Package org.tukaani.xz

Class DeltaInputStream

java.lang.Object

java.io.InputStream

org.tukaani.xz.DeltaInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public class DeltaInputStream
extends InputStream

Decodes raw Delta-filtered data (no XZ headers).

The delta filter doesn't change the size of the data and thus it cannot have an end-of-payload marker. It will simply decode until its input stream indicates end of input.

Field Summary

Fields

Modifier and Type	Field	Description
static int	DISTANCE_MAX	Largest supported delta calculation distance.
static int	DISTANCE_MIN	Smallest supported delta calculation distance.

Constructor Summary

Constructors

Constructor	Description
DeltaInputStream(InputStream in, int distance)	Creates a new Delta decoder with the given delta calculation distance.

Method Summary

Modifier and Type	Method	Description
int	available()	Calls in.available().
void	close()	Closes the stream and calls in.close().
int	read()	Decode the next byte from this input stream.
int	read(byte[] buf, int off, int len)	Decode into an array of bytes.

Methods inherited from class java.io.InputStream

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

Methods inherited from class java.lang.Object

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

Field Detail

DISTANCE_MIN

public static final int DISTANCE_MIN

Smallest supported delta calculation distance.

See Also:

Constant Field Values

DISTANCE_MAX

public static final int DISTANCE_MAX

Largest supported delta calculation distance.

See Also:

Constant Field Values

Constructor Detail

DeltaInputStream

public DeltaInputStream(InputStream in,
                        int distance)

Creates a new Delta decoder with the given delta calculation distance.

Parameters:

in - input stream from which Delta filtered data is read

distance - delta calculation distance, must be in the range [DISTANCE_MIN, DISTANCE_MAX]

Method Detail

read

public int read()
         throws IOException

Decode the next byte from this input stream.

Specified by:

read in class InputStream

Returns:

the next decoded byte, or -1 to indicate the end of input on the input stream in

Throws:

IOException - may be thrown by in

read

public int read(byte[] buf,
                int off,
                int len)
         throws IOException

Decode into an array of bytes.

This calls in.read(buf, off, len) and defilters the returned data.

Overrides:

read in class InputStream

Parameters:

buf - target buffer for decoded data

off - start offset in buf

len - maximum number of bytes to read

Returns:

number of bytes read, or -1 to indicate the end of the input stream in

Throws:

XZIOException - if the stream has been closed

IOException - may be thrown by underlaying input stream in

available

public int available()
              throws IOException

Calls in.available().

Overrides:

available in class InputStream

Returns:

the value returned by in.available()

Throws:

IOException

close

public void close()
           throws IOException

Closes the stream and calls in.close(). If the stream was already closed, this does nothing.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class InputStream

Throws:

IOException - if thrown by in.close()