Apache Commons Compress 1.26.0 · org.apache.commons.compress.archivers.tar.TarArchiveInputStream

Modifier and Type	Field and Description
private boolean	atEof True if stream is at EOF.
private final int	blockSize The size of a block.
private TarArchiveEntry	currEntry The meta-data about the current entry.
private int	currentSparseInputStreamIndex The index of current input stream being read when reading sparse entries.
private long	entryOffset How far into the entry the stream is at.
private long	entrySize Size of the current .
private Map<String, String>	globalPaxHeaders The global PAX header.
private final List<TarArchiveStructSparse>	globalSparseHeaders The global sparse headers, this is only used in PAX Format 0.X.
private final boolean	lenient
private final byte[]	recordBuffer The buffer to store the TAR header.
private final int	recordSize The size the TAR header.
private static final int	SMALL_BUFFER_SIZE
private final byte[]	smallBuf
private List<InputStream>	sparseInputStreams Input streams for reading sparse entries.
private final ZipEncoding	zipEncoding The encoding of the file.

Access	Constructor and Description
public	TarArchiveInputStream(final InputStream the input stream to use inputStream) Constructs a new instance.
public	TarArchiveInputStream(final InputStream the input stream to use inputStream, final boolean when set to true illegal values for group/userid, mode, device numbers and timestamp will be ignored and the fields set to `TarArchiveEntry#UNKNOWN`. When set to false such illegal fields cause an exception instead. lenient) Constructs a new instance.
public	TarArchiveInputStream(final InputStream the input stream to use inputStream, final int the block size to use blockSize) Constructs a new instance.
public	TarArchiveInputStream(final InputStream the input stream to use inputStream, final int the block size to use blockSize, final int the record size to use recordSize) Constructs a new instance.
public	TarArchiveInputStream(final InputStream the input stream to use inputStream, final int the block size to use blockSize, final int the record size to use recordSize, final String name of the encoding to use for file names encoding) Constructs a new instance.
public	TarArchiveInputStream(final InputStream the input stream to use inputStream, final int the block size to use blockSize, final int the record size to use recordSize, final String name of the encoding to use for file names encoding, final boolean when set to true illegal values for group/userid, mode, device numbers and timestamp will be ignored and the fields set to `TarArchiveEntry#UNKNOWN`. When set to false such illegal fields cause an exception instead. lenient) Constructs a new instance.
public	TarArchiveInputStream(final InputStream the input stream to use inputStream, final int the block size to use blockSize, final String name of the encoding to use for file names encoding) Constructs a new instance.
public	TarArchiveInputStream(final InputStream the input stream to use inputStream, final String name of the encoding to use for file names encoding) Constructs a new instance.

