io.netty.handler.codec.http.websocketx

Class WebSocketClientProtocolHandler

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.handler.codec.MessageToMessageDecoder<WebSocketFrame>

io.netty.handler.codec.http.websocketx.WebSocketClientProtocolHandler

All Implemented Interfaces:

io.netty.channel.ChannelHandler, io.netty.channel.ChannelInboundHandler

public class WebSocketClientProtocolHandler
extends io.netty.handler.codec.MessageToMessageDecoder<WebSocketFrame>

This handler does all the heavy lifting for you to run a websocket client. It takes care of websocket handshaking as well as processing of Ping, Pong frames. Text and Binary data frames are passed to the next handler in the pipeline (implemented by you) for processing. Also the close frame is passed to the next handler as you may want inspect it before close the connection if the handleCloseFrames is false, default is true. This implementation will establish the websocket connection once the connection to the remote server was complete. To know once a handshake was done you can intercept the ChannelInboundHandler.userEventTriggered(ChannelHandlerContext, Object) and check if the event was of type WebSocketClientProtocolHandler.ClientHandshakeStateEvent.HANDSHAKE_ISSUED or WebSocketClientProtocolHandler.ClientHandshakeStateEvent.HANDSHAKE_COMPLETE.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	WebSocketClientProtocolHandler.ClientHandshakeStateEvent Events that are fired to notify about handshake status

Nested classes/interfaces inherited from interface io.netty.channel.ChannelHandler

io.netty.channel.ChannelHandler.Sharable

Constructor Summary

Constructors

Constructor and Description
WebSocketClientProtocolHandler(URI webSocketURL, WebSocketVersion version, String subprotocol, boolean allowExtensions, HttpHeaders customHeaders, int maxFramePayloadLength) Base constructor
WebSocketClientProtocolHandler(URI webSocketURL, WebSocketVersion version, String subprotocol, boolean allowExtensions, HttpHeaders customHeaders, int maxFramePayloadLength, boolean handleCloseFrames) Base constructor
WebSocketClientProtocolHandler(WebSocketClientHandshaker handshaker) Base constructor
WebSocketClientProtocolHandler(WebSocketClientHandshaker handshaker, boolean handleCloseFrames) Base constructor

Method Summary

Modifier and Type	Method and Description
protected void	decode(io.netty.channel.ChannelHandlerContext ctx, WebSocketFrame frame, List<Object> out)
void	exceptionCaught(io.netty.channel.ChannelHandlerContext ctx, Throwable cause)
void	handlerAdded(io.netty.channel.ChannelHandlerContext ctx)
WebSocketClientHandshaker	handshaker() Returns the used handshaker

Methods inherited from class io.netty.handler.codec.MessageToMessageDecoder

acceptInboundMessage, channelRead

Methods inherited from class io.netty.channel.ChannelInboundHandlerAdapter

channelActive, channelInactive, channelReadComplete, channelRegistered, channelUnregistered, channelWritabilityChanged, userEventTriggered

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

ensureNotSharable, handlerRemoved, isSharable

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.netty.channel.ChannelHandler

handlerRemoved

Constructor Detail

WebSocketClientProtocolHandler

public WebSocketClientProtocolHandler(URI webSocketURL,
                                      WebSocketVersion version,
                                      String subprotocol,
                                      boolean allowExtensions,
                                      HttpHeaders customHeaders,
                                      int maxFramePayloadLength,
                                      boolean handleCloseFrames)

Base constructor

Parameters:

webSocketURL - URL for web socket communications. e.g "ws://myhost.com/mypath". Subsequent web socket frames will be sent to this URL.

version - Version of web socket specification to use to connect to the server

subprotocol - Sub protocol request sent to the server.

customHeaders - Map of custom headers to add to the client request

maxFramePayloadLength - Maximum length of a frame's payload

handleCloseFrames - true if close frames should not be forwarded and just close the channel

WebSocketClientProtocolHandler

public WebSocketClientProtocolHandler(URI webSocketURL,
                                      WebSocketVersion version,
                                      String subprotocol,
                                      boolean allowExtensions,
                                      HttpHeaders customHeaders,
                                      int maxFramePayloadLength)

Base constructor

Parameters:

webSocketURL - URL for web socket communications. e.g "ws://myhost.com/mypath". Subsequent web socket frames will be sent to this URL.

version - Version of web socket specification to use to connect to the server

subprotocol - Sub protocol request sent to the server.

customHeaders - Map of custom headers to add to the client request

maxFramePayloadLength - Maximum length of a frame's payload

WebSocketClientProtocolHandler

public WebSocketClientProtocolHandler(WebSocketClientHandshaker handshaker,
                                      boolean handleCloseFrames)

Base constructor

Parameters:

handshaker - The WebSocketClientHandshaker which will be used to issue the handshake once the connection was established to the remote peer.

handleCloseFrames - true if close frames should not be forwarded and just close the channel

WebSocketClientProtocolHandler

public WebSocketClientProtocolHandler(WebSocketClientHandshaker handshaker)

Base constructor

Parameters:

handshaker - The WebSocketClientHandshaker which will be used to issue the handshake once the connection was established to the remote peer.

Method Detail

handshaker

public WebSocketClientHandshaker handshaker()

Returns the used handshaker

decode

protected void decode(io.netty.channel.ChannelHandlerContext ctx,
                      WebSocketFrame frame,
                      List<Object> out)
               throws Exception

Throws:

Exception

handlerAdded

public void handlerAdded(io.netty.channel.ChannelHandlerContext ctx)

Specified by:

handlerAdded in interface io.netty.channel.ChannelHandler

Overrides:

handlerAdded in class io.netty.channel.ChannelHandlerAdapter

exceptionCaught

public void exceptionCaught(io.netty.channel.ChannelHandlerContext ctx,
                            Throwable cause)
                     throws Exception

Specified by:

exceptionCaught in interface io.netty.channel.ChannelHandler

Specified by:

exceptionCaught in interface io.netty.channel.ChannelInboundHandler

Overrides:

exceptionCaught in class io.netty.channel.ChannelInboundHandlerAdapter

Throws:

Exception