Package org.apache.commons.compress.archivers.ar

Class ArArchiveInputStream

java.lang.Object

java.io.InputStream

org.apache.commons.compress.archivers.ArchiveInputStream

org.apache.commons.compress.archivers.ar.ArArchiveInputStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class ArArchiveInputStream
extends ArchiveInputStream

Implements the "ar" archive format as an input stream.

Field Summary

Fields

Modifier and Type	Field	Description
private static java.lang.String	BSD_LONGNAME_PATTERN
(package private) static java.lang.String	BSD_LONGNAME_PREFIX
private static int	BSD_LONGNAME_PREFIX_LEN
private boolean	closed
private ArArchiveEntry	currentEntry
private long	entryOffset
private static int	FILE_MODE_LEN
private static int	FILE_MODE_OFFSET
private static java.lang.String	GNU_LONGNAME_PATTERN
private static java.lang.String	GNU_STRING_TABLE_NAME
private static int	GROUP_ID_LEN
private static int	GROUP_ID_OFFSET
private java.io.InputStream	input
private static int	LAST_MODIFIED_LEN
private static int	LAST_MODIFIED_OFFSET
private static int	LENGTH_LEN
private static int	LENGTH_OFFSET
private byte[]	metaData
private static int	NAME_LEN
private static int	NAME_OFFSET
private byte[]	namebuffer
private long	offset
private static int	USER_ID_LEN
private static int	USER_ID_OFFSET

Constructor Summary

Constructors

Constructor	Description
ArArchiveInputStream(java.io.InputStream pInput)	Constructs an Ar input stream with the referenced stream

Method Summary

Modifier and Type	Method	Description
private int	asInt(byte[] byteArray, int offset, int len)
private int	asInt(byte[] byteArray, int offset, int len, boolean treatBlankAsZero)
private int	asInt(byte[] byteArray, int offset, int len, int base)
private int	asInt(byte[] byteArray, int offset, int len, int base, boolean treatBlankAsZero)
private long	asLong(byte[] byteArray, int offset, int len)
void	close()
private java.lang.String	getBSDLongName(java.lang.String bsdLongName)	Reads the real name from the current stream assuming the very first bytes to be read are the real file name.
private java.lang.String	getExtendedName(int offset)	Get an extended name from the GNU extended name buffer.
ArArchiveEntry	getNextArEntry()	Returns the next AR entry in this stream.
ArchiveEntry	getNextEntry()	Returns the next Archive Entry in this Stream.
private static boolean	isBSDLongName(java.lang.String name)	Does the name look like it is a long name (or a name containing spaces) as encoded by BSD ar?
private boolean	isGNULongName(java.lang.String name)	Does the name look like it is a long name (or a name containing spaces) as encoded by SVR4/GNU ar?
private static boolean	isGNUStringTable(java.lang.String name)	Is this the name of the "Archive String Table" as used by SVR4/GNU to store long file names?
static boolean	matches(byte[] signature, int length)	Checks if the signature matches ASCII "!<arch>" followed by a single LF control character
int	read(byte[] b, int off, int len)
private ArArchiveEntry	readGNUStringTable(byte[] length, int offset, int len)	Reads the GNU archive String Table.
private void	trackReadBytes(long read)

Methods inherited from class org.apache.commons.compress.archivers.ArchiveInputStream

canReadEntryData, count, count, getBytesRead, getCount, pushedBackBytes, read

Methods inherited from class java.io.InputStream

available, mark, markSupported, nullInputStream, read, readAllBytes, readNBytes, readNBytes, reset, skip, transferTo

Methods inherited from class java.lang.Object

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

Field Detail

input

private final java.io.InputStream input

offset

private long offset

closed

private boolean closed

currentEntry

private ArArchiveEntry currentEntry

namebuffer

private byte[] namebuffer

entryOffset

private long entryOffset

NAME_OFFSET

private static final int NAME_OFFSET

See Also:

Constant Field Values

NAME_LEN

private static final int NAME_LEN

See Also:

Constant Field Values

LAST_MODIFIED_OFFSET

private static final int LAST_MODIFIED_OFFSET

See Also:

Constant Field Values

LAST_MODIFIED_LEN

private static final int LAST_MODIFIED_LEN

See Also:

Constant Field Values

USER_ID_OFFSET

private static final int USER_ID_OFFSET

See Also:

Constant Field Values

USER_ID_LEN

private static final int USER_ID_LEN

See Also:

Constant Field Values

GROUP_ID_OFFSET

private static final int GROUP_ID_OFFSET

See Also:

Constant Field Values

GROUP_ID_LEN

private static final int GROUP_ID_LEN

See Also:

Constant Field Values

FILE_MODE_OFFSET

private static final int FILE_MODE_OFFSET

See Also:

Constant Field Values

FILE_MODE_LEN

private static final int FILE_MODE_LEN

See Also:

Constant Field Values

LENGTH_OFFSET

private static final int LENGTH_OFFSET

See Also:

Constant Field Values

LENGTH_LEN

private static final int LENGTH_LEN

See Also:

