Package dk.netarkivet.archive.checksum

Class DatabaseChecksumArchive

java.lang.Object

dk.netarkivet.archive.checksum.DatabaseChecksumArchive

All Implemented Interfaces:

ChecksumArchive

public class DatabaseChecksumArchive
extends Object
implements ChecksumArchive

A ChecksumArchive persisted with a Berkeley DB JE Database. Migrating from the FileChecksumArchive to the DatabaseChecksumArchive is done with the LoadDatabaseChecksumArchive tool.

Constructor Summary

Constructors

Constructor	Description
DatabaseChecksumArchive()	Constructor.

Method Summary

Modifier and Type	Method	Description
String	calculateChecksum(File f)	Method for calculating the checksum of a specific file.
String	calculateChecksum(InputStream is)	Method for calculating the checksum when the file is received in the form of an inputstream.
void	cleanup()	Method for cleaning up when closing down.
File	correct(String filename, File correctFile)	Method for removing a bad entry from the archive.
File	getAllFilenames()	Method for retrieving the names of all the files within the archive as a temporary file.
File	getArchiveAsFile()	Method for retrieving the archive as a temporary file containing the checksum entries.
String	getChecksum(String filename)	Method for retrieving the checksum of a specific entry in the archive.
static DatabaseChecksumArchive	getInstance()	Method for obtaining the current singleton instance of this class.
boolean	hasEnoughSpace()	Method for checking whether there is enough space left on the hard drive.
boolean	hasEntry(String filename)	Method for checking whether an entry exists within the archive.
void	put(String filename, String checksum)	Update the database with a new filename and its checksum.
void	upload(RemoteFile file, String filename)	Method for uploading a new file to the archive.
void	upload(String checksum, String filename)	Upload a filename with a pre-computed checksum.

Methods inherited from class java.lang.Object

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

Constructor Detail

DatabaseChecksumArchive

public DatabaseChecksumArchive()
                        throws com.sleepycat.je.DatabaseException

Constructor. Retrieves the minimum space left variable, and ensures the existence of the archive file. If the file does not exist, then it is created.

Throws:

Exception

com.sleepycat.je.DatabaseException

Method Detail

getInstance

public static DatabaseChecksumArchive getInstance()
                                           throws Exception

Method for obtaining the current singleton instance of this class. If the instance of this class has not yet been constructed, then it will be initialised.

Returns:

The current instance of this class.

Throws:

Exception

hasEnoughSpace

public boolean hasEnoughSpace()

Description copied from interface: ChecksumArchive

Method for checking whether there is enough space left on the hard drive.

Specified by:

hasEnoughSpace in interface ChecksumArchive

Returns:

Whether there is enough space left on the hard drive.

correct

public File correct(String filename,
                    File correctFile)
             throws IOFailure,
                    ArgumentNotValid,
                    IllegalState

Description copied from interface: ChecksumArchive

Method for removing a bad entry from the archive. This finds the record and removes it if it has the incorrect checksum. The incorrect record is not deleted, but instead put into a backup file for all the incorrect records.

Specified by:

correct in interface ChecksumArchive

Parameters:

filename - The name of the file whose record should be removed.

correctFile - The correct remote file to replace the bad one in the archive.

Returns:

A file containing the removed data.

Throws:

IOFailure - If the entry cannot be corrected.

ArgumentNotValid - If one of the arguments are not valid.

IllegalState - If no such entry exists to be corrected, or if the entry has a different checksum than expected.

getChecksum

public String getChecksum(String filename)

Description copied from interface: ChecksumArchive

Method for retrieving the checksum of a specific entry in the archive.

Specified by:

getChecksum in interface ChecksumArchive

Parameters:

filename - The name of the file entry in the archive for whom the checksum should be retrieved.

Returns:

The checksum of a record, or null if it was not found.

hasEntry

public boolean hasEntry(String filename)

Description copied from interface: ChecksumArchive

Method for checking whether an entry exists within the archive.

Specified by:

hasEntry in interface ChecksumArchive

Parameters:

filename - The name of the file whose entry in the archive should be determined.

Returns:

Whether an entry with the filename was found.

upload

public void upload(RemoteFile file,
                   String filename)

Description copied from interface: ChecksumArchive

Method for uploading a new file to the archive. The checksum of the file needs to be calculated before it is placed in the archive with the given filename.

Specified by:

upload in interface ChecksumArchive

Parameters:

file - The remote file to be uploaded.

filename - The name of the file.

upload

public void upload(String checksum,
                   String filename)

Description copied from interface: ChecksumArchive

Upload a filename with a pre-computed checksum.

Specified by:

upload in interface ChecksumArchive

put

public void put(String filename,
                String checksum)

Update the database with a new filename and its checksum.

Parameters:

filename - A given filename

checksum - The related checksum

calculateChecksum

public String calculateChecksum(File f)

Description copied from interface: ChecksumArchive

Method for calculating the checksum of a specific file.

Specified by:

calculateChecksum in interface ChecksumArchive

Parameters:

f - The file to calculate the checksum from.

Returns:

The checksum of the file.

calculateChecksum

public String calculateChecksum(InputStream is)

Description copied from interface: ChecksumArchive

Method for calculating the checksum when the file is received in the form of an inputstream.

Specified by:

calculateChecksum in interface ChecksumArchive

Parameters:

is - The input stream to calculate the checksum from.

Returns:

The checksum of the inputstream.

getArchiveAsFile

public File getArchiveAsFile()

Description copied from interface: ChecksumArchive

Method for retrieving the archive as a temporary file containing the checksum entries.

Specified by:

getArchiveAsFile in interface ChecksumArchive

Returns:

A temporary checksum file.

getAllFilenames

public File getAllFilenames()

Description copied from interface: ChecksumArchive

Method for retrieving the names of all the files within the archive as a temporary file.

Specified by:

getAllFilenames in interface ChecksumArchive

Returns:

A temporary file containing the list of all the filenames. This file has one filename per line.

cleanup

public void cleanup()

Description copied from interface: ChecksumArchive

Method for cleaning up when closing down.

Specified by:

cleanup in interface ChecksumArchive