Package org.apache.jackrabbit.oak.segment.spi.persistence

Interface SegmentArchiveManager

All Known Implementing Classes:

AwsArchiveManager, AzureArchiveManager, AzureArchiveManagerV8, CachingArchiveManager, SegmentTarManager, SplitSegmentArchiveManager

public interface SegmentArchiveManager

SegmentArchiveManager provides a low-level access to the segment files (eg. stored in the .tar). It allows to perform a few FS-like operations (delete, rename, copy, etc.) and also opens the segment archives either for reading or reading and writing.

The implementation doesn't need to be thread-safe.

Method Summary

Modifier and Type	Method	Description
void	backup(@NotNull String archiveName, @NotNull String backupArchiveName, @NotNull Set<UUID> recoveredEntries)	Method that is doing a backup of the archive given with archiveName into backupArchiveName.
void	copyFile(@NotNull String from, @NotNull String to)	Copies the archive with all the segments.
@NotNull SegmentArchiveWriter	create(@NotNull String archiveName)	Creates a new archive.
boolean	delete(@NotNull String archiveName)	Deletes the archive if exists.
boolean	exists(@NotNull String archiveName)	Check if archive exists.
@Nullable SegmentArchiveReader	forceOpen(String archiveName)	Opens an archive that wasn't closed correctly.
default boolean	isReadOnly(String archiveName)	Check if the named archive is a read-only archive or not.
@NotNull List<String>	listArchives()	List names of the available .tar archives.
@Nullable SegmentArchiveReader	open(@NotNull String archiveName)	Opens a given archive for reading.
void	recoverEntries(@NotNull String archiveName, @NotNull LinkedHashMap<UUID,byte[]> entries)	Finds all the segments included in the archive.
boolean	renameTo(@NotNull String from, @NotNull String to)	Renames the archive.

Method Detail

listArchives

@NotNull
@NotNull List<String> listArchives()
                            throws IOException

List names of the available .tar archives.

Returns:

archive list

Throws:

IOException

open

@Nullable
@Nullable SegmentArchiveReader open(@NotNull
                                    @NotNull String archiveName)
                             throws IOException

Opens a given archive for reading.

Parameters:

archiveName -

Returns:

the archive reader or null if the archive doesn't exist or doesn't have a valid index

Throws:

IOException

forceOpen

@Nullable
@Nullable SegmentArchiveReader forceOpen(String archiveName)
                                  throws IOException

Opens an archive that wasn't closed correctly.

Parameters:

archiveName -

Returns:

the archive reader or null if the implementation doesn't support opening an unclosed archive

Throws:

IOException

create

@NotNull
@NotNull SegmentArchiveWriter create(@NotNull
                                     @NotNull String archiveName)
                              throws IOException

Creates a new archive.

Parameters:

archiveName -

Returns:

the archive writer

Throws:

IOException

delete

boolean delete(@NotNull
               @NotNull String archiveName)

Deletes the archive if exists.

Parameters:

archiveName -

Returns:

true if the archive was removed, false otherwise

renameTo

boolean renameTo(@NotNull
                 @NotNull String from,
                 @NotNull
                 @NotNull String to)

Renames the archive.

Parameters:

from - the existing archive

to - new name

Returns:

true if the archive was renamed, false otherwise

copyFile

void copyFile(@NotNull
              @NotNull String from,
              @NotNull
              @NotNull String to)
       throws IOException

Copies the archive with all the segments.

Parameters:

from - the existing archive

to - new name

Throws:

IOException

exists

boolean exists(@NotNull
               @NotNull String archiveName)

Check if archive exists.

Parameters:

archiveName - archive to check

Returns:

true if archive exists, false otherwise

recoverEntries

void recoverEntries(@NotNull
                    @NotNull String archiveName,
                    @NotNull
                    @NotNull LinkedHashMap<UUID,byte[]> entries)
             throws IOException

Finds all the segments included in the archive.

Parameters:

archiveName - archive to recover

entries - results will be put there, in the order of presence in the archive

Throws:

IOException

backup

void backup(@NotNull
            @NotNull String archiveName,
            @NotNull
            @NotNull String backupArchiveName,
            @NotNull
            @NotNull Set<UUID> recoveredEntries)
     throws IOException

Method that is doing a backup of the archive given with archiveName into backupArchiveName. In addition, set of UUIDs of recovered segments is provided which can be inspected during backup. Method is invoked during archive recovery procedure and concrete implementation can decide whether original archive should be deleted or modified.

Parameters:

archiveName -

backupArchiveName -

recoveredEntries -

Throws:

IOException

isReadOnly

default boolean isReadOnly(String archiveName)

Check if the named archive is a read-only archive or not. Read-only archives cannot be modified, renamed or removed. E.g. they can not be deleted by compaction even if they no longer contain any referenced segments.

Parameters:

archiveName - The name identifying the archive.

Returns:

true if the named archive is read-only, false otherwise.