数据导出生成Excel附件使用POI的HSSFWorkbook对象

比较常用的实现Java导入、导出Excel的技术有两种Jakarta POI和Java Excel。
Jakarta POI 是一套用于访问微软格式文档的Java API。Jakarta POI有很多组件组成，其中有

用于操作Excel格式文件的HSSF

和用于操作Word的HWPF，

目前用于操作Excel的HSSF比较成熟

一、前端

1、

<el-button type="primary" size="medium" @click="exportExcell">数据导出</el-button>

2、

//数据导出
        exportExcel:function () {
            let self = this;
            self.table.pageData.pollutionIds=[];
            self.table.pageData.caseSourceIds=[];
            this.tagBoxList.forEach(function (item) {
                if(item.type === 0 && item.value){
                    self.table.pageData.pollutionIds.push(item.value);
                }
            });
            if (self.datetimeRange) {
                self.table.pageData.startDate = this.datetimeRange[0];
                self.table.pageData.endDate = this.datetimeRange[1];
            } else {
                self.table.pageData.startDate='' ;
                self.table.pageData.endDate='' ;
            }
            // 按钮事件直接访问接口地址，后面url传参数
            window.location.href= appPath+"/service/xfxxx/exportExcel?ticketId="+self.ticketId +
                "&dataRange="+self.table.pageData.dataRange+"
        }

二、java代码

控制器（业务管理层）：

　　 @ResponseBody
    @RequestMapping(value = "/exportExcel")
    public void exportExcel(HttpServletResponse response, XfxxxParam param, XfUser user) {
        JsonResult json = JsonResult.getSuccessResult();
        try {
            String fileName = "导出数据" + XfDateUtil.DateToString(CacheHelper.getTime(), XfDateUtil.YYYY_MM_DD) + ".xls";
            HSSFWorkbook wb = xxxService.exportExcel(param, user);
            try {
                response.setCharacterEncoding("UTF-8");
                response.setContentType("application/vnd.ms-excel");
                response.setHeader("content-disposition", "attachment;filename=" + new String(fileName.getBytes("utf-8"), "ISO-8859-1") +".xls");
                ExportExcel.setResponseHeader(response, fileName);
                OutputStream os = response.getOutputStream();
                wb.write(os);
                os.flush();
                os.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        } catch (Exception e) {
            logger.error("导出数据报表时异常", e);
            json.setException(e);
        }
    }

业务实施层：

@Override
    public HSSFWorkbook exportxxx(XfxxxParam param, XfUser user) {
        calculatexxxCondition(param);
        List<XfxxxModel> xxxModelList = null;
        xxxModelList = baseMapper.listxxx(param); // mapper接口mybatis交互数据库返回满足条件的数据

        String[] title = {"案件编号", "案件来源", "污染类型", "问题属地", "投诉对象", "问题描述", "举报时间", "要求结办时间", "状态"}; // excel的表头
        String sheetName = "案件数据";
        String[][] content = new String[xxxModelList.size()][];
        for (int i = 0; i < xxxModelList.size(); i++) {
            content[i] = new String[title.length];
            XfxxxModel xxxModel = xxxModelList.get(i);
            content[i][0] = xxxModel.getCaseCode();
            content[i][1] = xxxModel.getCaseSource();
            content[i][2] = xxxModel.getPollutionCtg();
            content[i][3] = xxxModel.getCantonName();
            content[i][4] = xxxModel.getInstName();
            content[i][5] = xxxModel.getxxxReason();
            if (Objects.nonNull(xxxModel.getTime())) {
//                content[i][6] = XfDateUtil.DateToString(xxxModel.getTime(), XfDateUtil.YYYY_MM_DD_HHMMSS);
                content[i][6] = XfDateUtil.DateToString(xxxModel.getTime(), XfDateUtil.YYYY_MM_DD);//带上时分秒excel解析月份会有问题（出现月份大于12的情况）
            }
            if (Objects.nonNull(xxxModel.getInputEndDate())) {
                content[i][7] = XfDateUtil.DateToString(xxxModel.getInputEndDate(), XfDateUtil.YYYY_MM_DD);
            }
            content[i][8] = xxxModel.getBusiName();
        }

        //创建HSSFWorkbook
        HSSFWorkbook wb = ExportExcel.getHSSFWorkbook(sheetName, title, content, null);
        return wb;
    }

封装的导出excel的工具类;

package com.xxx.common.util;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;

import javax.servlet.http.HttpServletResponse;
import java.io.UnsupportedEncodingException;

public class ExportExcel {

    /**
     * 导出Excel
     *
     * @param sheetName sheet名称
     * @param title     标题
     * @param values    内容
     * @param wb        HSSFWorkbook对象
     * @return
     */
    public static HSSFWorkbook getHSSFWorkbook(String sheetName, String[] title, String[][] values, HSSFWorkbook wb) {

        // 第一步，创建一个HSSFWorkbook，对应一个Excel文件
        if (wb == null) {
            wb = new HSSFWorkbook();
        }

        // 第二步，在workbook中添加一个sheet,对应Excel文件中的sheet
        HSSFSheet sheet = wb.createSheet(sheetName);

        // 第三步，在sheet中添加表头第0行,注意老版本poi对Excel的行数列数有限制
        HSSFRow row = sheet.createRow(0);

        // 第四步，创建单元格，并设置值表头 设置表头居中
        HSSFCellStyle style = wb.createCellStyle();
        style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 创建一个居中格式

        //声明列对象
        HSSFCell cell = null;

        //创建标题
        for (int i = 0; i < title.length; i++) {
            cell = row.createCell(i);
            cell.setCellValue(title[i]);
            cell.setCellStyle(style);
        }

        //创建内容
        for (int i = 0; i < values.length; i++) {
            row = sheet.createRow(i + 1);
            for (int j = 0; j < values[i].length; j++) {
                //将内容按顺序赋给对应的列对象
                row.createCell(j).setCellValue(values[i][j]);
            }
        }
        return wb;
    }

    public static void setResponseHeader(HttpServletResponse response, String fileName) {
        try {
            try {
                fileName = new String(fileName.getBytes(), "ISO8859-1");
            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
            }
            response.setContentType("application/octet-stream;charset=ISO8859-1");
            response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
            response.addHeader("Pargam", "no-cache");
            response.addHeader("Cache-Control", "no-cache");
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

}