Package org.apache.tika.digest

Class InputStreamDigester

java.lang.Object

org.apache.tika.digest.InputStreamDigester

All Implemented Interfaces:

Digester

public class InputStreamDigester
extends Object
implements Digester

Digester that uses TikaInputStream.enableRewind() and TikaInputStream.rewind() to read the entire stream for digesting, then rewind for subsequent processing.

Constructor Summary

Constructors

Constructor	Description
InputStreamDigester(String algorithm, String metadataKey, Encoder encoder)

Method Summary

Modifier and Type	Method	Description
void	digest(TikaInputStream tis, Metadata metadata, ParseContext parseContext)	Digests the TikaInputStream and stores the result in metadata.
protected Provider	getProvider()	When subclassing this, becare to ensure that your provider is thread-safe (not likely) or return a new provider with each call.

Methods inherited from class java.lang.Object

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

Constructor Details

InputStreamDigester

public InputStreamDigester(String algorithm,
 String metadataKey,
 Encoder encoder)

Parameters:

algorithm - name of the digest algorithm to retrieve from the Provider

metadataKey - the full metadata key to use when storing the digest (e.g., "X-TIKA:digest:MD5" or "X-TIKA:digest:SHA256:BASE32")

encoder - encoder to convert the byte array returned from the digester to a string

Method Details

getProvider

protected Provider getProvider()

When subclassing this, becare to ensure that your provider is thread-safe (not likely) or return a new provider with each call.

Returns:

provider to use to get the MessageDigest from the algorithm name. Default is to return null.

digest

public void digest(TikaInputStream tis,
 Metadata metadata,
 ParseContext parseContext)
            throws IOException

Digests the TikaInputStream and stores the result in metadata.

Uses TikaInputStream.enableRewind() to ensure the stream can be rewound after digesting, then calls TikaInputStream.rewind() to reset the stream for subsequent processing.

Specified by:

digest in interface Digester

Parameters:

tis - TikaInputStream to digest

metadata - metadata in which to store the digest information

parseContext - ParseContext -- not actually used yet, but there for future expansion

Throws:

IOException - on IO problem or IllegalArgumentException if algorithm couldn't be found