de.esprit.appsuite.io.archive.javatar

Class TarInputStream

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

de.esprit.appsuite.io.archive.javatar.TarInputStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public 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(). Kerry Menzel Contributed the code to support file sizes greater than 2GB (longs versus ints).

Version:

$Revision: 1.2 $

Author:

Timothy Gerard Endres,

See Also:

TarBuffer, TarHeader, TarEntry

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	TarInputStream.EntryAdapter
static interface	TarInputStream.EntryFactory This interface is provided, with the method setEntryFactory(), to allow the programmer to have their own TarEntry subclass instantiated for the entries return from getNextEntry().

Field Summary

Fields

Modifier and Type	Field and Description
protected TarBuffer	buffer
protected TarEntry	currEntry
protected boolean	debug
protected TarInputStream.EntryFactory	eFactory
protected long	entryOffset
protected long	entrySize
protected boolean	hasHitEOF
protected byte[]	oneBuf
protected byte[]	readBuf

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

Constructors

Constructor and Description
TarInputStream(java.io.InputStream is)
TarInputStream(java.io.InputStream is, int blockSize)
TarInputStream(java.io.InputStream is, int blockSize, int recordSize)

Method Summary

Methods

Modifier and Type	Method and Description
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 out) Copies the contents of the current tar archive entry directly into an output stream.
long	getEntryPosition() Get the number of bytes into the current TarEntry.
TarEntry	getNextEntry() Get the next entry in this tar archive.
int	getRecordSize() Get the record size being used by this stream's TarBuffer.
long	getStreamPosition() Get the number of bytes into the stream we are currently at.
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[] buf) Reads bytes from the current tar archive entry.
int	read(byte[] buf, int offset, int numToRead) Reads bytes from the current tar archive entry.
void	reset() Since we do not support marking just yet, we do nothing.
void	setBufferDebug(boolean isDebug) Sets the debugging flag in this stream's TarBuffer.
void	setDebug(boolean debugF) Sets the debugging flag.
void	setEntryFactory(TarInputStream.EntryFactory factory) Sets the EntryFactory.
long	skip(long numToSkip) Skip bytes in the input buffer.

Methods inherited from class java.lang.Object

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

Field Detail

debug

protected boolean debug

hasHitEOF

protected boolean hasHitEOF

entrySize

protected long entrySize

entryOffset

protected long entryOffset

oneBuf

protected byte[] oneBuf

readBuf

protected byte[] readBuf

buffer

protected TarBuffer buffer

currEntry

protected TarEntry currEntry

eFactory

protected TarInputStream.EntryFactory eFactory

Constructor Detail

TarInputStream

public TarInputStream(java.io.InputStream is)

TarInputStream

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

TarInputStream

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

Method Detail

setDebug

public void setDebug(boolean debugF)

Sets the debugging flag.

Parameters:

debugF - True to turn on debugging.

setEntryFactory

public void setEntryFactory(TarInputStream.EntryFactory factory)

Sets the EntryFactory.

Parameters:

factory - The factory to be set.

setBufferDebug

public void setBufferDebug(boolean isDebug)

Sets the debugging flag in this stream's TarBuffer.

Parameters:

isDebug - True to turn on debugging.

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

Specified by:

close in interface java.lang.AutoCloseable

Overrides:

close in class java.io.FilterInputStream

Throws:

java.io.IOException

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

skip

public long skip(long 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.

Overrides:

skip in class java.io.FilterInputStream

Parameters:

numToSkip - The number of bytes to skip.

Returns:

The actual number of bytes skipped.

Throws:

java.io.IOException

markSupported

public boolean markSupported()

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

Overrides:

markSupported in class java.io.FilterInputStream

Returns:

False.

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.

reset

public void reset()

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

Overrides:

reset in class java.io.FilterInputStream

getEntryPosition

public long getEntryPosition()

Get the number of bytes into the current TarEntry. This method returns the number of bytes that have been read from the current TarEntry's data.

Returns:

The current entry offset.

getStreamPosition

public long getStreamPosition()

Get the number of bytes into the stream we are currently at. This method accounts for the blocking stream that tar uses, so it represents the actual position in input stream, as opposed to the place where the tar archive parsing is.

Returns:

The current file pointer.

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

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

read

public int read(byte[] buf)
         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:

buf - The buffer into which to place bytes read.

Returns:

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

Throws:

java.io.IOException

read

public int read(byte[] buf,
       int offset,
       int numToRead)
         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:

buf - The buffer into which to place bytes read.

offset - The offset at which to place bytes read.

numToRead - The number of bytes to read.

Returns:

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

Throws:

java.io.IOException

copyEntryContents

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

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

Parameters:

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

Throws:

java.io.IOException