alluxio.underfs

Interface ContentHashable

All Known Implementing Classes:

AtomicFileOutputStream, COSOutputStream, GCSOutputStream, GCSV2OutputStream, HdfsUnderFileOutputStream, ObjectLowLevelOutputStream, OBSLowLevelOutputStream, OBSOutputStream, OSSLowLevelOutputStream, OSSOutputStream, S3ALowLevelOutputStream, S3AOutputStream

public interface ContentHashable

Interface for returning the content hash. Instances of OutputStream returned by UnderFileSystem.create(java.lang.String) may implement this interface if the UFS returns the hash of the content written when the stream is closed. The content hash will then be used as part of the metadata fingerprint when the file is completed on the Alluxio master.

Method Summary

Modifier and Type	Method and Description
Optional<String>	getContentHash()

Method Detail

getContentHash

Optional<String> getContentHash()
                         throws IOException

Returns:

the content hash of the file written to the UFS if available after the stream has been closed

Throws:

IOException