Method Summary

Modifier and Type	Method and Description
private void	applyPaxHeadersToCurrentEntry(final Map<String, String> headers, final List<TarArchiveStructSparse> sparseHeaders)
public int	Returns: The number of available bytes for the current entry. available() Overrides java.io.FilterInputStream.available. Gets the available data that can be read from the current entry in the archive.
private void	buildSparseInputStreams() Build the input streams consisting of all-zero input streams and non-zero input streams.
public boolean	Returns: The implementation will return true if the `ArchiveEntry` is an instance of `TarArchiveEntry` canReadEntryData(final ArchiveEntry the entry to test ae) Overrides org.apache.commons.compress.archivers.ArchiveInputStream.canReadEntryData. Whether this class is able to read the given entry.
public void	close() Overrides java.io.FilterInputStream.close. Implements java.io.Closeable.close. Closes this stream.
private void	consumeRemainderOfLastBlock() This method is invoked once the end of the archive is hit, it tries to consume the remaining bytes under the assumption that the tool creating this archive has padded the last block.
private long	Returns: number of bytes actually skipped getActuallySkipped(final long available bytes returned by inputStream.available() available, final long skipped bytes returned by inputStream.skip() skipped, final long bytes expected to skip expected) For FileInputStream, the skip always return the number you input, so we need the available bytes to determine how many bytes are actually skipped
public TarArchiveEntry	Returns: The current Archive Entry getCurrentEntry() Gets the current TAR Archive Entry that this input stream is processing
protected byte[]	Returns: The next entry in the archive as long name data, or null. getLongNameData() Gets the next entry in this tar archive as long name data.
public TarArchiveEntry	Returns: the next entry, or `null` if there are no more entries getNextEntry() Implements abstract org.apache.commons.compress.archivers.ArchiveInputStream.getNextEntry. Returns the next Archive Entry in this Stream.
public TarArchiveEntry	Returns: The next TarEntry in the archive, or null. getNextTarEntry() Deprecated Use `getNextEntry()`. Gets the next entry in this tar archive.
private byte[]	Returns: The next header in the archive, or null. getRecord() Gets the next record in this tar archive.
public int	Returns: The TarBuffer record size. getRecordSize() Gets the record size being used by this stream's buffer.
protected final boolean	isAtEOF()
private boolean	isDirectory()
protected boolean	Returns: true if the record data is an End of Archive isEOFRecord(final byte[] The record data to check. record) Determine if an archive record indicate End of Archive.
public synchronized void	mark(final int The limit to mark. markLimit) Overrides java.io.FilterInputStream.mark. Since we do not support marking just yet, we do nothing.
public boolean	Returns: False. markSupported() Overrides java.io.FilterInputStream.markSupported. Since we do not support marking just yet, we return false.
public static boolean	Returns: true, if this stream is a tar archive stream, false otherwise matches(final byte[] the bytes to check signature, final int the number of bytes to check length) Checks if the signature matches what is expected for a tar file.
private void	paxHeaders() For PAX Format 0.0, the sparse headers(GNU.sparse.offset and GNU.sparse.numbytes) may appear multi times, and they look like: GNU.sparse.size=size GNU.sparse.numblocks=numblocks repeat numblocks times GNU.sparse.offset=offset GNU.sparse.numbytes=numbytes end repeat For PAX Format 0.1, the sparse headers are stored in a single variable : GNU.sparse.map GNU.sparse.map Map of non-null data chunks.
public int	Returns: The number of bytes read, or -1 at EOF. read(final byte[] The buffer into which to place bytes read. buf, final int The offset at which to place bytes read. offset, int The number of bytes to read. numToRead) Overrides java.io.FilterInputStream.read. Reads bytes from the current tar archive entry.
private void	readGlobalPaxHeaders()
private void	readOldGNUSparse() Adds the sparse chunks from the current entry to the sparse chunks, including any additional sparse entries following the current entry.
protected byte[]	Returns: The record data or null if EOF has been hit. readRecord() Read a record from the input stream and return the data.
private int	Returns: The number of bytes read, or -1 at EOF. readSparse(final byte[] The buffer into which to place bytes read. buf, final int The offset at which to place bytes read. offset, final int The number of bytes to read. numToRead) For sparse tar entries, there are many "holes"(consisting of all 0) in the file.
public synchronized void	reset() Overrides java.io.FilterInputStream.reset. Since we do not support marking just yet, we do nothing.
protected final void	setAtEOF(final boolean b)
protected final void	setCurrentEntry(final TarArchiveEntry e)
public long	Returns: the actual number of bytes skipped. skip(final long the number of bytes to be skipped. n) Overrides java.io.FilterInputStream.skip. Skips over and discards `n` bytes of data from this input stream.
private void	skipRecordPadding() The last record block should be written at the full size, so skip any additional space used to fill a record after an entry.
private long	Returns: actual bytes of data skipped skipSparse(final long bytes of data to skip n) Skip n bytes from current input stream, if the current input stream doesn't have enough data to skip, jump to the next input stream and skip the rest bytes, keep doing this until total n bytes are skipped or the input streams are all skipped
private void	tryToConsumeSecondEOFRecord() Tries to read the next record rewinding the stream if it is not an EOF record.

