依赖包

        <!-- POI包 -->
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>3.8</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>3.8</version>
        </dependency>

Controller 层定义

@RestController
public class StdandardDirectoryController {

    /**
     * 下载标准化字典Excel导入模版
     * @return Object 状态码
     */
    @GetMapping("/download/downloadStdDictTemplate")
    @ResponseBody
    public void downloadStdDictTemplate(HttpServletRequest request,HttpServletResponse response) throws Exception{

        log.info("调用/download/downloadStdDictTemplate");

        standardDirectoryService.downloadStdDictTemplate(request,response);

    }
}

service 层接口定义

public interface IStandardDirectoryService {

    /**
     * 下载标准数据Excel模板
     */
    void downloadStdDictTemplate(HttpServletRequest request,HttpServletResponse response) throws Exception;

}

service 层定义

@Service
public class StandardDirectoryServiceImpl implements IStandardDirectoryService {

    /**
     * 下载标准数据Excel模板
     */
    @Override
    public void downloadStdDictTemplate(HttpServletRequest request, HttpServletResponse response) throws Exception{
		/**
		 * 创建文件
		 */
		//文件名
		String fileName = "标准化字典导入模板";
		//设置表头
		String sheetName="标准化字典信息";
		//设置列头
		String[] title = {"IMEI","EID","IMSI","ICCID","MSISDN"};
		// 在内存中创建excel
		XSSFWorkbook workBook = new XSSFWorkbook();
		XSSFSheet sheet = workBook.createSheet(sheetName);
		XSSFRow headRow = sheet.createRow(0);
		for (int i = 0; i < title.length; i++) {
			//设置列宽
			sheet.setColumnWidth(i, 256*13);
			XSSFCell cell = headRow.createCell(i);
			// 添加样式
			cell.setCellType(HSSFCell.CELL_TYPE_STRING);
			if (title[i] != null) {
				cell.setCellValue(title[i]);
			}
		}
		response.addHeader("Content-Disposition", "attachment;filename=" + new String(fileName.getBytes("utf-8"),"ISO-8859-1" )+ ".xls");
		response.setContentType("application/vnd.ms-excel");
		response.setCharacterEncoding("UTF-8");
		OutputStream out = response.getOutputStream();
		workBook.write(out);
		if(out!=null){
			out.flush();
		}
		out.close();

    }

}