Package org.dspace.storage.bitstore

Interface BitStoreService

All Known Implementing Classes:

BaseBitStoreService, DSBitStoreService, S3BitStoreService

public interface BitStoreService

A low-level asset store interface

Author:

Richard Rodgers, Peter Dietz

Method Summary

Modifier and Type	Method	Description
Map<String,Object>	about(Bitstream bitstream, List<String> attrs)	Obtain technical metadata about an asset in the asset store.
String	generateId()	Return an identifier unique to this asset store instance
InputStream	get(Bitstream bitstream)	Retrieve the bits for bitstream
void	init()	Initialize the asset store
default boolean	isEnabled()	Determines if a store is enabled, by default is enabled
boolean	isInitialized()	Determines if a store has been initialized
void	put(Bitstream bitstream, InputStream inputStream)	Store a stream of bits.
void	remove(Bitstream bitstream)	Remove an asset from the asset store.

Method Detail

init

void init()
   throws IOException

Initialize the asset store

Throws:

IOException - A general class of exceptions produced by failed or interrupted I/O operations.

generateId

String generateId()

Return an identifier unique to this asset store instance

Returns:

a unique ID

get

InputStream get(Bitstream bitstream)
         throws IOException

Retrieve the bits for bitstream

Parameters:

bitstream - DSpace Bitstream object

Returns:

The stream of bits

Throws:

IOException - If a problem occurs while retrieving the bits, or if no asset with ID exists in the store

put

void put(Bitstream bitstream,
         InputStream inputStream)
  throws IOException

Store a stream of bits.

If this method returns successfully, the bits have been stored. If an exception is thrown, the bits have not been stored.

Parameters:

bitstream - The bitstream object

inputStream - The stream of bits

Throws:

IOException - If a problem occurs while storing the bits

about

Map<String,Object> about(Bitstream bitstream,
                               List<String> attrs)
                        throws IOException

Obtain technical metadata about an asset in the asset store.

Parameters:

bitstream - The bitstream to describe

attrs - A List of desired metadata fields

Returns:

attrs A Map with key/value pairs of desired metadata If file not found, then return null

Throws:

IOException - If a problem occurs while obtaining metadata

remove

void remove(Bitstream bitstream)
     throws IOException

Remove an asset from the asset store.

Parameters:

bitstream - The bitstream of the asset to delete

Throws:

IOException - If a problem occurs while removing the asset

isInitialized

boolean isInitialized()

Determines if a store has been initialized

Returns:

boolean true if initialized, false otherwise

isEnabled

default boolean isEnabled()

Determines if a store is enabled, by default is enabled

Returns:

boolean true if enabled, false otherwise