Inherited from org.apache.commons.compress.archivers.ArchiveInputStream:: count count getBytesRead getCharset getCount pushedBackBytes read

Field Detail

atEof	back to summary
private boolean atEof True if stream is at EOF.

blockSize	back to summary
private final int blockSize The size of a block.

currEntry	back to summary
private TarArchiveEntry currEntry The meta-data about the current entry.

currentSparseInputStreamIndex	back to summary
private int currentSparseInputStreamIndex The index of current input stream being read when reading sparse entries.

entryOffset	back to summary
private long entryOffset How far into the entry the stream is at.

entrySize	back to summary
private long entrySize Size of the current .

globalPaxHeaders	back to summary
private Map<String, String> globalPaxHeaders The global PAX header.

globalSparseHeaders	back to summary
private final List<TarArchiveStructSparse> globalSparseHeaders The global sparse headers, this is only used in PAX Format 0.X.

lenient	back to summary
private final boolean lenient

recordBuffer	back to summary
private final byte[] recordBuffer The buffer to store the TAR header.

recordSize	back to summary
private final int recordSize The size the TAR header.

SMALL_BUFFER_SIZE	back to summary
private static final int SMALL_BUFFER_SIZE

smallBuf	back to summary
private final byte[] smallBuf

sparseInputStreams	back to summary
private List<InputStream> sparseInputStreams Input streams for reading sparse entries.

zipEncoding	back to summary
private final ZipEncoding zipEncoding The encoding of the file.

Constructor Detail

TarArchiveInputStream	back to summary
public TarArchiveInputStream(final InputStream inputStream) Constructs a new instance. Parameters inputStream:InputStream the input stream to use

TarArchiveInputStream

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public TarArchiveInputStream(final InputStream inputStream)

Constructs a new instance.

Parameters

inputStream:InputStream: the input stream to use

TarArchiveInputStream back to summary

TarArchiveInputStream	back to summary
public TarArchiveInputStream(final InputStream inputStream, final boolean lenient) Constructs a new instance. Parameters inputStream:InputStream the input stream to use lenient:boolean when set to true illegal values for group/userid, mode, device numbers and timestamp will be ignored and the fields set to `TarArchiveEntry#UNKNOWN`. When set to false such illegal fields cause an exception instead. Since 1.19

public TarArchiveInputStream(final InputStream inputStream, final boolean lenient)

Constructs a new instance.

Parameters

inputStream:InputStream: the input stream to use
lenient:boolean: when set to true illegal values for group/userid, mode, device numbers and timestamp will be ignored and the fields set to TarArchiveEntry#UNKNOWN. When set to false such illegal fields cause an exception instead.

Since

1.19

TarArchiveInputStream	back to summary
public TarArchiveInputStream(final InputStream inputStream, final int blockSize) Constructs a new instance. Parameters inputStream:InputStream the input stream to use blockSize:int the block size to use

TarArchiveInputStream

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public TarArchiveInputStream(final InputStream inputStream, final int blockSize)

Constructs a new instance.

Parameters

inputStream:InputStream: the input stream to use
blockSize:int: the block size to use

TarArchiveInputStream	back to summary
public TarArchiveInputStream(final InputStream inputStream, final int blockSize, final int recordSize) Constructs a new instance. Parameters inputStream:InputStream the input stream to use blockSize:int the block size to use recordSize:int the record size to use

TarArchiveInputStream

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public TarArchiveInputStream(final InputStream inputStream, final int blockSize, final int recordSize)

Constructs a new instance.

