判断Excel文件在某目录是否存在及获取其文件内容

String path = request.getServletContext().getRealPath("/upload/Excel");
if (file.exists()){
    File[] files=file.listFiles();
    if (files.length==0){
        System.out.println("文件夹为空");
        return;
    }else {
        for(File file2:files){
            String filename=file2.getName();
            String newFileName = filename.substring(filename.lastIndexOf("."));
            if (newFileName.equals(".xls")){
                 filename=filename.substring(0,filename.lastIndexOf("."));
                if (filename.equals(excelname)){

                    try {
                        Workbook rwb=Workbook.getWorkbook(file2);
                        Sheet rs=rwb.getSheet(0);//或者rwb.getSheet(0)
                        int clos=rs.getColumns();//得到所有的列
                        int rows=rs.getRows();//得到所有的行

                        System.out.println(clos+" rows:"+rows);
                        for (int i = 0; i < rows; i++) {
                            Map<String,String> map=new HashMap<>();
                            for (int j = 0; j < clos; j++) {
                                map.put(j+"",rs.getCell(j,i).getContents());
                            }
                            mapList.add(map);
                        }
                    } catch (Exception e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
            }
        }
    }
}