Java使用poi读取Excel文件例子

需要导入的包和 该例子读取的excel文件 在下面上传了，需要请下载：
package excel;


import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.LinkedList;
import java.util.List;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFDateUtil;
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.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
/**
 * 读取excel文件
 * @author Jiacheng
 *Poi解析2003时使用的是HSSFCell，而2007的则是 
	XSSFCell，是完全不同的两套API
	必须先要判断excel的类型，不过 HSSFWorkbook 和 XSSFWorkbook 实现的接口都是一样的Workbook，直接在实例化接口的时候有点区别其他时候没有任何差异。
 */
public class ReadExcelUtil {
	public static List<List<Object>> readExcel(File file) throws IOException {
		String fileName = file.getName();
		String extension = fileName.lastIndexOf(".") == -1 ? "" : fileName
				.substring(fileName.lastIndexOf(".") + 1);
		if ("xls".equals(extension)) {
			return read2003Excel(file);
		} else if ("xlsx".equals(extension)) {
			return read2007Excel(file);
		} else {
			throw new IOException("不支持的文件类型");
		}
	}

	/**
	 * 读取 office 2003 excel
	 * 
	 * @throws IOException
	 * @throws FileNotFoundException
	 */
	private static List<List<Object>> read2003Excel(File file)
			throws IOException {
		List<List<Object>> list = new LinkedList<List<Object>>();
		HSSFWorkbook hwb = new HSSFWorkbook(new FileInputStream(file));
		HSSFSheet sheet = hwb.getSheetAt(0);
		Object value = null;
		HSSFRow row = null;
		HSSFCell cell = null;
		int counter = 0;
		for (int i = sheet.getFirstRowNum(); counter < sheet
				.getPhysicalNumberOfRows(); i++) {
//			if(i==0){
//				//跳过第一行
//				continue;
//			}
			row = sheet.getRow(i);
			List<Object> linked = new LinkedList<Object>();
			for (int j = row.getFirstCellNum(); j <= row.getLastCellNum(); j++) {
				cell = row.getCell(j);
				if (cell == null) {
					value="无";//导入不能为空
					linked.add(value);
					//System.out.println(value);
					continue;
				}
				DecimalFormat df = new DecimalFormat("0");// 格式化 number String
															// 字符
				SimpleDateFormat sdf = new SimpleDateFormat(
						"yyyy-MM-dd");// 格式化日期字符串
				DecimalFormat nf = new DecimalFormat("0");// 格式化数字
				switch (cell.getCellType()) {
				case XSSFCell.CELL_TYPE_STRING:
					value = cell.getStringCellValue();
					//System.out.println(i + "行" + j + " 列 is String type" +"  "+value);
					break;
				case XSSFCell.CELL_TYPE_NUMERIC:
//					System.out.println(i + "行" + j
//							+ " 列 is Number type ; DateFormt:"
//							+ cell.getCellStyle().getDataFormatString());
					if ("@".equals(cell.getCellStyle().getDataFormatString())) {
						value = df.format(cell.getNumericCellValue());
					} else if ("General".equals(cell.getCellStyle()
							.getDataFormatString())) {
						value = nf.format(cell.getNumericCellValue());
					} else {
						value = sdf.format(HSSFDateUtil.getJavaDate(cell
								.getNumericCellValue()));
					}
					break;
				case XSSFCell.CELL_TYPE_BOOLEAN:
					value = cell.getBooleanCellValue();
					break;
				case XSSFCell.CELL_TYPE_BLANK:
					value = "";
					break;
				default:
					value = cell.toString();
				}
				if (value == null || "".equals(value)) {
					value="无";//导入不能为空
				}
				//System.out.println(value);
				linked.add(value);
			}
			list.add(linked);
		}
		return list;
	}

	/**
	 * 读取Office 2007 excel
	 * */
	private static List<List<Object>> read2007Excel(File file)
			throws IOException {
		List<List<Object>> list = new LinkedList<List<Object>>();
		// 构造 XSSFWorkbook 对象，strPath 传入文件路径
		XSSFWorkbook xwb = new XSSFWorkbook(new FileInputStream(file));
		// 读取第一章表格内容
		XSSFSheet sheet = xwb.getSheetAt(0);
		Object value = null;
		XSSFRow row = null;
		XSSFCell cell = null;
		int counter = 0;
		for (int i = sheet.getFirstRowNum(); counter < sheet
				.getPhysicalNumberOfRows(); i++) {
			if(i==0){
				//跳过第一行
				continue;
			}
			row = sheet.getRow(i);
			if (row == null) {
			     break;
			}
			List<Object> linked = new LinkedList<Object>();
			for (int j = row.getFirstCellNum(); j <row.getLastCellNum(); j++) {
				cell = row.getCell(j);
				if (cell == null) {
					value="无";//导入不能为空
					linked.add(value);
					//System.out.println(value);
					continue;
				}
				//System.out.println(value);
				DecimalFormat df = new DecimalFormat("0");// 格式化 number String
															// 字符
				SimpleDateFormat sdf = new SimpleDateFormat(
						"yyyy-MM-dd");// 格式化日期字符串
				DecimalFormat nf = new DecimalFormat("0");// 格式化数字
				switch (cell.getCellType()) {
						case XSSFCell.CELL_TYPE_STRING:
							//System.out.println(i + "行" + j + " 列 is String type");
							value = cell.getStringCellValue();
							break;
						case XSSFCell.CELL_TYPE_NUMERIC:
						//	System.out.println(i + "行" + j
								//	+ " 列 is Number type ; DateFormt:"
								//	+ cell.getCellStyle().getDataFormatString());
							if ("@".equals(cell.getCellStyle().getDataFormatString())) {
								value = df.format(cell.getNumericCellValue());
							} else if ("General".equals(cell.getCellStyle()
									.getDataFormatString())) {
								value = nf.format(cell.getNumericCellValue());
							} else {
								value = sdf.format(HSSFDateUtil.getJavaDate(cell
										.getNumericCellValue()));
							}
							break;
						case XSSFCell.CELL_TYPE_BOOLEAN:
							value = cell.getBooleanCellValue();
							break;
						case XSSFCell.CELL_TYPE_BLANK://空格，空白
							value = "";
							break;
						default:
							value = cell.toString();
				}
				if (value == null || "".equals(value)) {
					value="无";//导入不能为空
				}
				//System.out.println(value);
				linked.add(value);
			}
			list.add(linked);
		}
		return list;
	}

	public static void main(String[] args) {
		try {
			int count=0;
			long time1=System.currentTimeMillis();
			List<List<Object>> list=readExcel(new File("D:\\test.xlsx"));
			System.out.println("读取花费时间："+(System.currentTimeMillis()-time1)/1000.0);
			
			for(List<Object> list2 :list){
				count++;
				for(int i=0;i<list2.size();i++){
					System.out.print(list2.get(i)+"  ");
				}
				System.out.println("第"+count+"组");
			}
			System.out.println("ok!");
			// readExcel(new File("D:\\test.xls"));
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}