Java后端下载EXCEL模板

package com.cbb.service;

import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.multipart.MultipartFile;

import com.cbb.entity.Card;

public interface CardService {

    
    void downLoadExport(HttpServletResponse response, HttpServletRequest request);

}

实现类imple

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;

import com.cbb.entity.ImportCard;
import com.cbb.mapper.ImportCardMapper;
import com.cbb.service.ImportCardService;
import com.cbb.util.ExcelUtils;

import lombok.RequiredArgsConstructor;

@Service
@RequiredArgsConstructor(onConstructor = @__(@Autowired))
public class ImportCardServiceImple implements ImportCardService {

    @Override
    public List> uploadExcel(MultipartFile file, HttpServletRequest request,
            HttpServletResponse response) {
        if (file.isEmpty()) {
            try {
                throw new Exception("文件不存在！");
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        InputStream in = null;
        try {
            in = file.getInputStream();
        } catch (IOException e) {
            e.printStackTrace();
        }
        List> listob = null;
        try {
            listob = new ExcelUtils().getBankListByExcel(in, file.getOriginalFilename());

        } catch (Exception e) {
            e.printStackTrace();
        }
        return listob;

    }
 

}

    @RequestMapping("downLoadExportCard")
    public void downLoadExport(HttpServletResponse response, HttpServletRequest request) {
        cardService.downLoadExport(response, request);
    }