org.apache.commons.compress.archivers.dump.DumpArchiveEntry

All Implemented Interfaces:: ArchiveEntry

public class DumpArchiveEntry extends Object implements ArchiveEntry

This class represents an entry in a Dump archive. It consists of the entry's header, the entry's File and any extended attributes.

DumpEntries that are created from the header bytes read from an archive are instantiated with the DumpArchiveEntry( byte[] ) constructor. These entries will be used when extracting from or listing the contents of an archive. These entries have their header filled in using the header bytes. They also set the File to null, since they reference an archive entry not a file.

DumpEntries can also be constructed from nothing but a name. This allows the programmer to construct the entry by hand, for instance when only an InputStream is available for writing to the archive, and the header information is constructed from other information. In this case the header fields are set to defaults and the File is set to null.

The C structure for a Dump Entry's header is:

 #define TP_BSIZE    1024          // size of each file block
 #define NTREC       10            // number of blocks to write at once
 #define HIGHDENSITYTREC 32        // number of blocks to write on high-density tapes
 #define TP_NINDIR   (TP_BSIZE/2)  // number if indirect inodes in record
 #define TP_NINOS    (TP_NINDIR / sizeof (int32_t))
 #define LBLSIZE     16
 #define NAMELEN     64

 #define OFS_MAGIC     (int) 60011  // old format magic value
 #define NFS_MAGIC     (int) 60012  // new format magic value
 #define FS_UFS2_MAGIC (int) 0x19540119
 #define CHECKSUM      (int) 84446  // constant used in checksum algorithm

 struct  s_spcl {
   int32_t c_type;             // record type (see below)
   int32_t c_date;             // date of this dump
   int32_t c_ddate;            // date of previous dump
   int32_t c_volume;           // dump volume number
   u_int32_t c_tapea;          // logical block of this record
   dump_ino_t c_ino;           // number of inode
   int32_t c_magic;            // magic number (see above)
   int32_t c_checksum;         // record checksum
 #ifdef  __linux__
   struct  new_bsd_inode c_dinode;
 #else
 #ifdef sunos
   struct  new_bsd_inode c_dinode;
 #else
   struct  dinode  c_dinode;   // ownership and mode of inode
 #endif
 #endif
   int32_t c_count;            // number of valid c_addr entries
   union u_data c_data;        // see above
   char    c_label[LBLSIZE];   // dump label
   int32_t c_level;            // level of this dump
   char    c_filesys[NAMELEN]; // name of dumpped file system
   char    c_dev[NAMELEN];     // name of dumpped device
   char    c_host[NAMELEN];    // name of dumpped host
   int32_t c_flags;            // additional information (see below)
   int32_t c_firstrec;         // first record on volume
   int32_t c_ntrec;            // blocksize on volume
   int32_t c_extattributes;    // additional inode info (see below)
   int32_t c_spare[30];        // reserved for future uses
 } s_spcl;

 //
 // flag values
 //
 #define DR_NEWHEADER     0x0001  // new format tape header
 #define DR_NEWINODEFMT   0x0002  // new format inodes on tape
 #define DR_COMPRESSED    0x0080  // dump tape is compressed
 #define DR_METAONLY      0x0100  // only the metadata of the inode has been dumped
 #define DR_INODEINFO     0x0002  // [SIC] TS_END header contains c_inos information
 #define DR_EXTATTRIBUTES 0x8000

 //
 // extattributes inode info
 //
 #define EXT_REGULAR         0
 #define EXT_MACOSFNDRINFO   1
 #define EXT_MACOSRESFORK    2
 #define EXT_XATTR           3

 // used for EA on tape
 #define EXT2_GOOD_OLD_INODE_SIZE    128
 #define EXT2_XATTR_MAGIC        0xEA020000  // block EA
 #define EXT2_XATTR_MAGIC2       0xEA020001  // in inode EA

The fields in bold are the same for all blocks. (This permitted multiple dumps to be written to a single tape.)

