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我正在使用 Tika 自动检测被推送到 DMS 的文档的内容类型。除了电子邮件之外，几乎所有东西都可以正常工作。

我必须区分标准邮件消息（mime => message/rfc822）和签名邮件消息（mime => multipart/signed），但所有电子邮件都被检测为 message/rfc822。

未正确检测到的签名邮件具有以下内容类型标头：

Content-Type: multipart/signed; protocol="application/x-pkcs7-signature"; micalg=sha1; boundary="----4898E6D8BDE1929CA602BE94D115EF4C"

我用于解析的java代码是：

Detector detector;
List<Detector> detectors = new ArrayList<Detector>();
detectors.add(new ZipContainerDetector());
detectors.add(new POIFSContainerDetector());
detectors.add(MimeTypes.getDefaultMimeTypes());
detector = new CompositeDetector(detectors);
String mimetype = detector.detect(TikaInputStream.get(new File(args[0])), new Metadata()).toString();

我正在引用核心库和 tika-parsers 来检测 pdf 和 msword 文档。我还缺少其他东西吗？

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1 回答 1

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我解决了我的问题。我通过实现Detector接口实现了一个自定义检测器：

public class MultipartSignedDetector implements Detector {

  @Override
  public MediaType detect(InputStream is, Metadata metadata) throws IOException {

    TemporaryResources tmp = new TemporaryResources();

    TikaInputStream tis = TikaInputStream.get(is, tmp);
    tis.mark(Integer.MAX_VALUE);

    try {

      MimeMessage mimeMessage = null;
      String host = "host.com";
      Properties properties = System.getProperties();
      properties.setProperty("mail.smtp.host", host);
      Session session = Session.getDefaultInstance(properties);

      mimeMessage = new MimeMessage(session, tis);

      if(mimeMessage.getContentType() != null && mimeMessage.getMessageID() != null && mimeMessage.getContentType().toLowerCase().contains("multipart/signed"))
        return new MediaType("multipart", "signed");
      else
        return MediaType.OCTET_STREAM;

    } catch(Exception e) {
      return MediaType.OCTET_STREAM;
    } finally {
      try {
        tis.reset();
        tmp.dispose();
      } catch (TikaException e) {
        // ignore
    }
  }
 }
}

然后将自定义检测器添加到默认检测器之前的复合检测器：

Detector detector;
List<Detector> detectors = new ArrayList<Detector>();
detectors.add(new ZipContainerDetector());
detectors.add(new POIFSContainerDetector());

detectors.add(new MultipartSignedDetector());

detectors.add(MimeTypes.getDefaultMimeTypes());
detector = new CompositeDetector(detectors);
String mimetype = detector.detect(TikaInputStream.get(new File(args[0])), new Metadata()).toString();
于 2014-12-17T17:17:53.187 回答