Package org.dspace.storage.bitstore

Class BitstreamStorageServiceImpl

java.lang.Object

org.dspace.storage.bitstore.BitstreamStorageServiceImpl

All Implemented Interfaces:

BitstreamStorageService, org.springframework.beans.factory.InitializingBean

public class BitstreamStorageServiceImpl
extends Object
implements BitstreamStorageService, org.springframework.beans.factory.InitializingBean

Stores, retrieves and deletes bitstreams.

Presently, asset stores are specified in dspace.cfg. Since Java does not offer a way of detecting free disk space, the asset store to use for new bitstreams is also specified in a configuration property. The drawbacks to this are that the administrators are responsible for monitoring available space in the asset stores, and DSpace (Tomcat) has to be restarted when the asset store for new ('incoming') bitstreams is changed.

Mods by David Little, UCSD Libraries 12/21/04 to allow the registration of files (bitstreams) into DSpace.

Cleanup integration with checker package by Nate Sarr 2006-01. N.B. The dependency on the checker package isn't ideal - a Listener pattern would be better but was considered overkill for the purposes of integrating the checker. It would be worth re-considering a Listener pattern if another package needs to be notified of BitstreamStorageManager actions.

Author:

Peter Breton, Robert Tansley, David Little, Nathan Sarr

Field Summary

Fields

Modifier and Type	Field	Description
protected BitstreamService	bitstreamService
protected ChecksumHistoryService	checksumHistoryService
protected String	REGISTERED_FLAG	This prefix string marks registered bitstreams in internal_id

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	BitstreamStorageServiceImpl()

Method Summary

Modifier and Type	Method	Description
void	afterPropertiesSet()
void	cleanup(boolean deleteDbRecords, boolean verbose)	Clean up the bitstream storage area.
Bitstream	clone(Context context, Bitstream bitstream)	Clone the given bitstream to a new bitstream with a new ID.
Map<String,Object>	computeChecksum(Context context, Bitstream bitstream)
int	getIncoming()
Long	getLastModified(Bitstream bitstream)	Gets the last modified timestamp of the the given bitstream's content, if known.
protected BitStoreService	getStore(int position)
Map<Integer,BitStoreService>	getStores()
protected boolean	isRecent(Long lastModified)	Return true if this file is too recent to be deleted, false otherwise.
boolean	isRegisteredBitstream(String internalId)	Does the internal_id column in the bitstream row indicate the bitstream is a registered file
void	migrate(Context context, Integer assetstoreSource, Integer assetstoreDestination, boolean deleteOld, Integer batchCommitSize)	Migrates all assets off of one assetstore to another
void	printStores(Context context)	Print out (log/out) a listing of the assetstores configured, and how many assets they contain
UUID	register(Context context, Bitstream bitstream, int assetstore, String bitstreamPath)	Register a bitstream already in storage.
InputStream	retrieve(Context context, Bitstream bitstream)	Retrieve the bits for the bitstream with ID.
void	setIncoming(int incoming)
void	setStores(Map<Integer,BitStoreService> stores)
UUID	store(Context context, Bitstream bitstream, InputStream is)	Store a stream of bits.

Methods inherited from class java.lang.Object

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

Field Detail

bitstreamService

@Autowired(required=true)
protected BitstreamService bitstreamService

checksumHistoryService

@Autowired(required=true)
protected ChecksumHistoryService checksumHistoryService

REGISTERED_FLAG

protected final String REGISTERED_FLAG

This prefix string marks registered bitstreams in internal_id

See Also:

Constant Field Values

Constructor Detail

BitstreamStorageServiceImpl

protected BitstreamStorageServiceImpl()

Method Detail

afterPropertiesSet

public void afterPropertiesSet()
                        throws Exception

Specified by:

afterPropertiesSet in interface org.springframework.beans.factory.InitializingBean

Throws:

Exception

store

public UUID store(Context context,
                  Bitstream bitstream,
                  InputStream is)
           throws SQLException,
                  IOException

Description copied from interface: BitstreamStorageService

Store a stream of bits.

If this method returns successfully, the bits have been stored, and RDBMS metadata entries are in place (the context still needs to be completed to finalize the transaction).

If this method returns successfully and the context is aborted, then the bits will be stored in the asset store and the RDBMS metadata entries will exist, but with the deleted flag set.

If this method throws an exception, then any of the following may be true:

• Neither bits nor RDBMS metadata entries have been stored.
• RDBMS metadata entries with the deleted flag set have been stored, but no bits.
• RDBMS metadata entries with the deleted flag set have been stored, and some or all of the bits have also been stored.

Specified by:

store in interface BitstreamStorageService

Parameters:

context - The current context

bitstream - The bitstream to store

is - The stream of bits to store

Returns:

The ID of the stored bitstream

Throws:

SQLException - If a problem occurs accessing the RDBMS

IOException - If a problem occurs while storing the bits

register

public UUID register(Context context,
                     Bitstream bitstream,
                     int assetstore,
                     String bitstreamPath)
              throws SQLException,
                     IOException,
                     AuthorizeException

Register a bitstream already in storage.

