org.apache.commons.compress.archivers.tar
Class TarInputStream

java.lang.Object
  java.io.InputStream
      java.io.FilterInputStream
          org.apache.commons.compress.archivers.tar.TarInputStream

All Implemented Interfaces:

java.io.Closeable

public final class TarInputStream
extends java.io.FilterInputStream

The TarInputStream reads a UNIX tar archive as an InputStream. methods are provided to position at each successive entry in the archive, and the read each entry as a normal input stream using read().

Version:

$Revision: 155439 $ $Date: 2006-08-28 08:10:02 +0200 (Mon, 28 Aug 2006) $

Author:

Timothy Gerard Endres, Stefano Mazzocchi, Peter Donald

See Also:

TarInputStream, TarEntry

Field Summary

private TarBuffer	m_buffer
private TarEntry	m_currEntry
private boolean	m_debug
private int	m_entryOffset
private int	m_entrySize
private boolean	m_hasHitEOF
private byte[]	m_oneBuf
private byte[]	m_readBuf

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

TarInputStream(java.io.InputStream input)
Construct a TarInputStream using specified input stream and default block and record sizes.

TarInputStream(java.io.InputStream input, int blockSize)
Construct a TarInputStream using specified input stream, block size and default record sizes.

TarInputStream(java.io.InputStream input, int blockSize, int recordSize)
Construct a TarInputStream using specified input stream, block size and record sizes.

Method Summary

int	available() Get the available data that can be read from the current entry in the archive.
void	close() Closes this stream.
void	copyEntryContents(java.io.OutputStream output) Copies the contents of the current tar archive entry directly into an output stream.
protected void	debug(java.lang.String message) Utility method to do debugging.
TarEntry	getNextEntry() Get the next entry in this tar archive.
int	getRecordSize() Get the record size being used by this stream's TarBuffer.
void	mark(int markLimit) Since we do not support marking just yet, we do nothing.
boolean	markSupported() Since we do not support marking just yet, we return false.
int	read() Reads a byte from the current tar archive entry.
int	read(byte[] buffer) Reads bytes from the current tar archive entry.
int	read(byte[] buffer, int offset, int count) Reads bytes from the current tar archive entry.
void	reset() Since we do not support marking just yet, we do nothing.
void	setDebug(boolean debug) Sets the debugging flag.
void	skip(int numToSkip) Skip bytes in the input buffer.

Methods inherited from class java.io.FilterInputStream

skip

Methods inherited from class java.lang.Object

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

Field Detail

m_buffer

private TarBuffer m_buffer

m_currEntry

private TarEntry m_currEntry

m_debug

private boolean m_debug

m_entryOffset

private int m_entryOffset

m_entrySize

private int m_entrySize

m_hasHitEOF

private boolean m_hasHitEOF

m_oneBuf

private byte[] m_oneBuf

m_readBuf

private byte[] m_readBuf

Constructor Detail

TarInputStream

public TarInputStream(java.io.InputStream input)

Construct a TarInputStream using specified input stream and default block and record sizes.

Parameters:

input - stream to create TarInputStream from

See Also:

TarBuffer.DEFAULT_BLOCKSIZE, TarBuffer.DEFAULT_RECORDSIZE

TarInputStream

public TarInputStream(java.io.InputStream input,
                      int blockSize)

Construct a TarInputStream using specified input stream, block size and default record sizes.

Parameters:

input - stream to create TarInputStream from

blockSize - the block size to use

See Also:

TarBuffer.DEFAULT_RECORDSIZE

TarInputStream

public TarInputStream(java.io.InputStream input,
                      int blockSize,
                      int recordSize)

Construct a TarInputStream using specified input stream, block size and record sizes.

Parameters:

input - stream to create TarInputStream from

blockSize - the block size to use

recordSize - the record size to use

Method Detail

setDebug

public void setDebug(boolean debug)

Sets the debugging flag.

Parameters:

debug - The new Debug value

getNextEntry

public TarEntry getNextEntry()
                      throws java.io.IOException

Get 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:

The next TarEntry in the archive, or null.

Throws:

java.io.IOException - Description of Exception

getRecordSize

public int getRecordSize()

Get the record size being used by this stream's TarBuffer.

Returns:

The TarBuffer record size.

available

public int available()
              throws java.io.IOException

Get 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.

Overrides:

available in class java.io.FilterInputStream

Returns:

The number of available bytes for the current entry.

Throws:

java.io.IOException - when an IO error causes operation to fail

close

public void close()
           throws java.io.IOException

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

Specified by:

close in interface java.io.Closeable

Overrides:

close in class java.io.FilterInputStream

Throws:

java.io.IOException - when an IO error causes operation to fail

copyEntryContents

public void copyEntryContents(java.io.OutputStream output)
                       throws java.io.IOException

Copies the contents of the current tar archive entry directly into an output stream.

Parameters:

output - The OutputStream into which to write the entry's data.

Throws:

java.io.IOException - when an IO error causes operation to fail

mark

public void mark(int markLimit)

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

Overrides:

mark in class java.io.FilterInputStream

Parameters:

markLimit - The limit to mark.

markSupported

public boolean markSupported()

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

Overrides:

markSupported in class java.io.FilterInputStream

Returns:

False.

read

public int read()
         throws java.io.IOException

Reads a byte from the current tar archive entry. This method simply calls read( byte[], int, int ).

Overrides:

read in class java.io.FilterInputStream

Returns:

The byte read, or -1 at EOF.

Throws:

java.io.IOException - when an IO error causes operation to fail

read

public int read(byte[] buffer)
         throws java.io.IOException

Reads bytes from the current tar archive entry. This method simply calls read( byte[], int, int ).

Overrides:

read in class java.io.FilterInputStream

Parameters:

buffer - The buffer into which to place bytes read.

Returns:

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

Throws:

java.io.IOException - when an IO error causes operation to fail

read

public int read(byte[] buffer,
                int offset,
                int count)
         throws java.io.IOException

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.

Overrides:

read in class java.io.FilterInputStream

Parameters:

buffer - The buffer into which to place bytes read.

offset - The offset at which to place bytes read.

count - The number of bytes to read.

Returns:

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

Throws:

java.io.IOException - when an IO error causes operation to fail

reset

public void reset()

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

Overrides:

reset in class java.io.FilterInputStream

skip

public void skip(int numToSkip)
          throws java.io.IOException

Skip bytes in the input buffer. This skips bytes in the current entry's data, not the entire archive, and will stop at the end of the current entry's data if the number to skip extends beyond that point.

Parameters:

numToSkip - The number of bytes to skip.

Throws:

java.io.IOException - when an IO error causes operation to fail

debug

protected void debug(java.lang.String message)

Utility method to do debugging. Capable of being overidden in sub-classes.

Parameters:

message - the message to use in debugging