Parameters

inputStream:InputStream: the input stream to use
blockSize:int: the block size to use
recordSize:int: the record size to use

TarArchiveInputStream	back to summary
public TarArchiveInputStream(final InputStream inputStream, final int blockSize, final int recordSize, final String encoding) Constructs a new instance. Parameters inputStream:InputStream the input stream to use blockSize:int the block size to use recordSize:int the record size to use encoding:String name of the encoding to use for file names Since 1.4

TarArchiveInputStream

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public TarArchiveInputStream(final InputStream inputStream, final int blockSize, final int recordSize, final String encoding)

Constructs a new instance.

Parameters

inputStream:InputStream: the input stream to use
blockSize:int: the block size to use
recordSize:int: the record size to use
encoding:String: name of the encoding to use for file names

Since

1.4

TarArchiveInputStream back to summary

TarArchiveInputStream	back to summary
public TarArchiveInputStream(final InputStream inputStream, final int blockSize, final int recordSize, final String encoding, final boolean lenient) Constructs a new instance. Parameters inputStream:InputStream the input stream to use blockSize:int the block size to use recordSize:int the record size to use encoding:String name of the encoding to use for file names lenient:boolean when set to true illegal values for group/userid, mode, device numbers and timestamp will be ignored and the fields set to `TarArchiveEntry#UNKNOWN`. When set to false such illegal fields cause an exception instead. Since 1.19

public TarArchiveInputStream(final InputStream inputStream, final int blockSize, final int recordSize, final String encoding, final boolean lenient)

Constructs a new instance.

Parameters

inputStream:InputStream: the input stream to use
blockSize:int: the block size to use
recordSize:int: the record size to use
encoding:String: name of the encoding to use for file names
lenient:boolean: when set to true illegal values for group/userid, mode, device numbers and timestamp will be ignored and the fields set to TarArchiveEntry#UNKNOWN. When set to false such illegal fields cause an exception instead.

Since

1.19

TarArchiveInputStream	back to summary
public TarArchiveInputStream(final InputStream inputStream, final int blockSize, final String encoding) Constructs a new instance. Parameters inputStream:InputStream the input stream to use blockSize:int the block size to use encoding:String name of the encoding to use for file names Since 1.4

TarArchiveInputStream

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public TarArchiveInputStream(final InputStream inputStream, final int blockSize, final String encoding)

Constructs a new instance.

Parameters

inputStream:InputStream: the input stream to use
blockSize:int: the block size to use
encoding:String: name of the encoding to use for file names

Since

1.4

TarArchiveInputStream	back to summary
public TarArchiveInputStream(final InputStream inputStream, final String encoding) Constructs a new instance. Parameters inputStream:InputStream the input stream to use encoding:String name of the encoding to use for file names Since 1.4

TarArchiveInputStream

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public TarArchiveInputStream(final InputStream inputStream, final String encoding)

Constructs a new instance.

Parameters

inputStream:InputStream: the input stream to use
encoding:String: name of the encoding to use for file names

Since

1.4

Method Detail

applyPaxHeadersToCurrentEntry	back to summary
private void applyPaxHeadersToCurrentEntry(final Map<String, String> headers, final List<TarArchiveStructSparse> sparseHeaders) throws IOException

available	back to summary
public int available() throws IOException Overrides java.io.FilterInputStream.available. Gets the available data that can be read from the current entry in the archive. This does not indicate how much data is left in the entire archive, only in the current entry. This value is determined from the entry's size header field and the amount of data already read from the current entry. Integer.MAX_VALUE is returned in case more than Integer.MAX_VALUE bytes are left in the current entry in the archive. Returns:int The number of available bytes for the current entry. Annotations @Override Exceptions IOException: for signature

available

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public int available() throws IOException

Overrides java.io.FilterInputStream.available.

Gets the available data that can be read from the current entry in the archive. This does not indicate how much data is left in the entire archive, only in the current entry. This value is determined from the entry's size header field and the amount of data already read from the current entry. Integer.MAX_VALUE is returned in case more than Integer.MAX_VALUE bytes are left in the current entry in the archive.

Returns:int

The number of available bytes for the current entry.

