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();
}
}}
