Class WebSocket08FrameDecoder

java.lang.Object

org.jboss.netty.channel.SimpleChannelUpstreamHandler

org.jboss.netty.handler.codec.frame.FrameDecoder

org.jboss.netty.handler.codec.replay.ReplayingDecoder<WebSocket08FrameDecoder.State>

org.jboss.netty.handler.codec.http.websocketx.WebSocket08FrameDecoder

All Implemented Interfaces:

ChannelHandler, ChannelUpstreamHandler, LifeCycleAwareChannelHandler

Direct Known Subclasses:

WebSocket07FrameDecoder, WebSocket13FrameDecoder

public class WebSocket08FrameDecoder
extends ReplayingDecoder<WebSocket08FrameDecoder.State>

Decodes a web socket frame from wire protocol version 8 format. This code was forked from webbit and modified.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	WebSocket08FrameDecoder.State

Nested classes/interfaces inherited from interface ChannelHandler

ChannelHandler.Sharable

Field Summary

Fields

Modifier and Type	Field	Description
private final boolean	allowExtensions
private int	fragmentedFramesCount
private boolean	frameFinalFlag
private int	frameOpcode
private ChannelBuffer	framePayload
private int	framePayloadBytesRead
private long	framePayloadLength
private int	frameRsv
private static final InternalLogger	logger
private final boolean	maskedPayload
private ChannelBuffer	maskingKey
private final long	maxFramePayloadLength
private static final byte	OPCODE_BINARY
private static final byte	OPCODE_CLOSE
private static final byte	OPCODE_CONT
private static final byte	OPCODE_PING
private static final byte	OPCODE_PONG
private static final byte	OPCODE_TEXT
private boolean	receivedClosingHandshake
private Utf8Validator	utf8Validator

Fields inherited from class FrameDecoder

cumulation, DEFAULT_MAX_COMPOSITEBUFFER_COMPONENTS

Constructor Summary

Constructors

Constructor	Description
WebSocket08FrameDecoder(boolean maskedPayload, boolean allowExtensions)	Constructor with default values
WebSocket08FrameDecoder(boolean maskedPayload, boolean allowExtensions, long maxFramePayloadLength)	Constructor

Method Summary

Modifier and Type	Method	Description
protected void	checkCloseFrameBody(Channel channel, ChannelBuffer buffer)
private void	checkUTF8String(Channel channel, byte[] bytes)
protected Object	decode(ChannelHandlerContext ctx, Channel channel, ChannelBuffer buffer, WebSocket08FrameDecoder.State state)	Decodes the received packets so far into a frame.
private void	protocolViolation(Channel channel, String reason)
private void	protocolViolation(Channel channel, CorruptedFrameException ex)
private static int	toFrameLength(long l)
private void	unmask(ChannelBuffer frame)

Methods inherited from class ReplayingDecoder

checkpoint, checkpoint, cleanup, decode, decodeLast, decodeLast, getState, internalBuffer, messageReceived, setState

Methods inherited from class FrameDecoder

actualReadableBytes, afterAdd, afterRemove, appendToCumulation, beforeAdd, beforeRemove, channelClosed, channelDisconnected, exceptionCaught, extractFrame, getMaxCumulationBufferCapacity, getMaxCumulationBufferComponents, isUnfold, newCumulationBuffer, replace, setMaxCumulationBufferCapacity, setMaxCumulationBufferComponents, setUnfold, unfoldAndFireMessageReceived, updateCumulation

Methods inherited from class SimpleChannelUpstreamHandler

channelBound, channelConnected, channelInterestChanged, channelOpen, channelUnbound, childChannelClosed, childChannelOpen, handleUpstream, writeComplete

Methods inherited from class Object

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

Field Details

logger

private static final InternalLogger logger

OPCODE_CONT

private static final byte OPCODE_CONT

See Also:

• Constant Field Values

OPCODE_TEXT

private static final byte OPCODE_TEXT

See Also:

• Constant Field Values

OPCODE_BINARY

private static final byte OPCODE_BINARY

See Also:

• Constant Field Values

OPCODE_CLOSE

private static final byte OPCODE_CLOSE

See Also:

• Constant Field Values

OPCODE_PING

private static final byte OPCODE_PING

See Also:

• Constant Field Values

OPCODE_PONG

private static final byte OPCODE_PONG

See Also:

• Constant Field Values

utf8Validator

private Utf8Validator utf8Validator

fragmentedFramesCount

private int fragmentedFramesCount

maxFramePayloadLength

private final long maxFramePayloadLength

frameFinalFlag

private boolean frameFinalFlag

frameRsv

private int frameRsv

frameOpcode

private int frameOpcode

framePayloadLength

private long framePayloadLength

framePayload

private ChannelBuffer framePayload

framePayloadBytesRead

private int framePayloadBytesRead

maskingKey

private ChannelBuffer maskingKey

allowExtensions

private final boolean allowExtensions

maskedPayload

private final boolean maskedPayload

receivedClosingHandshake

private boolean receivedClosingHandshake

Constructor Details

WebSocket08FrameDecoder

public WebSocket08FrameDecoder(boolean maskedPayload,
 boolean allowExtensions)

Constructor with default values

Parameters:

maskedPayload - Web socket servers must set this to true processed incoming masked payload. Client implementations must set this to false.

allowExtensions - Flag to allow reserved extension bits to be used or not

WebSocket08FrameDecoder

public WebSocket08FrameDecoder(boolean maskedPayload,
 boolean allowExtensions,
 long maxFramePayloadLength)

Constructor

Parameters:

maskedPayload - Web socket servers must set this to true processed incoming masked payload. Client implementations must set this to false.

allowExtensions - Flag to allow reserved extension bits to be used or not

maxFramePayloadLength - Maximum length of a frame's payload. Setting this to an appropriate value for you application helps check for denial of services attacks.

Method Details

decode

protected Object decode(ChannelHandlerContext ctx,
 Channel channel,
 ChannelBuffer buffer,
 WebSocket08FrameDecoder.State state)
                 throws Exception

Description copied from class: ReplayingDecoder

Decodes the received packets so far into a frame.

Specified by:

decode in class ReplayingDecoder<WebSocket08FrameDecoder.State>

Parameters:

ctx - the context of this handler

channel - the current channel

buffer - the cumulative buffer of received packets so far. Note that the buffer might be empty, which means you should not make an assumption that the buffer contains at least one byte in your decoder implementation.

state - the current decoder state (null if unused)

Returns:

the decoded frame

Throws:

Exception

unmask

private void unmask(ChannelBuffer frame)

protocolViolation

private void protocolViolation(Channel channel,
 String reason)
                        throws CorruptedFrameException

Throws:

CorruptedFrameException

protocolViolation

private void protocolViolation(Channel channel,
 CorruptedFrameException ex)
                        throws CorruptedFrameException

Throws:

CorruptedFrameException

toFrameLength

private static int toFrameLength(long l)
                          throws TooLongFrameException

Throws:

TooLongFrameException

checkUTF8String

private void checkUTF8String(Channel channel,
 byte[] bytes)
                      throws CorruptedFrameException

Throws:

CorruptedFrameException

checkCloseFrameBody

protected void checkCloseFrameBody(Channel channel,
 ChannelBuffer buffer)
                            throws CorruptedFrameException

Throws:

CorruptedFrameException