org.apache.commons.compress.archivers.ar

Class ArArchiveEntry

java.lang.Object

org.apache.commons.compress.archivers.ar.ArArchiveEntry

All Implemented Interfaces:

ArchiveEntry

public class ArArchiveEntry
extends Object
implements ArchiveEntry

Represents an archive entry in the "ar" format. Each AR archive starts with "!<arch>" followed by a LF. After these 8 bytes the archive entries are listed. The format of an entry header is as it follows:

 START BYTE   END BYTE    NAME                    FORMAT      LENGTH
 0            15          File name               ASCII       16
 16           27          Modification timestamp  Decimal     12
 28           33          Owner ID                Decimal     6
 34           39          Group ID                Decimal     6
 40           47          File mode               Octal       8
 48           57          File size (bytes)       Decimal     10
 58           59          File magic              \140\012    2
 

This specifies that an ar archive entry header contains 60 bytes. Due to the limitation of the file name length to 16 bytes GNU and BSD has their own variants of this format. Currently Commons Compress can read but not write the GNU variant. It fully supports the BSD variant.

See Also:

ar man page

This class is immutable

Field Summary

Fields

Modifier and Type	Field and Description
static String	HEADER The header for each entry
static String	TRAILER The trailer for each entry

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

SIZE_UNKNOWN

Constructor Summary

Constructors

Constructor and Description
ArArchiveEntry(File inputFile, String entryName) Create a new instance using the attributes of the given file
ArArchiveEntry(String name, long length) Create a new instance using a couple of default values.
ArArchiveEntry(String name, long length, int userId, int groupId, int mode, long lastModified) Create a new instance.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj)
int	getGroupId()
long	getLastModified() Last modified time in seconds since the epoch.
Date	getLastModifiedDate() Gets the last modified date of this entry.
long	getLength()
int	getMode()
String	getName() Gets the name of the entry in this archive.
long	getSize() Gets the uncompressed size of this entry.
int	getUserId()
int	hashCode()
boolean	isDirectory() Returns true if this entry refers to a directory.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Field Detail

HEADER

public static final String HEADER

The header for each entry

See Also:

Constant Field Values

TRAILER

public static final String TRAILER

The trailer for each entry

See Also:

Constant Field Values

Constructor Detail

ArArchiveEntry

public ArArchiveEntry(String name,
                      long length)

Create a new instance using a couple of default values.

Sets userId and groupId to 0, the octal file mode to 644 and the last modified time to the current time.

Parameters:

name - name of the entry

length - length of the entry in bytes

ArArchiveEntry

public ArArchiveEntry(String name,
                      long length,
                      int userId,
                      int groupId,
                      int mode,
                      long lastModified)

Create a new instance.

Parameters:

name - name of the entry

length - length of the entry in bytes

userId - numeric user id

groupId - numeric group id

mode - file mode

lastModified - last modified time in seconds since the epoch

ArArchiveEntry

public ArArchiveEntry(File inputFile,
                      String entryName)

Create a new instance using the attributes of the given file

Parameters:

inputFile - the file to create an entry from

entryName - the name of the entry

Method Detail

getSize

public long getSize()

Description copied from interface: ArchiveEntry

Gets the uncompressed size of this entry. May be -1 (SIZE_UNKNOWN) if the size is unknown

Specified by:

getSize in interface ArchiveEntry

Returns:

the uncompressed size of this entry.

getName

public String getName()

Description copied from interface: ArchiveEntry

Gets the name of the entry in this archive. May refer to a file or directory or other item.

Specified by:

getName in interface ArchiveEntry

Returns:

The name of this entry in the archive.

getUserId

public int getUserId()

getGroupId

public int getGroupId()

getMode

public int getMode()

getLastModified

public long getLastModified()

Last modified time in seconds since the epoch.

Returns:

the last modified date

getLastModifiedDate

public Date getLastModifiedDate()

Description copied from interface: ArchiveEntry

Gets the last modified date of this entry.

Specified by:

getLastModifiedDate in interface ArchiveEntry

Returns:

the last modified date of this entry.

getLength

public long getLength()

isDirectory

public boolean isDirectory()

Description copied from interface: ArchiveEntry

Returns true if this entry refers to a directory.

Specified by:

isDirectory in interface ArchiveEntry

Returns:

true if this entry refers to a directory.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object