com.partnersoft.io

Class CompressionSwitchingOutputStream

java.lang.Object

java.io.OutputStream

java.io.FilterOutputStream

com.partnersoft.io.CompressionSwitchingOutputStream

All Implemented Interfaces:

java.io.Closeable, java.io.Flushable, java.lang.AutoCloseable

public class CompressionSwitchingOutputStream
extends java.io.FilterOutputStream

An output stream that turns on and off compression on the fly. Must be mated to a CompressionSwitchingInputStream that has its compression switched at the right times to match.

Since compression is block-oriented, this is tricky and doesn't support a lot of things (e.g. marking). Also, be aware that just using this and rapidly toggling compression may not actually help, since compression is best done on large amounts of data. Also, compression costs CPU so way the CPU vs. I/O benefit tradeoff, especially for server-side applications.

Copyright 2000-2014 Partner Software, Inc.

Author:

Paul Reavis

Field Summary

Fields inherited from class java.io.FilterOutputStream

out

Constructor Summary

Constructors

Constructor and Description
CompressionSwitchingOutputStream(java.io.OutputStream out, int compressionLevel) Create a new CompressionSwitchingOutputStream wrapping the given OutputStream and set at the given compression level.

Method Summary

Methods

Modifier and Type	Method and Description
void	close()
int	getCompressionLevel() Get the current compression level.
boolean	isCompressing() Get whether stream is currently compressing.
void	setCompressing(boolean tizit) Set whether stream is currently compressing.
void	setCompressionLevel(int newLevel) Set the current compression level.
void	write(byte[] b)
void	write(byte[] b, int off, int len)
void	write(int byteMe)

Methods inherited from class java.io.FilterOutputStream

flush

Methods inherited from class java.lang.Object

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

Constructor Detail

CompressionSwitchingOutputStream

public CompressionSwitchingOutputStream(java.io.OutputStream out,
                                int compressionLevel)

Create a new CompressionSwitchingOutputStream wrapping the given OutputStream and set at the given compression level.

Parameters:

out - output stream to send compressed data over

compressionLevel - level of compression from 0 to 9

Method Detail

write

public void write(int byteMe)
           throws java.io.IOException

Overrides:

write in class java.io.FilterOutputStream

Throws:

java.io.IOException

write

public void write(byte[] b)
           throws java.io.IOException

Overrides:

write in class java.io.FilterOutputStream

Throws:

java.io.IOException

write

public void write(byte[] b,
         int off,
         int len)
           throws java.io.IOException

Overrides:

write in class java.io.FilterOutputStream

Throws:

java.io.IOException

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Overrides:

close in class java.io.FilterOutputStream

Throws:

java.io.IOException

isCompressing

public boolean isCompressing()

Get whether stream is currently compressing.

Returns:

true if stream is compressing.

setCompressing

public void setCompressing(boolean tizit)
                    throws java.io.IOException

Set whether stream is currently compressing. Does nothing if the stream is already in the specified state.

Parameters:

tizit - whether to turn on compression or turn it off

Throws:

java.io.IOException - if it couldn't make the change

getCompressionLevel

public int getCompressionLevel()

Get the current compression level.

Returns:

current compression level

setCompressionLevel

public void setCompressionLevel(int newLevel)

Set the current compression level. Only takes affect on the next successful setCompressing(true).

Parameters:

newLevel - new compression level