Annotations

@Override

Exceptions

IOException:: for signature

buildSparseInputStreams	back to summary
private void buildSparseInputStreams() throws IOException Build the input streams consisting of all-zero input streams and non-zero input streams. When reading from the non-zero input streams, the data is actually read from the original input stream. The size of each input stream is introduced by the sparse headers. NOTE : Some all-zero input streams and non-zero input streams have the size of 0. We DO NOT store the 0 size input streams because they are meaningless.

buildSparseInputStreams

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private void buildSparseInputStreams() throws IOException

Build the input streams consisting of all-zero input streams and non-zero input streams. When reading from the non-zero input streams, the data is actually read from the original input stream. The size of each input stream is introduced by the sparse headers. NOTE : Some all-zero input streams and non-zero input streams have the size of 0. We DO NOT store the 0 size input streams because they are meaningless.

canReadEntryData back to summary

canReadEntryData	back to summary
public boolean canReadEntryData(final ArchiveEntry ae) Overrides org.apache.commons.compress.archivers.ArchiveInputStream.canReadEntryData. Whether this class is able to read the given entry. Parameters ae:ArchiveEntry Doc from org.apache.commons.compress.archivers.ArchiveInputStream.canReadEntryData. the entry to test Returns:boolean The implementation will return true if the `ArchiveEntry` is an instance of `TarArchiveEntry` Annotations @Override

public boolean canReadEntryData(final ArchiveEntry ae)

Overrides org.apache.commons.compress.archivers.ArchiveInputStream.canReadEntryData.

Whether this class is able to read the given entry.

Parameters

ae:ArchiveEntry

Doc from org.apache.commons.compress.archivers.ArchiveInputStream.canReadEntryData.

the entry to test

Returns:boolean

The implementation will return true if the ArchiveEntry is an instance of TarArchiveEntry

Annotations

@Override

close	back to summary
public void close() throws IOException Overrides java.io.FilterInputStream.close. Implements java.io.Closeable.close. Closes this stream. Calls the TarBuffer's close() method. Annotations @Override Exceptions IOException: on error

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public void close() throws IOException

Overrides java.io.FilterInputStream.close.

Implements java.io.Closeable.close.

Closes this stream. Calls the TarBuffer's close() method.

Annotations

@Override

Exceptions

IOException:: on error

consumeRemainderOfLastBlock	back to summary
private void consumeRemainderOfLastBlock() throws IOException This method is invoked once the end of the archive is hit, it tries to consume the remaining bytes under the assumption that the tool creating this archive has padded the last block.

getActuallySkipped	back to summary
private long getActuallySkipped(final long available, final long skipped, final long expected) throws IOException For FileInputStream, the skip always return the number you input, so we need the available bytes to determine how many bytes are actually skipped Parameters available:long available bytes returned by inputStream.available() skipped:long skipped bytes returned by inputStream.skip() expected:long bytes expected to skip Returns:long number of bytes actually skipped Exceptions IOException: if a truncated tar archive is detected

getActuallySkipped

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private long getActuallySkipped(final long available, final long skipped, final long expected) throws IOException

For FileInputStream, the skip always return the number you input, so we need the available bytes to determine how many bytes are actually skipped

Parameters

available:long: available bytes returned by inputStream.available()
skipped:long: skipped bytes returned by inputStream.skip()
expected:long: bytes expected to skip

Returns:long

number of bytes actually skipped

Exceptions

IOException:: if a truncated tar archive is detected

getCurrentEntry	back to summary
public TarArchiveEntry getCurrentEntry() Gets the current TAR Archive Entry that this input stream is processing Returns:TarArchiveEntry The current Archive Entry

getCurrentEntry

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public TarArchiveEntry getCurrentEntry()

Gets the current TAR Archive Entry that this input stream is processing

Returns:TarArchiveEntry: The current Archive Entry

getLongNameData	back to summary
protected byte[] getLongNameData() throws IOException Gets the next entry in this tar archive as long name data. Returns:byte[] The next entry in the archive as long name data, or null. Exceptions IOException: on error

getLongNameData

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protected byte[] getLongNameData() throws IOException

Gets the next entry in this tar archive as long name data.

