org.dspace.storage.bitstore

Class DSBitStoreService

java.lang.Object

org.dspace.storage.bitstore.DSBitStoreService

All Implemented Interfaces:

BitStoreService

public class DSBitStoreService
extends Object
implements BitStoreService

Native DSpace (or "Directory Scatter" if you prefer) asset store. Implements a directory 'scatter' algorithm to avoid OS limits on files per directory.

Author:

Peter Breton, Robert Tansley, Richard Rodgers, Peter Dietz

Field Summary

Fields

Modifier and Type	Field and Description
protected String	REGISTERED_FLAG

Constructor Summary

Constructors

Constructor and Description
DSBitStoreService()

Method Summary

Modifier and Type	Method and Description
Map	about(Bitstream bitstream, Map 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 the asset with ID.
File	getBaseDir()
protected File	getFile(Bitstream bitstream) Return the file corresponding to a bitstream.
protected String	getIntermediatePath(String iInternalId) Return the intermediate path derived from the internal_id.
void	init() Initialize the asset store
boolean	isRegisteredBitstream(String internalId)
void	put(Bitstream bitstream, InputStream in) Store a stream of bits.
void	remove(Bitstream bitstream) Remove an asset from the asset store.
void	setBaseDir(File baseDir)

Methods inherited from class java.lang.Object

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

Field Detail

REGISTERED_FLAG

protected final String REGISTERED_FLAG

See Also:

Constant Field Values

Constructor Detail

DSBitStoreService

public DSBitStoreService()

Method Detail

init

public void init()

Initialize the asset store

Specified by:

init in interface BitStoreService

generateId

public String generateId()

Return an identifier unique to this asset store instance

Specified by:

generateId in interface BitStoreService

Returns:

a unique ID

get

public InputStream get(Bitstream bitstream)
                throws IOException

Retrieve the bits for the asset with ID. If the asset does not exist, returns null.

Specified by:

get in interface BitStoreService

Parameters:

bitstream - The ID of the asset to retrieve

Returns:

The stream of bits, or null

Throws:

IOException - If a problem occurs while retrieving the bits

put

public void put(Bitstream bitstream,
                InputStream in)
         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.

Specified by:

put in interface BitStoreService

Parameters:

in - The stream of bits to store

bitstream - The bitstream object

Throws:

IOException - If a problem occurs while storing the bits

about

public Map about(Bitstream bitstream,
                 Map attrs)
          throws IOException

Obtain technical metadata about an asset in the asset store.

Specified by:

about in interface BitStoreService

Parameters:

bitstream - The asset to describe

attrs - A Map whose keys consist of desired metadata fields

Returns:

attrs A Map with key/value pairs of desired metadata

Throws:

IOException - If a problem occurs while obtaining metadata

remove

public void remove(Bitstream bitstream)
            throws IOException

Remove an asset from the asset store. An irreversible operation.

Specified by:

remove in interface BitStoreService

Parameters:

bitstream - The asset to delete

Throws:

IOException - If a problem occurs while removing the asset

getFile

protected File getFile(Bitstream bitstream)
                throws IOException

Return the file corresponding to a bitstream. It's safe to pass in null.

Parameters:

bitstream - the database table row for the bitstream. Can be null

Returns:

The corresponding file in the file system, or null

Throws:

IOException - If a problem occurs while determining the file

getIntermediatePath

protected String getIntermediatePath(String iInternalId)

Return the intermediate path derived from the internal_id. This method splits the id into groups which become subdirectories.

Parameters:

iInternalId - The internal_id

Returns:

The path based on the id without leading or trailing separators

isRegisteredBitstream

public boolean isRegisteredBitstream(String internalId)

getBaseDir

public File getBaseDir()

setBaseDir

public void setBaseDir(File baseDir)