anon.proxy

Class DecompressionProxyCallback

java.lang.Object

anon.proxy.DecompressionProxyCallback

All Implemented Interfaces:

ProxyCallback

public class DecompressionProxyCallback
extends java.lang.Object
implements ProxyCallback

This class provides functionality for inflating zlib- or gzip-compressed content. Due to http header replacement the JonDo may specify some content-encodings which a client (i.e wget) does not support. In this case the JonDo decodes the content itself using this class. To use its functionality, an object of this class must be registered in the ProxyCallback-framework.

Author:

Simon Pecher

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DecompressionProxyCallback.DecompressionKit
private class	DecompressionProxyCallback.HeaderSplitException

Field Summary

Fields

Modifier and Type	Field and Description
(package private) java.util.Hashtable	decompressionKits
private static int	FCOMMENT
private static int	FEXTRA
private static int	FHCRC these constants are copied from GZIPInputstream because they are declared private there.
private static int	FNAME
static int	MAX_DECOMPRESSION_OUTPUT

Fields inherited from interface anon.proxy.ProxyCallback

STATUS_DELAY, STATUS_FINISHED, STATUS_PROCESSABLE

Constructor Summary

Constructors

Constructor and Description
DecompressionProxyCallback()

Method Summary

Modifier and Type	Method and Description
void	closeRequest(AnonProxyRequest anonRequest) Signals to the ProxyCallback that the given AnonProxyRequest is being closed and all the related stored data can be discarded.
int	decompress(ProxyCallbackBuffer buffer, DecompressionProxyCallback.DecompressionKit decompressionKit, boolean gzipEncoding, boolean start)
int	handleDownstreamChunk(AnonProxyRequest anonRequest, ProxyCallbackBuffer buffer) Processes a chunk of received data, before it is given to the client of the proxy.
int	handleUpstreamChunk(AnonProxyRequest anonRequest, ProxyCallbackBuffer buffer) Processes a chunk of data, before it is sent out.
private int	readGZIPHeader(byte[] data, int offset, int length) slightly modified version of private method GZIPInputStream.readHeader to extract the GZIP header fields.
int	toUnsignedByte(byte nByte)
int	toUnsignedShort(byte lower, byte upper)

Methods inherited from class java.lang.Object

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

Field Detail

decompressionKits

java.util.Hashtable decompressionKits

FHCRC

private static final int FHCRC

these constants are copied from GZIPInputstream because they are declared private there.

See Also:

Constant Field Values

FEXTRA

private static final int FEXTRA

See Also:

Constant Field Values

FNAME

private static final int FNAME

See Also:

Constant Field Values

FCOMMENT

private static final int FCOMMENT

See Also:

Constant Field Values

MAX_DECOMPRESSION_OUTPUT

public static final int MAX_DECOMPRESSION_OUTPUT

See Also:

Constant Field Values

Constructor Detail

DecompressionProxyCallback

public DecompressionProxyCallback()

Method Detail

readGZIPHeader

private int readGZIPHeader(byte[] data,
                           int offset,
                           int length)
                    throws java.util.zip.DataFormatException,
                           DecompressionProxyCallback.HeaderSplitException

slightly modified version of private method GZIPInputStream.readHeader to extract the GZIP header fields. returns the length of the header in bytes.

Throws:

java.util.zip.DataFormatException

DecompressionProxyCallback.HeaderSplitException

toUnsignedShort

public int toUnsignedShort(byte lower,
                           byte upper)

toUnsignedByte

public int toUnsignedByte(byte nByte)

closeRequest

public void closeRequest(AnonProxyRequest anonRequest)

Description copied from interface: ProxyCallback

Signals to the ProxyCallback that the given AnonProxyRequest is being closed and all the related stored data can be discarded.

Specified by:

closeRequest in interface ProxyCallback

decompress

public int decompress(ProxyCallbackBuffer buffer,
                      DecompressionProxyCallback.DecompressionKit decompressionKit,
                      boolean gzipEncoding,
                      boolean start)
               throws java.util.zip.DataFormatException,
                      java.lang.ArrayIndexOutOfBoundsException

Throws:

java.util.zip.DataFormatException

java.lang.ArrayIndexOutOfBoundsException

handleDownstreamChunk

public int handleDownstreamChunk(AnonProxyRequest anonRequest,
                                 ProxyCallbackBuffer buffer)
                          throws ProxyCallbackNotProcessableException

Description copied from interface: ProxyCallback

Processes a chunk of received data, before it is given to the client of the proxy.

Specified by:

handleDownstreamChunk in interface ProxyCallback

Parameters:

anonRequest - The request the data is from.

buffer - Data that is sent to and from the ProxyCallback object.

Returns:

Throws:

ProxyCallbackNotProcessableException - if an error occurred during processing of the data.

handleUpstreamChunk

public int handleUpstreamChunk(AnonProxyRequest anonRequest,
                               ProxyCallbackBuffer buffer)
                        throws ProxyCallbackNotProcessableException

Description copied from interface: ProxyCallback

Processes a chunk of data, before it is sent out.

Specified by:

handleUpstreamChunk in interface ProxyCallback

Parameters:

anonRequest - The request the data is from.

buffer - Data that is sent to and from the ProxyCallback object.

Returns:

Throws:

ProxyCallbackNotProcessableException - if an error occurred during processing of the data.