Class MagicDetector

  • All Implemented Interfaces:
    Serializable, Detector

    public class MagicDetector
    extends Object
    implements Detector
    Content type detection based on magic bytes, i.e. type-specific patterns near the beginning of the document input stream.

    Because this works on bytes, not characters, by default any string matching is done as ISO_8859_1. To use an explicit different encoding, supply a type other than "string" / "stringignorecase"

    Since:
    Apache Tika 0.3
    See Also:
    Serialized Form
    • Constructor Detail

      • MagicDetector

        public MagicDetector​(MediaType type,
                             byte[] pattern)
        Creates a detector for input documents that have the exact given byte pattern at the beginning of the document stream.
        Parameters:
        type - matching media type
        pattern - magic match pattern
      • MagicDetector

        public MagicDetector​(MediaType type,
                             byte[] pattern,
                             int offset)
        Creates a detector for input documents that have the exact given byte pattern at the given offset of the document stream.
        Parameters:
        type - matching media type
        pattern - magic match pattern
        offset - offset of the pattern match
      • MagicDetector

        public MagicDetector​(MediaType type,
                             byte[] pattern,
                             byte[] mask,
                             int offsetRangeBegin,
                             int offsetRangeEnd)
        Creates a detector for input documents that meet the specified magic match. pattern must NOT be a regular expression. Constructor maintained for legacy reasons.
      • MagicDetector

        public MagicDetector​(MediaType type,
                             byte[] pattern,
                             byte[] mask,
                             boolean isRegex,
                             int offsetRangeBegin,
                             int offsetRangeEnd)
        Creates a detector for input documents that meet the specified magic match.
      • MagicDetector

        public MagicDetector​(MediaType type,
                             byte[] pattern,
                             byte[] mask,
                             boolean isRegex,
                             boolean isStringIgnoreCase,
                             int offsetRangeBegin,
                             int offsetRangeEnd)
        Creates a detector for input documents that meet the specified magic match.
    • Method Detail

      • detect

        public MediaType detect​(InputStream input,
                                Metadata metadata)
                         throws IOException
        Description copied from interface: Detector
        Detects the content type of the given input document. Returns application/octet-stream if the type of the document can not be detected.

        If the document input stream is not available, then the first argument may be null. Otherwise the detector may read bytes from the start of the stream to help in type detection. The given stream is guaranteed to support the mark feature and the detector is expected to mark the stream before reading any bytes from it, and to reset the stream before returning. The stream must not be closed by the detector.

        The given input metadata is only read, not modified, by the detector.

        Specified by:
        detect in interface Detector
        Parameters:
        input - document input stream, or null
        metadata - ignored
        Returns:
        detected media type, or application/octet-stream
        Throws:
        IOException - if the document input stream could not be read
      • getLength

        public int getLength()
      • toString

        public String toString()
        Returns a string representation of the Detection Rule. Should sort nicely by type and details, as we sometimes compare these.
        Overrides:
        toString in class Object