This format is similar to (and contemporary with) TAR but reads the raw filesystem directly. This means that writers are filesystem-specific even though the created archives are filesystem-agnostic.
Unlike other formats DUMP offers clean support for sparse files, extended attributes, and other file metadata. In addition DUMP supports incremental dump files can capture (most) file deletion. It also provides a native form of compression and will soon support native encryption as well.
In practice TAR archives are used for both distribution and backups. DUMP archives are used exclusively for backups.
Like any 30+-year-old application there are a number of variants. For pragmatic reasons we will only support archives with the 'new' tape header and inode formats. Other restrictions:
As of Apache Commons Compress 1.3 support for the dump format is read-only.
| Modifier and Type | Class and Description |
|---|---|
| pack-priv class | Dirent
Directory entry. |
| public class | DumpArchiveConstants
Various constants associated with dump archives. |
| public class | DumpArchiveEntry
This class represents an entry in a Dump archive. |
| public class | DumpArchiveException
Dump Archive Exception |
| public class | DumpArchiveInputStream
The DumpArchiveInputStream reads a UNIX dump archive as an InputStream. |
| public class | DumpArchiveSummary
This class represents identifying information about a Dump archive volume. |
| pack-priv class | DumpArchiveUtil
Various utilities for dump archives. |
| public class | InvalidFormatException
Invalid Format Exception. |
| public class | ShortFileException
Short File Exception. |
| pack-priv class | TapeInputStream
Filter stream that mimics a physical tape drive capable of compressing the data stream. |
| public class | UnrecognizedFormatException
Unrecognized Format Exception. |
| public class | UnsupportedCompressionAlgorithmException
Unsupported compression algorithm. |