The C structure for the inode (file) information is:

 struct bsdtimeval {           //  **** alpha-*-linux is deviant
   __u32   tv_sec;
   __u32   tv_usec;
 };

 #define NDADDR      12
 #define NIADDR       3

 //
 // This is the new (4.4) BSD inode structure
 // copied from the FreeBSD 2.0 <ufs/ufs/dinode.h> include file
 //
 struct new_bsd_inode {
   __u16       di_mode;           // file type, standard UNIX permissions
   __s16       di_nlink;          // number of hard links to file.
   union {
      __u16       oldids[2];
      __u32       inumber;
   }           di_u;
   u_quad_t    di_size;           // file size
   struct bsdtimeval   di_atime;  // time file was last accessed
   struct bsdtimeval   di_mtime;  // time file was last modified
   struct bsdtimeval   di_ctime;  // time file was created
   __u32       di_db[NDADDR];
   __u32       di_ib[NIADDR];
   __u32       di_flags;          //
   __s32       di_blocks;         // number of disk blocks
   __s32       di_gen;            // generation number
   __u32       di_uid;            // user id (see /etc/passwd)
   __u32       di_gid;            // group id (see /etc/group)
   __s32       di_spare[2];       // unused
 };

It is important to note that the header DOES NOT have the name of the file. It can't since hard links mean that you may have multiple file names for a single physical file. You must read the contents of the directory entries to learn the mapping(s) from file name to inode.

The C structure that indicates if a specific block is a real block that contains data or is a sparse block that is not persisted to the disk is:

 #define TP_BSIZE    1024
 #define TP_NINDIR   (TP_BSIZE/2)

 union u_data {
   char    s_addrs[TP_NINDIR]; // 1 => data; 0 => hole in inode
   int32_t s_inos[TP_NINOS];   // table of first inode on each volume
 } u_data;

This class is not thread-safe

Nested Class Summary

Nested Classes

Modifier and Type

Class

Description

static enum

DumpArchiveEntry.PERMISSION

static enum

DumpArchiveEntry.TYPE
Field Summary

Fields inherited from interface org.apache.commons.compress.archivers.ArchiveEntry
SIZE_UNKNOWN
Constructor Summary

Constructors

Modifier

Constructor

Description

DumpArchiveEntry()

Constructs a default instance.

DumpArchiveEntry(String name, String simpleName)

Constructs a new instance with only names.

protected

DumpArchiveEntry(String name, String simpleName, int ino, DumpArchiveEntry.TYPE type)

Constructs a new instance with name, inode and type.
Method Summary

Modifier and Type

Method

Description

boolean

equals(Object o)

Date

getAccessTime()

Returns the time the file was last accessed.

Date

getCreationTime()

Gets file creation time.

int

getGeneration()

Gets the generation of the file.

int

getGroupId()

Gets the group id

int

getHeaderCount()

Gets the number of records in this segment.

int

getHeaderHoles()

Gets the number of sparse records in this segment.

DumpArchiveConstants.SEGMENT_TYPE

getHeaderType()

Gets the type of the tape segment header.

int

getIno()

Returns the ino of the entry.

Date

getLastModifiedDate()

The last modified date.

int

getMode()

Gets the access permissions on the entry.

String

getName()

Returns the name of the entry.

int

getNlink()

Gets the number of hard links to the entry.

long

getOffset()

Gets the offset within the archive

Set<DumpArchiveEntry.PERMISSION>

getPermissions()

Returns the permissions on the entry.

String

getSimpleName()

Returns the path of the entry.

long

getSize()

Returns the size of the entry.

DumpArchiveEntry.TYPE

getType()

Gets the type of the entry.

int

getUserId()

Gets the user id.

int

getVolume()

Gets the tape volume where this file is located.

int

hashCode()

boolean

isBlkDev()

Is this a block device?

boolean

isChrDev()

Is this a character device?

boolean

isDeleted()

Has this file been deleted?

boolean

isDirectory()

Is this a directory?

boolean

isFifo()

Is this a fifo/pipe?

boolean

isFile()

Is this a regular file?

boolean

isSocket()

Is this a network device?

boolean

isSparseRecord(int idx)

Is this a sparse record?

void

setAccessTime(Date atime)

Sets the time the file was last accessed.

void

setCreationTime(Date ctime)

Sets the file creation time.

void

setDeleted(boolean isDeleted)

Sets whether this file has been deleted.

void

setGeneration(int generation)

Sets the generation of the file.

void

setGroupId(int gid)

Sets the group id.

void

setLastModifiedDate(Date mtime)

Sets the time the file was last modified.

void

setMode(int mode)

Sets the access permissions on the entry.

final void

setName(String name)

Sets the name of the entry.

void

setNlink(int nlink)

Sets the number of hard links.

void

setOffset(long offset)

Sets the offset within the archive.

protected void

setSimpleName(String simpleName)

Sets the path of the entry.

void

setSize(long size)

Sets the size of the entry.

void

setType(DumpArchiveEntry.TYPE type)

Sets the type of the entry.

void

setUserId(int uid)

Sets the user id.

void

setVolume(int volume)

Sets the tape volume.

