web开发中，一个系统的普通需求也包含导出excel，一般採用POI做统计报表导出excel。

导出excel工具类：

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.List;

import java.util.Map;

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

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

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

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

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

public class ExportExcel {

	private ExportExcel() {

		super();

	}

	public static void exportExcel(List<Object> list, Map<Integer, Long> map,

			String[] titles) throws IOException {

		// 创建Excel文档

		HSSFWorkbook hwb = new HSSFWorkbook();

		// sheet 相应一个工作页

		HSSFSheet sheet = hwb.createSheet("exportReport");

		int colNum = titles.length;

		// 创建第一行

		HSSFRow firstrow = sheet.createRow(0);

		HSSFCell[] firstcell = new HSSFCell[colNum];

		for (int col = 0; col < colNum; col++) {

			firstcell[col] = firstrow.createCell(col);

			firstcell[col].setCellValue(new HSSFRichTextString(titles[col]));

		}

		// 插入记录

		int rowNum = map.size();

		for (int i = 0; i < rowNum; i++) {

			// 从第二行開始

			HSSFRow row = sheet.createRow(i + 1);

			// 插入list中的字段

			for (int col = 0; col < colNum - 2; col++) {

				HSSFCell cell = row.createCell(col);

				cell.setCellValue(list.get(col).toString());

			}

			// 插入月份或日期

			row.createCell(colNum - 2).setCellValue(i + 1);

			// 插入总量

			row.createCell(colNum - 1).setCellValue(map.get(i + 1));

		}

		String fileName = titles[1].substring(0, 2);

		if (colNum == 4) {

			fileName += list.get(0) + "_" + list.get(1) + "年_年度报表";

		} else if (colNum == 5) {

			fileName += list.get(0) + "_" + list.get(1) + "年" + list.get(2)

					+ "月_月度报表";

		}

		// 创建文件输出流，准备输出电子表格

		OutputStream out = new FileOutputStream("../webapps/UsedMallMinaServer/files/"

				+ fileName + ".xls");

		hwb.write(out);

		out.close();

	}

}