POI实现Excel导出

<dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>3.9</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>3.9</version>
        </dependency>

引入依赖之后，页面点击导出按钮，触发js请求后台导出的逻辑，js代码如下：

 let paramData = 'flowType=' + this.searchData.flowType;
 window.open('/api/chargeFlow/exportSupplierData?' + paramData);

js请求到的后台controller代码如下：

@RestController
@RequestMapping(value = "/api/chargeFlow")
public class SupplierController {
    @Resource
    private ExportSupplierDataService exportSupplierDataService;

    @RequestMapping(value = "exportSupplierDailyGroupBill")
    public String exportSupplierDailyGroupBill(HttpServletRequest request) {
        exportSupplierDataService.execute(request);
        return null;
    }

}

execute方法如下：

protected void execute(HttpServletRequest request) {
        String flowType = request.getParameter("flowType");
        HttpServletResponse response = getCrrentResponse();
        if (response == null) {
            bizContextVo.setErrorMsgVo(ErrorUtils.buildExceptionVo("", "获取response失败！"));
            return;
        }
        Workbook workbook = null;
        //根据flowType查询数据库获取数据List<SupplierVo> supplierVos
        workbook=processData2WorkBook(supplierVos);
        if (workbook == null) {
            //Excel文件构建失败！
            return;
        }
        OutputStream outputStream = null;
        try {
            outputStream = response.getOutputStream();
            response.reset();
            // 文件名称
            String fileName = '供货商数据导出' + DateUtils.formatDate(new Date(), DateUtils.DATE_FORMAT_YYYYMMDDHHMMSS) + ".xls";
            fileName = new String(fileName.getBytes("UTF-8"), "ISO8859-1");
            // 设定输出文件头
            response.setHeader("Content-disposition", "attachment; filename=" + fileName);
            // 定义输出类型
            response.setContentType("application/msexcel");
            workbook.write(outputStream);
        } catch (Exception e) {
            //Excel文件导出失败！
        } finally {
            try {
                if (outputStream != null) {
                    outputStream.flush();
                    outputStream.close();
                }
            } catch (IOException e) {
                //Excel文件流关闭失败！
            }
        }

    }

 private Workbook processData2WorkBook(List<SupplierVo> data) {
        HSSFWorkbook workbook = new HSSFWorkbook();
        HSSFSheet sheet = workbook.createSheet();
        if (CollectionUtils.isEmpty(data)) {
            return workbook;
        }
        sheet.setDefaultRowHeightInPoints(18);
        // 表头单元格样式
        HSSFCellStyle titleStyle = workbook.createCellStyle();
        // 自动换行
        titleStyle.setWrapText(true);
        titleStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        titleStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
        HSSFFont font = workbook.createFont();
        font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
        titleStyle.setFont(font);

        // 文本单元格样式
        HSSFCellStyle style = workbook.createCellStyle();
        // 自动换行
//        style.setWrapText(true);
        style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);

        // 创建表头
        HSSFRow firstRow = sheet.createRow(0);
        for (int i = 0; i < 3; i++) {
            HSSFCell cell = firstRow.createCell(i);
            cell.setCellStyle(titleStyle);
            cell.setCellValue("列名称"+i);
            sheet.setColumnWidth(i, 3000);
        }   

  int dataRowNum = 1
  for (SupplierVo supplierVo : data) {
     if (supplierVo == null) { 
       continue; 
      } 
   HSSFRow dataRow = sheet.createRow(dataRowNum++); 
   createCell(sheet, dataRow, style, 0, supplierVo.getName()); 
   createCell(sheet, dataRow, style, 1, supplierVo.getPrice()); 
   createCell(sheet, dataRow, style, 2, supplierVo.getNum()); 
   } } } 
   return workbook; } 
   /** 
   * 获取当前response 
   * * @return */ 
   private HttpServletResponse getCrrentResponse() {
   ServletRequestAttributes servletRequestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes(); 
   if (servletRequestAttributes == null) { 
       return null; 
   } 
   HttpServletResponse response = servletRequestAttributes.getResponse(); 
   return response; 
   } 
   /** 
   * 创建列 
   * * @param row
   * @param cellIndex 
   * @param value 
   */ 
   public void createCell(HSSFSheet sheet, HSSFRow row, HSSFCellStyle style, int cellIndex, Object value) {
   HSSFCell cell = null; 
   if (null == value) { 
   row.createCell(cellIndex, HSSFCell.CELL_TYPE_BLANK);
   } else { 
   String tempValue = value.toString(); 
   cell = row.createCell(cellIndex);
   cell.setCellValue(tempValue); cell.setCellStyle(style); 
   // 设置列宽
   if (StringUtils.isNotBlank(tempValue)) { 
   int valueWidth = tempValue.getBytes().length * 256; 
   int columnWidth = sheet.getColumnWidth(cellIndex); 
   if (valueWidth > columnWidth) { 
   sheet.setColumnWidth(cellIndex, valueWidth); 
   } } } }