Java中Excel文件的批量导入和导出

需要jar包：

后面两个主要是保证Excel2007这个版本的。

 页面提交时别忘了  enctype="multipart/form-data"

package com.jykj.comutils.magenUtils;

import java.io.InputStream;
import java.text.SimpleDateFormat;
import java.util.Date;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFDateUtil;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.springframework.web.multipart.MultipartFile;

public class ExcelUtil {

	/**
	 * Excel导入
	 * @param myFile
	 * @throws Exception
	 */
	public static void getExcel(MultipartFile myFile) throws Exception{
		Workbook workbook = null;
		String filename = myFile.getOriginalFilename();
		InputStream inS = myFile.getInputStream();
		if (filename.endsWith("xls")) {//2003版本
			workbook = new HSSFWorkbook(inS);
		}else if (filename.endsWith("xlsx")) {//2007版本
			workbook = new XSSFWorkbook(inS);
		}else {
			throw new Exception("文件不是Excel文件");
		}
		//如有多个工作薄，workbook.getSheetAt(2);获取第三个工作薄
		Sheet sheet = workbook.getSheet("sheet1");
                //Row row1 = sheet.getRow(0);获取第一行
                //Cell cell = row1.getCell(6);获取第一行第六列信息
		int rows = sheet.getLastRowNum();//获取文件有多少行。不包含第一行
                //如需要获取多少列：sheet.getRow(0).getPhysicalNumberOfCells();这是获取第一行有多少列
		if (rows == 0) {
			throw new Exception("没有数据");
		}
		
		for (int i = 1; i <= rows+1; i++) {
			Row row = sheet.getRow(i);
			if (row != null) {//该行不为空
				Student student = new Student();
				student.setStuId(getCellValue(row.getCell(0)));//第一列数据  学号ID
				student.setStuName(getCellValue(row.getCell(1)));//第二列数据  名称
				student.setStuClass(getCellValue(row.getCell(2)));//第三列数据  班级
			}
		}
	}
	
	public static String getCellValue(Cell cell){
		String value = null;
		if (cell != null) {
			switch (cell.getCellType()) {//判断cell的类型
			case HSSFCell.CELL_TYPE_NUMERIC://数字
				value = cell.getDateCellValue() + "";
				if (HSSFDateUtil.isCellDateFormatted(cell)) {//判断cell是不是时间
					Date date = cell.getDateCellValue();
					if (date != null) {
						value = new SimpleDateFormat("yyyy-MM-dd").format(date);
					}else {
						value = "";
					}
				}
				break;
			case HSSFCell.CELL_TYPE_STRING://字符
				value = cell.getStringCellValue();
				break;
			case HSSFCell.CELL_TYPE_BLANK://空白
				break;
			case HSSFCell.CELL_TYPE_ERROR://错误
				break;
			default:
				break;
			}
		}
		return value;
	}
}

/**
	 * 导出
	 * @param response
	 * @throws IOException
	 */
	public static void exportExcel(HttpServletResponse response) throws IOException{
		//创建一个webbook,对应一个Excel文件
		HSSFWorkbook workbook = new HSSFWorkbook();
		//给Excel文件添加文件簿
		HSSFSheet sheet = workbook.createSheet("Sheet1");
		//给Excel文件添加行
		HSSFRow row = sheet.createRow(0);
		//
		HSSFCellStyle style = workbook.createCellStyle();
		//给第一行添加数据
		HSSFCell cell = row.createCell(0);
		cell.setCellValue("学号");
		cell = row.createCell(1);
		cell.setCellValue("名称");
		row = sheet.createRow(1);
		cell = row.createCell(0);
		cell.setCellValue("10");
		cell = row.createCell(1);
		cell.setCellValue("马亘");
		OutputStream output = response.getOutputStream();
		response.reset();
		SimpleDateFormat sdf = new SimpleDateFormat("yyyMMddHHmmss");
		String fileName = sdf.format(new Date());//这里是系统时间
		response.setHeader("Content-disposition", "attachment; filename="+java.net.URLEncoder.encode("文件名称", "UTF-8")+".xls");//这里添加文件名称
		response.setContentType("application/mesexcel");
		workbook.write(output);
		output.flush();
		IOUtils.closeQuietly(output);
	}