上传excel文件，解析excel文件

需要jxl.jar包
上传excel文件：

//导入包
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;


//实现方法
StringBuilder sb = new StringBuilder();
    	String tempPath = request.getSession().getServletContext().getRealPath("/");
        try {
            DiskFileItemFactory factory = new DiskFileItemFactory();
            // 最大缓存
            factory.setSizeThreshold(5 * 1024);
            // 设置临时文件目录
            factory.setRepository(new File(tempPath));
            ServletFileUpload upload = new ServletFileUpload(factory);
            List items = upload.parseRequest(request);
            for (FileItem item : items) {
                if (!item.isFormField()) {
                	Calendar CD = Calendar.getInstance();
                    StringBuffer path = new StringBuffer();
                    path.append(request.getSession().getServletContext().getRealPath("/f")).append("/");
                    path.append("upload/"+System.currentTimeMillis() + CD.get(Calendar.MILLISECOND)).append(".").append(getFileExt(item.getName()));
                    // 写入文件
                    File file = new File(path.toString());
                    if (!file.getParentFile().exists()) {
                        file.getParentFile().mkdirs();
                    }
                    try {
                        item.write(file);
                    } catch (Exception e1) {
                        // TODO Auto-generated catch block
                        e1.printStackTrace();
                    }

                    List list = ExcelReaderUtil.readExcel(new File(path.toString()), 2);
                    Map map = ExcelReaderUtil.checkImport(list);
                    System.out.println(map);

                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        } 

//获取文件后缀名
public static String getFileExt(String f) {
        int i = f.lastIndexOf(".");
        if (i != -1) {
            return f.substring(i + 1).toLowerCase();
        }
        return "";
    }

/**
	 * @param excelFile 读取文件对象
	 * @param rowNum 从第几行开始读，如果有一行表头则从第二行开始读
	 * @return
	 * @throws BiffException
	 * @throws IOException
	 */
	public static List readExcel(File excelFile,int rowNum) throws BiffException,
			IOException {
		// 创建一个list 用来存储读取的内容
		List list = new ArrayList();
		Workbook rwb = null;
		Cell cell = null;
		// 创建输入流
		InputStream stream = new FileInputStream(excelFile);
		// 获取Excel文件对象
		rwb = Workbook.getWorkbook(stream);
		// 获取文件的指定工作表 默认的第一个
		Sheet sheet = rwb.getSheet(0);
		// 行数(表头的目录不需要，从1开始)
		for (int i = rowNum-1; i < sheet.getRows(); i++) {
			// 创建一个数组 用来存储每一列的值
			String[] str = new String[sheet.getColumns()];
			String temp = "";
			// 列数
			for (int j = 0; j < sheet.getColumns(); j++) {
				// 获取第i行，第j列的值
				cell = sheet.getCell(j, i);
				str[j] =replaceBlank(cell.getContents());
				temp = temp.concat(str[j]);
			}
			if(!StringUtils.isEmpty(temp)){
				// 把刚获取的列存入list
				list.add(str);
			}

		}
		// 返回值集合
		return list;
	}

    //功能描述： 去空格，回车符
    public static String replaceBlank(String str) {
        String dest = "";
        if (str!=null&&!str.equals("")) {
            Pattern p = Pattern.compile("\\s*|\t|\r|\n");
            Matcher m = p.matcher(str);
            dest = m.replaceAll("");
        }
        return dest.trim();
    }

    //制定导入实体类规则
     public static Map checkImport(List list_s){
    	Map map = new HashMap();
    	CountryObj countryObj = null;
    	String msg = "";
    	List countryList = new ArrayList();
    	if(list_s!=null&&list_s.size()>0){
    		for (int i = 0; i < list_s.size(); i++) {
    			String[] arr = list_s.get(i);
    			String country = arr[1];
    			countryObj = new CountryObj();
    			countryObj.setName(country);
    			countryObj.setTitle(country);
    			countryObj.setCreateAt(new Date());
    			countryObj.setUpdateAt(countryObj.getCreateAt());
    			countryObj.setUpdateBy(countryObj.getCreateBy());
    			countryList.add(countryObj);
    		}
    	}else{
    		msg = "上传失败，您选择的EXCEL文件为空。";
    	}
    	map.put("countryList", countryList);
    	map.put("msg", msg);
    	return map;
    }