Returns:byte[]

The next entry in the archive as long name data, or null.

Exceptions

IOException:: on error

getNextEntry back to summary

getNextEntry	back to summary
public TarArchiveEntry getNextEntry() throws IOException Implements abstract org.apache.commons.compress.archivers.ArchiveInputStream.getNextEntry. Returns the next Archive Entry in this Stream. Returns:TarArchiveEntry the next entry, or `null` if there are no more entries Annotations @Override Exceptions IOException: if the next entry could not be read

public TarArchiveEntry getNextEntry() throws IOException

Implements abstract org.apache.commons.compress.archivers.ArchiveInputStream.getNextEntry.

Returns the next Archive Entry in this Stream.

Returns:TarArchiveEntry

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

Annotations

@Override

Exceptions

IOException:: if the next entry could not be read

getNextTarEntry back to summary

getNextTarEntry	back to summary
public TarArchiveEntry getNextTarEntry() throws IOException Deprecated Use `getNextEntry()`. Gets the next entry in this tar archive. This will skip over any remaining data in the current entry, if there is one, and place the input stream at the header of the next entry, and read the header and instantiate a new TarEntry from the header bytes and return that entry. If there are no more entries in the archive, null will be returned to indicate that the end of the archive has been reached. Returns:TarArchiveEntry The next TarEntry in the archive, or null. Annotations @Deprecated Exceptions IOException: on error

public TarArchiveEntry getNextTarEntry() throws IOException

Deprecated

Use getNextEntry().

Gets the next entry in this tar archive. This will skip over any remaining data in the current entry, if there is one, and place the input stream at the header of the next entry, and read the header and instantiate a new TarEntry from the header bytes and return that entry. If there are no more entries in the archive, null will be returned to indicate that the end of the archive has been reached.

Returns:TarArchiveEntry

The next TarEntry in the archive, or null.

Annotations

@Deprecated

Exceptions

IOException:: on error

getRecord back to summary

getRecord	back to summary
private byte[] getRecord() throws IOException Gets the next record in this tar archive. This will skip over any remaining data in the current entry, if there is one, and place the input stream at the header of the next entry. If there are no more entries in the archive, null will be returned to indicate that the end of the archive has been reached. At the same time the `hasHitEOF` marker will be set to true. Returns:byte[] The next header in the archive, or null. Exceptions IOException: on error

private byte[] getRecord() throws IOException

Gets the next record in this tar archive. This will skip over any remaining data in the current entry, if there is one, and place the input stream at the header of the next entry.

If there are no more entries in the archive, null will be returned to indicate that the end of the archive has been reached. At the same time the hasHitEOF marker will be set to true.

Returns:byte[]

The next header in the archive, or null.

Exceptions

IOException:: on error

getRecordSize	back to summary
public int getRecordSize() Gets the record size being used by this stream's buffer. Returns:int The TarBuffer record size.

getRecordSize

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public int getRecordSize()

Gets the record size being used by this stream's buffer.

Returns:int: The TarBuffer record size.

isAtEOF	back to summary
protected final boolean isAtEOF()

isDirectory	back to summary
private boolean isDirectory()

isEOFRecord	back to summary
protected boolean isEOFRecord(final byte[] record) Determine if an archive record indicate End of Archive. End of archive is indicated by a record that consists entirely of null bytes. Parameters record:byte[] The record data to check. Returns:boolean true if the record data is an End of Archive

isEOFRecord

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protected boolean isEOFRecord(final byte[] record)

Determine if an archive record indicate End of Archive. End of archive is indicated by a record that consists entirely of null bytes.

Parameters

record:byte[]: The record data to check.