String

toString()

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.commons.compress.archivers.ArchiveEntry
resolveIn

Constructor Details
- DumpArchiveEntry
  
  public DumpArchiveEntry()
  
  Constructs a default instance.
- DumpArchiveEntry
  
  public DumpArchiveEntry(String name, String simpleName)
  
  Constructs a new instance with only names.
  
  Parameters:
  
  name - path name
  
  simpleName - actual file name.
- DumpArchiveEntry
  
  protected DumpArchiveEntry(String name, String simpleName, int ino, DumpArchiveEntry.TYPE type)
  
  Constructs a new instance with name, inode and type.
  
  Parameters:
  
  name - the name
  
  simpleName - the simple name
  
  ino - the ino
  
  type - the type
Method Details
- equals
  
  public boolean equals(Object o)
  
  Overrides:
  
  equals in class Object
- getAccessTime
  
  public Date getAccessTime()
  
  Returns the time the file was last accessed.
  
  Returns:
  
  the access time
- getCreationTime
  
  public Date getCreationTime()
  
  Gets file creation time.
  
  Returns:
  
  the creation time
- getGeneration
  
  public int getGeneration()
  
  Gets the generation of the file.
  
  Returns:
  
  the generation
- getGroupId
  
  public int getGroupId()
  
  Gets the group id
  
  Returns:
  
  the group id
- getHeaderCount
  
  public int getHeaderCount()
  
  Gets the number of records in this segment.
  
  Returns:
  
  the number of records
- getHeaderHoles
  
  public int getHeaderHoles()
  
  Gets the number of sparse records in this segment.
  
  Returns:
  
  the number of sparse records
- getHeaderType
  
  public DumpArchiveConstants.SEGMENT_TYPE getHeaderType()
  
  Gets the type of the tape segment header.
  
  Returns:
  
  the segment header
- getIno
  
  public int getIno()
  
  Returns the ino of the entry.
  
  Returns:
  
  the ino
- getLastModifiedDate
  
  public Date getLastModifiedDate()
  
  The last modified date.
  
  Specified by:
  
  getLastModifiedDate in interface ArchiveEntry
  
  Returns:
  
  the last modified date
- getMode
  
  public int getMode()
  
  Gets the access permissions on the entry.
  
  Returns:
  
  the access permissions
- getName
  
  public String getName()
  
  Returns the name of the entry.
  This method returns the raw name as it is stored inside of the archive.
  
  Specified by:
  
  getName in interface ArchiveEntry
  
  Returns:
  
  the name of the entry.
- getNlink
  
  public int getNlink()
  
  Gets the number of hard links to the entry.
  
  Returns:
  
  the number of hard links
- getOffset
  
  public long getOffset()
  
  Gets the offset within the archive
  
  Returns:
  
  the offset
- getPermissions
  
  public Set<DumpArchiveEntry.PERMISSION> getPermissions()
  
  Returns the permissions on the entry.
  
  Returns:
  
  the permissions
- getSimpleName
  
  public String getSimpleName()
  
  Returns the path of the entry.
  
  Returns:
  
  the path of the entry.
- getSize
  
  public long getSize()
  
  Returns the size of the entry.
  
  Specified by:
  
  getSize in interface ArchiveEntry
  
  Returns:
  
  the size
- getType
  
  public DumpArchiveEntry.TYPE getType()
  
  Gets the type of the entry.
  
  Returns:
  
  the type
- getUserId
  
  public int getUserId()
  
  Gets the user id.
  
  Returns:
  
  the user id
- getVolume
  
  public int getVolume()
  
  Gets the tape volume where this file is located.
  
  Returns:
  
  the volume
- hashCode
  
  public int hashCode()
  
  Overrides:
  
  hashCode in class Object
- isBlkDev
  
  public boolean isBlkDev()
  
  Is this a block device?
  
