadData.class).autoCloseStream(Boolean.FALSE).sheet("模板")
                  .doWrite(data());
          } catch (Exception e) {
              // 重置response
              response.reset();
              response.setContentType("application/json");
              response.setCharacterEncoding("utf-8");
              Map<String, String> map = MapUtils.newHashMap();
              map.put("status", "failure");
              map.put("message", "下载文件失败" + e.getMessage());
              response.getWriter().println(JSON.toJSONString(map));
          }
      }
  
      /**
       * 文件上传
       * <p>
       * 1. 创建excel对应的实体对象 参照{@link UploadData}
       * <p>
       * 2. 由于默认一行行的读取excel，所以需要创建excel一行一行的回调监听器，参照{@link UploadDataListener}
       * <p>
       * 3. 直接读即可
       */
      @PostMapping("upload")
      @ResponseBody
      public String upload(MultipartFile file) throws IOException {
          EasyExcel.read(file.getInputStream(), UploadData.class, new UploadDataListener(uploadDAO)).sheet().doRead();
          return "success";
      }
  
      private List<DownloadData> data() {
          List<DownloadData> list = ListUtils.newArrayList();
          for (int i = 0; i < 10; i++) {
              DownloadData data = new DownloadData();
              data.setString("字符串" + 0);
              data.setDate(new Date());
              data.setDoubleData(0.56);
              list.add(data);
          }
          return list;
      }
  }
  