org.egothor.repository
Interface DataRepository

All Known Implementing Classes:

Berkeley, BlobRepository, DocumentsDB, WebStore

public interface DataRepository

Interface of the data blocks repository.

Author:

Leo

Nested Class Summary

static interface

DataRepository.TupleSequence

Method Summary

int	addItem(long key, byte[] document, int length) Adds another document into the repository.
void	close() Closes the repository.
void	destroy() Destroy the repository.
DataInputStream	elementAt(long key, int revision) Retrieves a data block.
DataRepository.TupleSequence	elements() The tuples are [long:uid;int:rev;Object:DataInputStream].
void	flush()

Method Detail

addItem

int addItem(long key,
            byte[] document,
            int length)

Adds another document into the repository. If the implementation is able to recognize whether the incoming data block is still the same (as the existing in the repository), it would discard the insertion request and return 0 as the signal of no-op.

Returns:

revision number (0 iff unchanged) or -1 when fails

elementAt

DataInputStream elementAt(long key,
                          int revision)

Retrieves a data block.

Parameters:

key - the key of the block

revision - revision number of the block, 0 is used for the latest (current) revision

Returns:

null if the revision is not available (or the key is unknown)

elements

DataRepository.TupleSequence elements()

The tuples are [long:uid;int:rev;Object:DataInputStream].

flush

void flush()

close

void close()

Closes the repository.

destroy

void destroy()

Destroy the repository.