项目实战之poi导出excel

所需jar包

官方下载地址：http://mirrors.hust.edu.cn/apache/poi/release/bin/poi-bin-3.17-20170915.zip

1.前端调用方法：

2.action入口方法：

public void lackExamineeExportExcel() {
        try{
            ArrayList fieldData  = this.resultExamineeServiceImpl.listResultExamineeByIsProcess();
            ArrayList<String> fieldName  = this.resultExamineeServiceImpl.getExcelName();
            OutputStream os = this.getResponse().getOutputStream(); // 取得输出流
            String fileName = System.currentTimeMillis()+"缺勤人员信息表.xls";
            fileName = FileUtils.encodeFilename(fileName, getRequest());
            this.getResponse().reset(); // 清空输出流
            this.getResponse().setContentType("application/vnd.ms-excel"); // 定义输出类型
            this.getResponse().setHeader("Content-disposition", "attachment;filename=" + new String(fileName.getBytes("UTF-8"), "ISO8859-1"));// 中文问题
            ExcelFileGenerator xlsExportBean = new ExcelFileGenerator(fieldName, fieldData);
            xlsExportBean.expordExcel(os); // 调用生成Excel文件bean
            System.setOut(new PrintStream(os));
            os.flush();
            if (os != null){
                os.close();
            }
        }catch(Exception e) {
            throw new RuntimeException("导出错误");
        }
    }

3.业务层方法

public ArrayList<String> getExcelName() {
        ArrayList<String> rsList = new ArrayList();
        String[] strArray = {"院系名称","姓名","性别","学号","一级学科代码","一级学科名称","专业代码","专业名称"};
        if (strArray.length > 0) {
            for (int i = 0; i < strArray.length; i++) {
                rsList.add(strArray[i]);
            }
        }
        return rsList;
    }
    public ArrayList listResultExamineeByIsProcess() {
        List<ResultExaminee1> resultExaminee1List = this.resultExaminee1DAO.findByProperty("isProcess", false);
        ArrayList dataList = new ArrayList();
        if (null != resultExaminee1List && resultExaminee1List.size()>0) {
            for (ResultExaminee1 resultExaminee1 : resultExaminee1List) {
                List tempList=new ArrayList();
　　　　　　　　　// 数据顺序应该跟字段顺序保持一致
                tempList.add(resultExaminee1.getCollegeName());
                tempList.add(resultExaminee1.getExamineeName());
                tempList.add(resultExaminee1.getExamineeSex());
                tempList.add(resultExaminee1.getLicence());
                tempList.add(resultExaminee1.getSubjectCode());
                tempList.add(resultExaminee1.getSubjectName());
                tempList.add(resultExaminee1.getSpecialtyCode());
                tempList.add(resultExaminee1.getSpecialtyName());
                //tempList.add(resultExaminee1.getCreateDate());
                dataList.add(tempList);
            }
            return dataList;
        }
        return dataList;
    }

4.设置下载文件中文件的名称FileUtils

import java.net.URLEncoder;
import java.util.regex.Pattern;

import org.apache.commons.fileupload.util.mime.MimeUtility;
import org.apache.commons.lang.StringUtils;  

/**  
     * 设置下载文件中文件的名称
     *
     * @param filename
     * @param request
     * @return
     */
    public static String encodeFilename(String fileName, HttpServletRequest request) {
      /**
       * 获取客户端浏览器和操作系统信息
       * 在IE浏览器中得到的是：User-Agent=Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; Maxthon; Alexa Toolbar)
       * 在Firefox中得到的是：User-Agent=Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.7.10) Gecko/20050717 Firefox/1.0.6
       */
      String agent = request.getHeader("USER-AGENT");
      try {
        if ((agent != null) && (-1 != agent.indexOf("MSIE"))) {
          String newFileName = URLEncoder.encode(fileName, "UTF-8");
          newFileName = StringUtils.replace(newFileName, "+", "%20");
          if (newFileName.length() > 150) {
            newFileName = new String(fileName.getBytes("GB2312"), "ISO8859-1");
            newFileName = StringUtils.replace(newFileName, " ", "%20");
          }
          return newFileName;
        }
        if ((agent != null) && (-1 != agent.indexOf("Mozilla")))
          return MimeUtility.decodeText(fileName);    

        return fileName;
      } catch (Exception ex) {
        return fileName;
      }
    }
}

