java导出excel表格

公司自己定义的list类型，我就不贴了，大家替换一下就可以

package com.example.demo.Dao;


import org.apache.poi.hssf.usermodel.*;

import java.io.File;
import java.io.FileOutputStream;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;

public class ExcelUtil {
    public static String formatToday(String format) {
        format = format != null && format.trim().length() != 0 ? format : "yyyy-MM-dd";
        SimpleDateFormat formater = new SimpleDateFormat(format);
        return formater.format(new Date());
    }

    //时间格式化为文件名
    public String getExportDate() {
        return formatToday("-yyyyMMddHHmmss");
    }

    /**
     * 导出方法
     *
     * @param list
     * @return
     */
    public String excel(PagedList list) {
        String path = "D:/upload/";
        File file = new File(path);
        //文件夹路径是否存在，不存在则新建
        if (!file.exists()) {
            file.mkdirs();
        }
        //导出路径
        String filepath = path + "购买清单" + this.getExportDate() + ".xls";
        // 创建一个webbook，对应一个Excel文件
        HSSFWorkbook wb = new HSSFWorkbook();
        // 在webbook中添加一个sheet,对应Excel文件中的sheet
        HSSFSheet sheet = wb.createSheet("购买清单");
        // 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short
        HSSFRow row = sheet.createRow((int) 0);
        // 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
        //创建列标题
        HSSFCell cell = row.createCell((short) 0);
        cell.setCellValue("订单编号");
        cell.setCellStyle(style);
        //设置位置、宽度
        sheet.setColumnWidth(0, 6000);
        cell = row.createCell((short) 1);
        cell.setCellValue("订单日期");
        cell.setCellStyle(style);
        sheet.setColumnWidth(1, 4500);
        cell = row.createCell((short) 2);
        cell.setCellValue("购买量");
        cell.setCellStyle(style);
        cell = row.createCell((short) 3);
        cell.setCellValue("市场价");
        cell.setCellStyle(style);
        sheet.setColumnWidth(3, 3500);
        cell = row.createCell((short) 4);
        cell.setCellValue("执行价");
        cell.setCellStyle(style);
        sheet.setColumnWidth(4, 3500);
        cell = row.createCell((short) 5);
        cell.setCellValue("金额");
        cell.setCellStyle(style);
        sheet.setColumnWidth(5, 3500);

        long totalBuyQty = 0;
        double totalSkuPrice = 0;
        double totalBuyPrice = 0;
        double goodsSumAmount = 0;

        for (int i = 0; i < list.getRows().size() + 1; i++) {

            row = sheet.createRow(i + 1);
            //订单列表结束最后一行添加合计
            List<Order> order = list.getRows();
            //不需要合计可忽略此段
            if (list.getRows().size() == i) {
                row.createCell((short) 2).setCellValue("总计：");
                row.createCell((short) 3).setCellValue("购买量：" + totalBuyQty);
                row.createCell((short) 4).setCellValue("金额：" + goodsSumAmount);
                row.createCell((short) 5).setCellValue("节省金额：" + (totalSkuPrice - totalBuyPrice));
                continue;
            }
            totalBuyQty += order.get(i).getBuyQty();//获取总购买量
            totalSkuPrice += order.get(i).getMaxPrice() * order.get(i).getBuyQty();//获取总市场价
            totalBuyPrice += order.get(i).getBuyPrice() * order.get(i).getBuyQty();//获取总购买价格
            goodsSumAmount += order.get(i).getGoodsSumAmount();//获取产品总价


            // 创建单元格，并设置值
            row.createCell((short) 0).setCellValue(order.get(i).getOrderNo());
            row.createCell((short) 1).setCellValue(new SimpleDateFormat("yyyy-MM-dd").format(order.get(i).getOrderTime()));
            row.createCell((short) 2).setCellValue(order.get(i).getBuyQty());
            row.createCell((short) 3).setCellValue(order.get(i).getMaxPrice());
            row.createCell((short) 4).setCellValue(order.get(i).getBuyPrice());
            row.createCell((short) 5).setCellValue(order.get(i).getGoodsSumAmount());

        }

        // 将文件存到指定位置
        try {
            FileOutputStream fout = new FileOutputStream(filepath);
            wb.write(fout);
            fout.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        //返回路径给前端，前端提供下载
        String fileUrl = "D:/upload/购买清单" + this.getExportDate() + ".xls";
        return fileUrl;
    }
}

实体如下：

package com.example.demo.Dao;

import java.io.Serializable;
import java.sql.Timestamp;

/**
 * 购买清单实体
 */
public class Order implements Serializable {
    private String orderNo;//编号
    private Timestamp orderTime;//时间
    private long buyQty;//购买数量
    private double buyPrice;//购买时价格
    private double maxPrice;//市场价
    private double goodsSumAmount;//sku价格

    public String getOrderNo() {
        return orderNo;
    }

    public void setOrderNo(String orderNo) {
        this.orderNo = orderNo;
    }

    public Timestamp getOrderTime() {
        return orderTime;
    }

    public void setOrderTime(Timestamp orderTime) {
        this.orderTime = orderTime;
    }

    public long getBuyQty() {
        return buyQty;
    }

    public void setBuyQty(long buyQty) {
        this.buyQty = buyQty;
    }

    public double getBuyPrice() {
        return buyPrice;
    }

    public void setBuyPrice(double buyPrice) {
        this.buyPrice = buyPrice;
    }

    public double getMaxPrice() {
        return maxPrice;
    }

    public void setMaxPrice(double maxPrice) {
        this.maxPrice = maxPrice;
    }

    public double getGoodsSumAmount() {
        return goodsSumAmount;
    }

    public void setGoodsSumAmount(double goodsSumAmount) {
        this.goodsSumAmount = goodsSumAmount;
    }
}