Constant Field Values

metaData

private final byte[] metaData

BSD_LONGNAME_PREFIX

static final java.lang.String BSD_LONGNAME_PREFIX

See Also:

Constant Field Values

BSD_LONGNAME_PREFIX_LEN

private static final int BSD_LONGNAME_PREFIX_LEN

BSD_LONGNAME_PATTERN

private static final java.lang.String BSD_LONGNAME_PATTERN

See Also:

Constant Field Values

GNU_STRING_TABLE_NAME

private static final java.lang.String GNU_STRING_TABLE_NAME

See Also:

Constant Field Values

GNU_LONGNAME_PATTERN

private static final java.lang.String GNU_LONGNAME_PATTERN

See Also:

Constant Field Values

Constructor Detail

ArArchiveInputStream

public ArArchiveInputStream(java.io.InputStream pInput)

Constructs an Ar input stream with the referenced stream

Parameters:

pInput - the ar input stream

Method Detail

getNextArEntry

public ArArchiveEntry getNextArEntry()
                              throws java.io.IOException

Returns the next AR entry in this stream.

Returns:

the next AR entry.

Throws:

java.io.IOException - if the entry could not be read

getExtendedName

private java.lang.String getExtendedName(int offset)
                                  throws java.io.IOException

Get an extended name from the GNU extended name buffer.

Parameters:

offset - pointer to entry within the buffer

Returns:

the extended file name; without trailing "/" if present.

Throws:

java.io.IOException - if name not found or buffer not set up

asLong

private long asLong(byte[] byteArray,
                    int offset,
                    int len)

asInt

private int asInt(byte[] byteArray,
                  int offset,
                  int len)

asInt

private int asInt(byte[] byteArray,
                  int offset,
                  int len,
                  boolean treatBlankAsZero)

asInt

private int asInt(byte[] byteArray,
                  int offset,
                  int len,
                  int base)

asInt

private int asInt(byte[] byteArray,
                  int offset,
                  int len,
                  int base,
                  boolean treatBlankAsZero)

getNextEntry

public ArchiveEntry getNextEntry()
                          throws java.io.IOException

Description copied from class: ArchiveInputStream

Returns the next Archive Entry in this Stream.

Specified by:

getNextEntry in class ArchiveInputStream

Returns:

the next entry, or null if there are no more entries

Throws:

java.io.IOException - if the next entry could not be read

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface java.io.Closeable

Overrides:

close in class java.io.InputStream

Throws:

java.io.IOException

read

public int read(byte[] b,
                int off,
                int len)
         throws java.io.IOException

Overrides:

read in class java.io.InputStream

Throws:

java.io.IOException

matches

public static boolean matches(byte[] signature,
                              int length)

Checks if the signature matches ASCII "!<arch>" followed by a single LF control character

Parameters:

signature - the bytes to check

length - the number of bytes to check

Returns:

true, if this stream is an Ar archive stream, false otherwise

isBSDLongName

private static boolean isBSDLongName(java.lang.String name)

Does the name look like it is a long name (or a name containing spaces) as encoded by BSD ar?

From the FreeBSD ar(5) man page:

 BSD   In the BSD variant, names that are shorter than 16
       characters and without embedded spaces are stored
       directly in this field.  If a name has an embedded
       space, or if it is longer than 16 characters, then
       the string "#1/" followed by the decimal represen-
       tation of the length of the file name is placed in
       this field. The actual file name is stored immedi-
       ately after the archive header.  The content of the
       archive member follows the file name.  The ar_size
       field of the header (see below) will then hold the
       sum of the size of the file name and the size of
       the member.
 

Since:

1.3

getBSDLongName

private java.lang.String getBSDLongName(java.lang.String bsdLongName)
                                 throws java.io.IOException

Reads the real name from the current stream assuming the very first bytes to be read are the real file name.

Throws:

java.io.IOException

Since:

1.3

See Also:

isBSDLongName(java.lang.String)

isGNUStringTable

private static boolean isGNUStringTable(java.lang.String name)

Is this the name of the "Archive String Table" as used by SVR4/GNU to store long file names?

GNU ar stores multiple extended file names in the data section of a file with the name "//", this record is referred to by future headers.

A header references an extended file name by storing a "/" followed by a decimal offset to the start of the file name in the extended file name data section.

The format of the "//" file itself is simply a list of the long file names, each separated by one or more LF characters. Note that the decimal offsets are number of characters, not line or string number within the "//" file.

trackReadBytes

private void trackReadBytes(long read)

readGNUStringTable

private ArArchiveEntry readGNUStringTable(byte[] length,
                                          int offset,
                                          int len)
                                   throws java.io.IOException

Reads the GNU archive String Table.

Throws:

java.io.IOException

See Also:

isGNUStringTable(java.lang.String)

isGNULongName

private boolean isGNULongName(java.lang.String name)

Does the name look like it is a long name (or a name containing spaces) as encoded by SVR4/GNU ar?

See Also:

isGNUStringTable(java.lang.String)