如何知道excel是否受密码保护

Question

如何检测excel（xls和xlsx）文件是否受密码保护？有没有要检查的旗帜？ 注意：有两种类型可以为excel（xls / xlsx）提供密码：

1. 密码保护（excel-＆gt;另存为＆gt;工具 - ＆gt;一般选项）
2. 加密密码（excel-＆gt;文件允许 - >加密）

我的代码仅适用于加密密码的xls。

1. xls encrypted-EncryptedDocumentException -pass（适当的例外）
2. xls password protected -IllegalArgumentException-fail（一般例外）
3. xlsx encrypted-POIXMLException-fail（一般例外）
4. xlsx密码保护-POIXMLException-fail（一般例外）

对于上述失败的情况而不是一般异常，我想改进此代码。

使用的罐子：

POI-3.5-FINAL-20090928.jar

POI-3.7-20101029.jar

poi-ooxml-3.7-20101029.jar

       public static String excelFileScanner(InputStream excelFileToScan, 
       String  uploadFileExt) throws IOException {
    String returnStatus = null;
    try {

        Workbook wb = null;// WorkbookFactory.create(excelFileToScan);
        if (uploadFileExt.equalsIgnoreCase("xlsx")) {
            wb = new XSSFWorkbook(excelFileToScan);
        } else {
            // POIFSFileSystem fs = new POIFSFileSystem(excelFileToScan);
            wb = new HSSFWorkbook(excelFileToScan);
        }

        int noOfSheet = wb.getNumberOfSheets();
        for (int i = 0; i < noOfSheet; i++) {
            Sheet sheet = wb.getSheetAt(i);

            for (Row row : sheet) {
                for (Cell cell : row) {
                    if (cell.getCellType() == Cell.CELL_TYPE_FORMULA) {
                        return "malicious";

                    }
                }
            }
        }
        returnStatus = "valid";
    } catch (POIXMLException ex1) {
        // catch (InvalidFormatException ex1) {
        returnStatus = ex1.getClass().getSimpleName();
        if (ex1 != null && ex1.getCause() != null) {

            System.out.println("reason: " + ex1.getCause().toString());

            System.out.println("passwordprotected");
        } else {
            System.out.println("else block: " + ex1);
        }

    } catch (EncryptedDocumentException ex2) {
        returnStatus = "passwordProtected";
    } catch (Exception ex) {
        returnStatus = ex.getMessage();

    }

    return returnStatus;
}

public static void main(String[] args) throws IOException {

    try {
        File folder = new File("/Desktop/Excel/");
        File[] listOfFiles = folder.listFiles();
        for (File file : listOfFiles) {
            if (file.isFile()) {
                System.out.println(file.getName());
                String uploadFileExt = null;
                String filename = file.getName();
                int extnSeparatorIndex = filename.lastIndexOf(".");
                if (extnSeparatorIndex != -1) {
                    if (extnSeparatorIndex != file.length() - 1) {
                        uploadFileExt = filename.substring(extnSeparatorIndex + 1);
                    }
                    // String uploadFileExt = file.getAbsolutePath();
                    InputStream fileUploaded = new FileInputStream(file.getAbsolutePath());
                    System.out.println("extension:  " + uploadFileExt);
                    String returnStatus= PasswordExcelRead.excelFileScanner(fileUploaded, uploadFileExt);
                    System.out.println("Final: " + returnStatus);


                }
            }
        }
    } catch (FileNotFoundException e) {

        e.printStackTrace();
    }
}

Answer 1

通常，您会捕获EncryptedDocumentException以检查文件是否受密码保护：

InputStream input = ...
Workbook wb;
try {
    wb = WorkbookFactory.create(input)
} catch (EncryptedDocumentException e) {
   // password protected
}