Package org.apache.tika.detect.zip

Class DefaultZipContainerDetector

java.lang.Object

org.apache.tika.detect.zip.DefaultZipContainerDetector

All Implemented Interfaces:

Serializable, SelfConfiguring, Detector

Direct Known Subclasses:

StreamingZipContainerDetector

public class DefaultZipContainerDetector
extends Object
implements Detector

This class is designed to detect subtypes of zip-based file formats. For the sake of efficiency, it also detects archive and compressor formats via commons-compress.

As a first step, it uses commons-compress to detect any archive format supported by commons-compress. If "zip" file is detected, then the ZipContainerDetectors are run to try to identify a subtype.

If an archive format that is not a zip is detected, that mime type is returned.

Finally, if the file is not detected as an archive format, this runs commons-compress' compressor format detector.

For TikaInputStream, file-based detection is used (TikaInputStream handles spilling to disk automatically if needed).

ZIP Salvaging

When a ZIP file cannot be opened directly (truncated or corrupted), and ParsingIntent.WILL_PARSE is present in the ParseContext, this detector will attempt to salvage the file using ZipSalvager. Salvaging reconstructs a valid ZIP structure from the local file headers.

When salvaging succeeds, Zip.SALVAGED is set to true in the metadata, and the salvaged ZipFile is stored in TikaInputStream.getOpenContainer() for reuse by parsers.

Note: If you use parsers directly without this detector (or without AutoDetectParser), salvaging will not occur and truncated files may fail to parse.

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected List<ZipContainerDetector>	staticZipDetectors

Constructor Summary

Constructors

Constructor	Description
DefaultZipContainerDetector()
DefaultZipContainerDetector(List<ZipContainerDetector> zipDetectors)
DefaultZipContainerDetector(ServiceLoader loader)

Method Summary

Modifier and Type	Method	Description
MediaType	detect(TikaInputStream tis, Metadata metadata, ParseContext parseContext)	Detects the content type of the given input document.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

staticZipDetectors

protected List<ZipContainerDetector> staticZipDetectors

Constructor Details

DefaultZipContainerDetector

public DefaultZipContainerDetector()

DefaultZipContainerDetector

public DefaultZipContainerDetector(ServiceLoader loader)

DefaultZipContainerDetector

public DefaultZipContainerDetector(List<ZipContainerDetector> zipDetectors)

Method Details

detect

public MediaType detect(TikaInputStream tis,
 Metadata metadata,
 ParseContext parseContext)
                 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 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:

tis - document input stream, or null

metadata - input metadata for the document

parseContext - the parse context

Returns:

detected media type, or application/octet-stream

Throws:

IOException - if the document input stream could not be read