  Returns:
  
  whether this is a block device
- isChrDev
  
  public boolean isChrDev()
  
  Is this a character device?
  
  Returns:
  
  whether this is a character device
- isDeleted
  
  public boolean isDeleted()
  
  Has this file been deleted? (On valid on incremental dumps.)
  
  Returns:
  
  whether the file has been deleted
- isDirectory
  
  public boolean isDirectory()
  
  Is this a directory?
  
  Specified by:
  
  isDirectory in interface ArchiveEntry
  
  Returns:
  
  whether this is a directory
- isFifo
  
  public boolean isFifo()
  
  Is this a fifo/pipe?
  
  Returns:
  
  whether this is a fifo
- isFile
  
  public boolean isFile()
  
  Is this a regular file?
  
  Returns:
  
  whether this is a regular file
- isSocket
  
  public boolean isSocket()
  
  Is this a network device?
  
  Returns:
  
  whether this is a socket
- isSparseRecord
  
  public boolean isSparseRecord(int idx)
  
  Is this a sparse record?
  
  Parameters:
  
  idx - index of the record to check
  
  Returns:
  
  whether this is a sparse record
- setAccessTime
  
  public void setAccessTime(Date atime)
  
  Sets the time the file was last accessed.
  
  Parameters:
  
  atime - the access time
- setCreationTime
  
  public void setCreationTime(Date ctime)
  
  Sets the file creation time.
  
  Parameters:
  
  ctime - the creation time
- setDeleted
  
  public void setDeleted(boolean isDeleted)
  
  Sets whether this file has been deleted.
  
  Parameters:
  
  isDeleted - whether the file has been deleted
- setGeneration
  
  public void setGeneration(int generation)
  
  Sets the generation of the file.
  
  Parameters:
  
  generation - the generation
- setGroupId
  
  public void setGroupId(int gid)
  
  Sets the group id.
  
  Parameters:
  
  gid - the group id
- setLastModifiedDate
  
  public void setLastModifiedDate(Date mtime)
  
  Sets the time the file was last modified.
  
  Parameters:
  
  mtime - the last modified time
- setMode
  
  public void setMode(int mode)
  
  Sets the access permissions on the entry.
  
  Parameters:
  
  mode - the access permissions
- setName
  
  public final void setName(String name)
  
  Sets the name of the entry.
  
  Parameters:
  
  name - the name
- setNlink
  
  public void setNlink(int nlink)
  
  Sets the number of hard links.
  
  Parameters:
  
  nlink - the number of hard links
- setOffset
  
  public void setOffset(long offset)
  
  Sets the offset within the archive.
  
  Parameters:
  
  offset - the offset
- setSimpleName
  
  protected void setSimpleName(String simpleName)
  
  Sets the path of the entry.
  
  Parameters:
  
  simpleName - the simple name
- setSize
  
  public void setSize(long size)
  
  Sets the size of the entry.
  
  Parameters:
  
  size - the size
- setType
  
  public void setType(DumpArchiveEntry.TYPE type)
  
  Sets the type of the entry.
  
  Parameters:
  
  type - the type
- setUserId
  
  public void setUserId(int uid)
  
  Sets the user id.
  
  Parameters:
  
  uid - the user id
- setVolume
  
  public void setVolume(int volume)
  
  Sets the tape volume.
  
  Parameters:
  
  volume - the volume
- toString
  
  public String toString()
  
  Overrides:
  
  toString in class Object

Class DumpArchiveEntry

Nested Class Summary

Field Summary

Fields inherited from interface org.apache.commons.compress.archivers.ArchiveEntry

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.apache.commons.compress.archivers.ArchiveEntry

Constructor Details

DumpArchiveEntry

DumpArchiveEntry

DumpArchiveEntry

Method Details

equals

getAccessTime

getCreationTime

getGeneration

getGroupId

getHeaderCount

getHeaderHoles

getHeaderType

getIno

getLastModifiedDate

getMode

getName

getNlink

getOffset

getPermissions

getSimpleName

getSize

getType

getUserId

getVolume

hashCode

isBlkDev

isChrDev

isDeleted

isDirectory

isFifo

isFile

isSocket

isSparseRecord

setAccessTime

setCreationTime

setDeleted

setGeneration

setGroupId

setLastModifiedDate

setMode

setName

setNlink

setOffset

setSimpleName

setSize

setType

setUserId

setVolume

toString