Returns:boolean

true if the record data is an End of Archive

mark	back to summary
public synchronized void mark(final int markLimit) Overrides java.io.FilterInputStream.mark. Since we do not support marking just yet, we do nothing. Parameters markLimit:int The limit to mark. Annotations @Override

mark

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public synchronized void mark(final int markLimit)

Overrides java.io.FilterInputStream.mark.

Since we do not support marking just yet, we do nothing.

Parameters

markLimit:int: The limit to mark.

Annotations

@Override

markSupported	back to summary
public boolean markSupported() Overrides java.io.FilterInputStream.markSupported. Since we do not support marking just yet, we return false. Returns:boolean False. Annotations @Override

markSupported

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public boolean markSupported()

Overrides java.io.FilterInputStream.markSupported.

Since we do not support marking just yet, we return false.

Returns:boolean

False.

Annotations

@Override

matches	back to summary
public static boolean matches(final byte[] signature, final int length) Checks if the signature matches what is expected for a tar file. Parameters signature:byte[] the bytes to check length:int the number of bytes to check Returns:boolean true, if this stream is a tar archive stream, false otherwise

matches

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

Checks if the signature matches what is expected for a tar file.

Parameters

signature:byte[]: the bytes to check
length:int: the number of bytes to check

Returns:boolean

true, if this stream is a tar archive stream, false otherwise

paxHeaders	back to summary
private void paxHeaders() throws IOException For PAX Format 0.0, the sparse headers(GNU.sparse.offset and GNU.sparse.numbytes) may appear multi times, and they look like: GNU.sparse.size=size GNU.sparse.numblocks=numblocks repeat numblocks times GNU.sparse.offset=offset GNU.sparse.numbytes=numbytes end repeat For PAX Format 0.1, the sparse headers are stored in a single variable : GNU.sparse.map GNU.sparse.map Map of non-null data chunks. It is a string consisting of comma-separated values "offset,size[,offset-1,size-1...]" For PAX Format 1.X: The sparse map itself is stored in the file data block, preceding the actual file data. It consists of a series of decimal numbers delimited by newlines. The map is padded with nulls to the nearest block boundary. The first number gives the number of entries in the map. Following are map entries, each one consisting of two numbers giving the offset and size of the data block it describes.

paxHeaders

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private void paxHeaders() throws IOException

For PAX Format 0.0, the sparse headers(GNU.sparse.offset and GNU.sparse.numbytes) may appear multi times, and they look like: GNU.sparse.size=size GNU.sparse.numblocks=numblocks repeat numblocks times GNU.sparse.offset=offset GNU.sparse.numbytes=numbytes end repeat For PAX Format 0.1, the sparse headers are stored in a single variable : GNU.sparse.map GNU.sparse.map Map of non-null data chunks. It is a string consisting of comma-separated values "offset,size[,offset-1,size-1...]" For PAX Format 1.X: The sparse map itself is stored in the file data block, preceding the actual file data. It consists of a series of decimal numbers delimited by newlines. The map is padded with nulls to the nearest block boundary. The first number gives the number of entries in the map. Following are map entries, each one consisting of two numbers giving the offset and size of the data block it describes.

read	back to summary
public int read(final byte[] buf, final int offset, int numToRead) throws IOException Overrides java.io.FilterInputStream.read. Reads bytes from the current tar archive entry. This method is aware of the boundaries of the current entry in the archive and will deal with them as if they were this stream's start and EOF. Parameters buf:byte[] The buffer into which to place bytes read. offset:int The offset at which to place bytes read. numToRead:int The number of bytes to read. Returns:int The number of bytes read, or -1 at EOF. Annotations @Override Exceptions IOException: on error

read

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public int read(final byte[] buf, final int offset, int numToRead) throws IOException

Overrides java.io.FilterInputStream.read.

Reads bytes from the current tar archive entry. This method is aware of the boundaries of the current entry in the archive and will deal with them as if they were this stream's start and EOF.