Specified by:

register in interface BitstreamStorageService

Parameters:

context - The current context

assetstore - The assetstore number for the bitstream to be registered

bitstreamPath - The relative path of the bitstream to be registered. The path is relative to the path of ths assetstore.

bitstream - The bitstream to register

Returns:

The ID of the registered bitstream

Throws:

SQLException - If a problem occurs accessing the RDBMS

IOException - if IO error

AuthorizeException - Exception indicating the current user of the context does not have permission to perform a particular action.

computeChecksum

public Map<String,Object> computeChecksum(Context context,
                                                Bitstream bitstream)
                                         throws IOException

Specified by:

computeChecksum in interface BitstreamStorageService

Throws:

IOException

isRegisteredBitstream

public boolean isRegisteredBitstream(String internalId)

Description copied from interface: BitstreamStorageService

Does the internal_id column in the bitstream row indicate the bitstream is a registered file

Specified by:

isRegisteredBitstream in interface BitstreamStorageService

Parameters:

internalId - the value of the internal_id column

Returns:

true if the bitstream is a registered file

retrieve

public InputStream retrieve(Context context,
                            Bitstream bitstream)
                     throws SQLException,
                            IOException

Description copied from interface: BitstreamStorageService

Retrieve the bits for the bitstream with ID. If the bitstream does not exist, or is marked deleted, returns null.

Specified by:

retrieve in interface BitstreamStorageService

Parameters:

context - The current context

bitstream - The bitstream to retrieve

Returns:

The stream of bits, or null

Throws:

SQLException - If a problem occurs accessing the RDBMS

IOException - If a problem occurs while retrieving the bits

cleanup

public void cleanup(boolean deleteDbRecords,
                    boolean verbose)
             throws SQLException,
                    IOException,
                    AuthorizeException

Description copied from interface: BitstreamStorageService

Clean up the bitstream storage area. This method deletes any bitstreams which are more than 1 hour old and marked deleted. The deletions cannot be undone.

Specified by:

cleanup in interface BitstreamStorageService

Parameters:

deleteDbRecords - if true deletes the database records otherwise it only deletes the files and directories in the assetstore

verbose - verbosity flag

Throws:

SQLException - If a problem occurs accessing the RDBMS

IOException - If a problem occurs while cleaning up

AuthorizeException - Exception indicating the current user of the context does not have permission to perform a particular action.

getLastModified

@Nullable
public Long getLastModified(Bitstream bitstream)
                     throws IOException

Description copied from interface: BitstreamStorageService

Gets the last modified timestamp of the the given bitstream's content, if known.

Specified by:

getLastModified in interface BitstreamStorageService

Parameters:

bitstream - the bitstream.

Returns:

the timestamp in milliseconds, or null if unknown.

Throws:

IOException - if an unexpected io error occurs.

clone

public Bitstream clone(Context context,
                       Bitstream bitstream)
                throws SQLException,
                       IOException,
                       AuthorizeException

Description copied from interface: BitstreamStorageService

Clone the given bitstream to a new bitstream with a new ID. Metadata of the given bitstream are also copied to the new bitstream.

Specified by:

clone in interface BitstreamStorageService

Parameters:

context - The relevant DSpace Context.

bitstream - the bitstream to be cloned

Returns:

id of the clone bitstream. A general class of exceptions produced by failed or interrupted I/O operations.

Throws:

SQLException - An exception that provides information on a database access error or other errors.

AuthorizeException - Exception indicating the current user of the context does not have permission to perform a particular action.

IOException - if IO error

migrate

public void migrate(Context context,
                    Integer assetstoreSource,
                    Integer assetstoreDestination,
                    boolean deleteOld,
                    Integer batchCommitSize)
             throws IOException,
                    SQLException,
                    AuthorizeException

Migrates all assets off of one assetstore to another

Specified by:

migrate in interface BitstreamStorageService

Parameters:

assetstoreSource - source assetstore

assetstoreDestination - destination assetstore

context - The relevant DSpace Context.

deleteOld - whether to delete files from the source assetstore after migration

batchCommitSize - batch size

Throws:

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

SQLException - An exception that provides information on a database access error or other errors.

AuthorizeException - Exception indicating the current user of the context does not have permission to perform a particular action.

printStores

public void printStores(Context context)

Description copied from interface: BitstreamStorageService

Print out (log/out) a listing of the assetstores configured, and how many assets they contain

Specified by:

printStores in interface BitstreamStorageService

Parameters:

context - The relevant DSpace Context.

getIncoming

public int getIncoming()

setIncoming

public void setIncoming(int incoming)

setStores

public void setStores(Map<Integer,BitStoreService> stores)

getStores

public Map<Integer,BitStoreService> getStores()

isRecent

protected boolean isRecent(Long lastModified)

Return true if this file is too recent to be deleted, false otherwise.

Parameters:

lastModified - The time asset was last modified

Returns:

True if this file is too recent to be deleted

getStore

protected BitStoreService getStore(int position)
                            throws IOException

Throws:

IOException