Class RepositionableInputStream

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

java.io.BufferedInputStream

org.archive.io.RepositionableInputStream

All Implemented Interfaces:

RepositionableStream, Closeable, AutoCloseable

public class RepositionableInputStream
extends BufferedInputStream
implements RepositionableStream

Wrapper around an InputStream to make a primitive Repositionable stream. Uses a BufferedInputStream. Calls mark on every read so we'll remember at least the last thing read (You can only backup on the last thing read -- not last 2 or 3 things read). Used by GzippedInputStream when reading streams over a network. Wraps a HTTP, etc., stream so we can back it up if needs be after the GZIP inflater has done a fill of its full buffer though it only needed the first few bytes to finish decompressing the current GZIP member.

TODO: More robust implementation. Tried to use the it.unimi.dsi.io FastBufferdInputStream but relies on FileChannel ByteBuffers and if not present -- as would be the case reading from a network stream, the main application for this instance -- then it expects the underlying stream implements RepositionableStream interface so chicken or egg problem.

Author:

stack

Field Summary

Fields inherited from class java.io.BufferedInputStream

buf, count, marklimit, markpos, pos

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

Constructors

Constructor	Description
RepositionableInputStream(InputStream in)
RepositionableInputStream(InputStream in, int size)

Method Summary

Modifier and Type	Method	Description
protected boolean	isMarked()
void	mark(int readlimit)
long	position()	Returns the current stream position.
void	position(long offset)	Sets the current stream position.
int	read()
int	read(byte[] b)
int	read(byte[] b, int offset, int ct)
void	reset()

Methods inherited from class java.io.BufferedInputStream

available, close, markSupported, skip

Methods inherited from class java.lang.Object

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

Constructor Details

RepositionableInputStream

public RepositionableInputStream(InputStream in)

RepositionableInputStream

public RepositionableInputStream(InputStream in,
 int size)

Method Details

read

public int read(byte[] b)
         throws IOException

Overrides:

read in class FilterInputStream

Throws:

IOException

read

public int read(byte[] b,
 int offset,
 int ct)
         throws IOException

Overrides:

read in class BufferedInputStream

Throws:

IOException

read

public int read()
         throws IOException

Overrides:

read in class BufferedInputStream

Throws:

IOException

position

public void position(long offset)

Description copied from interface: RepositionableStream

Sets the current stream position.

Specified by:

position in interface RepositionableStream

Parameters:

offset - the new stream position.

mark

public void mark(int readlimit)

Overrides:

mark in class BufferedInputStream

reset

public void reset()
           throws IOException

Overrides:

reset in class BufferedInputStream

Throws:

IOException

isMarked

protected boolean isMarked()

position

public long position()

Description copied from interface: RepositionableStream

Returns the current stream position.

Specified by:

position in interface RepositionableStream

Returns:

the current stream position.