com.sleepycat.je

Interface BackupFileCopy

All Known Implementing Classes:

BackupFSArchiveCopy

public interface BackupFileCopy

Method Summary

Modifier and Type	Method and Description
byte[]	checksum(URL archiveURL) Returns the checksum computed by reading archiveFile.
byte[]	copy(File localFile, URL archiveURL) Copies the file from the local machine into the archive.
String	getChecksumAlg() Returns the checksum algorithm used to checksum the archive file being accessed.
String	getCompressionAlg() Returns the compression algorithm used to compress the archive file being accessed.
String	getEncryptionAlg() Returns the encryption algorithm used to encrypt/decrypt the archive file being accessed.
void	initialize(File configFile) initialize is invoked exactly once after the creation of the object via its noargs constructor.

Method Detail

initialize

void initialize(File configFile)
         throws InterruptedException,
                IOException

initialize is invoked exactly once after the creation of the object via its noargs constructor.

Parameters:

configFile - the config file used to initialize the object. It could, for example, contain the credentials needed to access the archive,the compression and encryption algorithms used to store archive files, etc. The format of the config file (properties, json, etc.) is private to the implementation.

Throws:

InterruptedException - if the initialize operation is interrupted

IllegalArgumentException - if the configuration was invalid

IOException - if some irrecoverable I/O issue was encountered during initialization.

getEncryptionAlg

String getEncryptionAlg()

Returns the encryption algorithm used to encrypt/decrypt the archive file being accessed. The encryption algorithm is set via the config file during the call to initialize(java.io.File). The algorithm name is a valid argument to Cipher or the provider overloading used by the implementation.

Returns:

null (if no encryption is in use), or the name of the encryption algorithm.

getCompressionAlg

String getCompressionAlg()

Returns the compression algorithm used to compress the archive file being accessed. The compression algorithm is set via the config file during the call to initialize(java.io.File).

Returns:

null (if no compression is in use), or the name of the compression algorithm. The value (for now) could be one of zip or gzip.

getChecksumAlg

String getChecksumAlg()

Returns the checksum algorithm used to checksum the archive file being accessed. The checksum algorithm is set via the config file during the call to initialize(java.io.File). The algorithm name is a valid argument to MessageDigest.getInstance(String) or the provider overloading used by the implementation.

Returns:

The name of the checksum algorithm

copy

byte[] copy(File localFile,
            URL archiveURL)
     throws InterruptedException,
            IOException

Copies the file from the local machine into the archive. The file is encrypted and compressed in the archive according to the configuration specified by initialize(java.io.File). Note that localFile could be modified concurrently (for table row erasure) while the copy operation is in progress, so that the version of file that is copied is partially erased. Erasure modifications do not change the length of the file, just its existing contents. The restored environment is resilient to such pa partially erased state. The checksum returned for such a concurrently erased file thus reflects the contents of the file in the archive and will not match the state of the localFile. If archiveFile already exists at archiveURL, say because of an earlier aborted attempt, the file is overwritten by the copy operation. The overwrite need not be atomic. The implementation can delete the partial archiveFile before copying it anew. An IOException may leave the archiveFile in an inconsistent state. For example, the archive storage may become unavailable, fail, etc. The caller is expected to be handle such failures and not trust the archive file contents (if the file exists at all) following an IOException. If archive storage has the notion of a container, like a directory, or a storage bucket, the implementation may create the container before creating the file, or arrange for the container to be in place before backup is enabled.

Parameters:

localFile - the file to be copied

archiveURL - the target path for the copy; it must be an absolute URL

Returns:

the checksum of the contents of localFile as they were at the time of the copy.

Throws:

InterruptedException - if the copy is interrupted

IOException - if some irrecoverable I/O issue was encountered either while reading or writing the file.

checksum

byte[] checksum(URL archiveURL)
         throws InterruptedException,
                IOException

Returns the checksum computed by reading archiveFile. The file is assumed to be encrypted and compressed in the archive according to the configuration specified by initialize(java.io.File)

Parameters:

archiveURL - the archive file being read to compute the checksum value; it must be an absolute URL

Returns:

the checksum value

Throws:

InterruptedException - if the checksum operation is interrupted

IOException - if some irrecoverable I/O issue was encountered while reading the archiveFile