5.核心工具类ExcelFileGenerator

/**
 * 系统数据导出Excel 生成器
 * @version 1.0
 */
package com.sinotn.utils;

import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;
/**
 * @Description  Excel导出
 * @Copyright: Copyright (c) 2018 Company:
 * @author Libin
 * @date 2018年2月1日 上午11:09:38
 * @version V1.0
 */
public class ExcelFileGenerator {

    private final int SPLIT_COUNT = 1000; //Excel每个工作簿的行数

    private ArrayList<String> fieldName = null; //excel标题数据集

    private List<List<String>> fieldData = null; //excel数据内容    

    private HSSFWorkbook workBook = null;

    /**
     * 构造器
     * @param fieldName 结果集的字段名
     * @param data
     */
    public ExcelFileGenerator(ArrayList<String> fieldName, ArrayList<List<String>> fieldData) {

        this.fieldName = fieldName;
        this.fieldData = fieldData;
    }

    /**
     * 创建HSSFWorkbook对象
     * @return HSSFWorkbook
     */
    public HSSFWorkbook createWorkbook() {

        workBook = new HSSFWorkbook();//创建一个工作薄对象
        int rows = fieldData.size();//总的记录数
        int sheetNum = 0;           //指定sheet的页数

        if (rows % SPLIT_COUNT == 0) {
            sheetNum = rows / SPLIT_COUNT;
        } else {
            sheetNum = rows / SPLIT_COUNT + 1;
        }

        for (int i = 1; i <= sheetNum; i++) {//循环2个sheet的值
            HSSFSheet sheet = workBook.createSheet("Page " + i);//使用workbook对象创建sheet对象
            HSSFRow headRow = sheet.createRow((short) 0); //创建行，0表示第一行（本例是excel的标题）
            for (int j = 0; j < fieldName.size(); j++) {//循环excel的标题
                HSSFCell cell = headRow.createCell( j);//使用行对象创建列对象，0表示第1列
                /**************对标题添加样式begin********************/

                //设置列的宽度/
                sheet.setColumnWidth(j, 6000);
                HSSFCellStyle cellStyle = workBook.createCellStyle();//创建列的样式对象
                HSSFFont font = workBook.createFont();//创建字体对象
                //字体颜色变红
                font.setColor(HSSFColor.RED.index);
                font.setFontHeightInPoints((short) 16);//设置字体大小
                //如果font中存在设置后的字体，并放置到cellStyle对象中，此时该单元格中就具有了样式字体
                cellStyle.setFont(font);

                /**************对标题添加样式end********************/

                //添加样式
                cell.setCellType(HSSFCell.CELL_TYPE_STRING);
                if(fieldName.get(j) != null){
                    //将创建好的样式放置到对应的单元格中
                    cell.setCellStyle(cellStyle);
                    cell.setCellValue((String) fieldName.get(j));//为标题中的单元格设置值
                }else{
                    cell.setCellValue("-");
                }
            }
            //分页处理excel的数据，遍历所有的结果
            for (int k = 0; k < (rows < SPLIT_COUNT ? rows : SPLIT_COUNT); k++) {
                if (((i - 1) * SPLIT_COUNT + k) >= rows)//如果数据超出总的记录数的时候，就退出循环
                    break;
                HSSFRow row = sheet.createRow((short) (k + 1));//创建1行
                //分页处理，获取每页的结果集，并将数据内容放入excel单元格
                ArrayList<String> rowList = (ArrayList<String>) fieldData.get((i - 1) * SPLIT_COUNT + k);
                for (int n = 0; n < rowList.size(); n++) {//遍历某一行的结果
                    HSSFCell cell = row.createCell( n);//使用行创建列对象
                    if(rowList.get(n) != null){
                        cell.setCellValue((String) rowList.get(n).toString());
                    }else{
                        cell.setCellValue("");
                    }
                }
            }
        }
        return workBook;
    }

    public void expordExcel(OutputStream os) throws Exception {
        workBook = createWorkbook();
        workBook.write(os);//将excel中的数据写到输出流中，用于文件的输出
        os.close();
    }

}