Parameters

buf:byte[]: The buffer into which to place bytes read.
offset:int: The offset at which to place bytes read.
numToRead:int: The number of bytes to read.

Returns:int

The number of bytes read, or -1 at EOF.

Annotations

@Override

Exceptions

IOException:: on error

readGlobalPaxHeaders	back to summary
private void readGlobalPaxHeaders() throws IOException

readOldGNUSparse	back to summary
private void readOldGNUSparse() throws IOException Adds the sparse chunks from the current entry to the sparse chunks, including any additional sparse entries following the current entry. Exceptions IOException: on error

readOldGNUSparse

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private void readOldGNUSparse() throws IOException

Adds the sparse chunks from the current entry to the sparse chunks, including any additional sparse entries following the current entry.

Exceptions

IOException:: on error

readRecord	back to summary
protected byte[] readRecord() throws IOException Read a record from the input stream and return the data. Returns:byte[] The record data or null if EOF has been hit. Exceptions IOException: on error

readRecord

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protected byte[] readRecord() throws IOException

Read a record from the input stream and return the data.

Returns:byte[]

The record data or null if EOF has been hit.

Exceptions

IOException:: on error

readSparse

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private int readSparse(final byte[] buf, final int offset, final int numToRead) throws IOException

For sparse tar entries, there are many "holes"(consisting of all 0) in the file. Only the non-zero data is stored in tar files, and they are stored separately. The structure of non-zero data is introduced by the sparse headers using the offset, where a block of non-zero data starts, and numbytes, the length of the non-zero data block. When reading sparse entries, the actual data is read out with "holes" and non-zero data combined together according to the sparse headers.

Parameters

buf:byte[]: The buffer into which to place bytes read.
offset:int: The offset at which to place bytes read.
numToRead:int: The number of bytes to read.

Returns:int

The number of bytes read, or -1 at EOF.

Exceptions

IOException:: on error

reset

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public synchronized void reset()

Overrides java.io.FilterInputStream.reset.

Since we do not support marking just yet, we do nothing.

Annotations

@Override

setAtEOF	back to summary
protected final void setAtEOF(final boolean b)

setCurrentEntry	back to summary
protected final void setCurrentEntry(final TarArchiveEntry e)

skip back to summary

public long skip(final long n) throws IOException

Overrides java.io.FilterInputStream.skip.

Skips over and discards n bytes of data from this input stream. The skip method may, for a variety of reasons, end up skipping over some smaller number of bytes, possibly 0. This may result from any of a number of conditions; reaching end of file or end of entry before n bytes have been skipped; are only two possibilities. The actual number of bytes skipped is returned. If n is negative, no bytes are skipped.

Parameters

n:long: the number of bytes to be skipped.

Returns:long

the actual number of bytes skipped.

Annotations

@Override

Exceptions

IOException:: if a truncated tar archive is detected or some other I/O error occurs

skipRecordPadding

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private void skipRecordPadding() throws IOException

The last record block should be written at the full size, so skip any additional space used to fill a record after an entry.

Exceptions

IOException:: if a truncated tar archive is detected

skipSparse

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private long skipSparse(final long n) throws IOException

Skip n bytes from current input stream, if the current input stream doesn't have enough data to skip, jump to the next input stream and skip the rest bytes, keep doing this until total n bytes are skipped or the input streams are all skipped

Parameters

n:long: bytes of data to skip

Returns:long

actual bytes of data skipped

tryToConsumeSecondEOFRecord

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private void tryToConsumeSecondEOFRecord() throws IOException

Tries to read the next record rewinding the stream if it is not an EOF record.

This is meant to protect against cases where a tar implementation has written only one EOF record when two are expected. Actually this won't help since a non-conforming implementation likely won't fill full blocks consisting of - by default - ten records either so we probably have already read beyond the archive anyway.

public Class TarArchiveInputStream

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