org.rocksdb

Class RestoreBackupableDB

java.lang.Object

org.rocksdb.RocksObject

org.rocksdb.RestoreBackupableDB

public class RestoreBackupableDB
extends RocksObject

This class is used to access information about backups and restore from them.

Note: dispose() must be called before this instance become out-of-scope to release the allocated memory in c++.

Field Summary

Fields inherited from class org.rocksdb.RocksObject

nativeHandle_

Constructor Summary

Constructors

Constructor and Description
RestoreBackupableDB(BackupableDBOptions options) Construct new estoreBackupableDB instance.

Method Summary

Modifier and Type	Method and Description
void	deleteBackup(int backupId) Deletes a specific backup.
void	disposeInternal() Release the memory allocated for the current instance in the c++ side.
void	garbageCollect() Will delete all the files we don't need anymore.
java.util.List<BackupInfo>	getBackupInfos() Returns a list of BackupInfo instances, which describe already made backups.
int[]	getCorruptedBackups() Returns a list of corrupted backup ids.
void	purgeOldBackups(int numBackupsToKeep) Deletes old backups, keeping latest numBackupsToKeep alive.
void	restoreDBFromBackup(long backupId, java.lang.String dbDir, java.lang.String walDir, RestoreOptions restoreOptions) Restore from backup with backup_id.
void	restoreDBFromLatestBackup(java.lang.String dbDir, java.lang.String walDir, RestoreOptions restoreOptions) Restore from the latest backup.

Methods inherited from class org.rocksdb.RocksObject

disOwnNativeHandle, dispose, finalize, isInitialized, isOwningNativeHandle

Methods inherited from class java.lang.Object

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

Constructor Detail

RestoreBackupableDB

public RestoreBackupableDB(BackupableDBOptions options)

Construct new estoreBackupableDB instance.

Parameters:

options - BackupableDBOptions instance

Method Detail

restoreDBFromBackup

public void restoreDBFromBackup(long backupId,
                                java.lang.String dbDir,
                                java.lang.String walDir,
                                RestoreOptions restoreOptions)
                         throws RocksDBException

Restore from backup with backup_id.

Important: If options_.share_table_files == true and you restore DB from some backup that is not the latest, and you start creating new backups from the new DB, they will probably fail.

Example: Let's say you have backups 1, 2, 3, 4, 5 and you restore 3. If you add new data to the DB and try creating a new backup now, the database will diverge from backups 4 and 5 and the new backup will fail. If you want to create new backup, you will first have to delete backups 4 and 5.

Parameters:

backupId - id pointing to backup

dbDir - database directory to restore to

walDir - directory where wal files are located

restoreOptions - RestoreOptions instance.

Throws:

RocksDBException - thrown if error happens in underlying native library.

restoreDBFromLatestBackup

public void restoreDBFromLatestBackup(java.lang.String dbDir,
                                      java.lang.String walDir,
                                      RestoreOptions restoreOptions)
                               throws RocksDBException

Restore from the latest backup.

Parameters:

dbDir - database directory to restore to

walDir - directory where wal files are located

restoreOptions - RestoreOptions instance

Throws:

RocksDBException - thrown if error happens in underlying native library.

purgeOldBackups

public void purgeOldBackups(int numBackupsToKeep)
                     throws RocksDBException

Deletes old backups, keeping latest numBackupsToKeep alive.

Parameters:

numBackupsToKeep - of latest backups to keep

Throws:

RocksDBException - thrown if error happens in underlying native library.

deleteBackup

public void deleteBackup(int backupId)
                  throws RocksDBException

Deletes a specific backup.

Parameters:

backupId - of backup to delete.

Throws:

RocksDBException - thrown if error happens in underlying native library.

getBackupInfos

public java.util.List<BackupInfo> getBackupInfos()

Returns a list of BackupInfo instances, which describe already made backups.

Returns:

List of BackupInfo instances.

getCorruptedBackups

public int[] getCorruptedBackups()

Returns a list of corrupted backup ids. If there is no corrupted backup the method will return an empty list.

Returns:

array of backup ids as int ids.

garbageCollect

public void garbageCollect()
                    throws RocksDBException

Will delete all the files we don't need anymore. It will do the full scan of the files/ directory and delete all the files that are not referenced.

Throws:

RocksDBException - thrown if error happens in underlying native library.

disposeInternal

public void disposeInternal()

Release the memory allocated for the current instance in the c++ side.

Specified by:

disposeInternal in class RocksObject