com.barchart.netty.common.pipeline.WebSocketConnectedNotifier.java Source code

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Here is the source code for com.barchart.netty.common.pipeline.WebSocketConnectedNotifier.java

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/**
 * Copyright (C) 2011-2014 Barchart, Inc. <http://www.barchart.com/>
 *
 * All rights reserved. Licensed under the OSI BSD License.
 *
 * http://www.opensource.org/licenses/bsd-license.php
 */
package com.barchart.netty.common.pipeline;

import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.handler.codec.http.websocketx.WebSocketClientProtocolHandler;
import io.netty.handler.codec.http.websocketx.WebSocketServerProtocolHandler;

import java.util.ArrayList;
import java.util.List;

/**
 * Blocks downstream channelActive() notifications until a websocket handshake
 * completes.
 */
public class WebSocketConnectedNotifier extends ChannelInboundHandlerAdapter {

    List<Object> messages = new ArrayList<Object>();

    @Override
    public void userEventTriggered(final ChannelHandlerContext ctx, final Object evt) throws Exception {

        if (evt == WebSocketClientProtocolHandler.ClientHandshakeStateEvent.HANDSHAKE_COMPLETE
                || evt == WebSocketServerProtocolHandler.ServerHandshakeStateEvent.HANDSHAKE_COMPLETE) {

            ctx.fireChannelActive();
            ctx.fireUserEventTriggered(evt);

            for (final Object msg : messages)
                ctx.fireChannelRead(msg);

            messages.clear();

            ctx.pipeline().remove(this);

        } else {

            ctx.fireUserEventTriggered(evt);

        }

    }

    @Override
    public void channelActive(final ChannelHandlerContext ctx) throws Exception {
        // Block downstream relay until handshake completes
    }

    @Override
    public void channelRead(final ChannelHandlerContext ctx, final Object msg) {
        // Queue inbound messages; sometimes the first messages can arrive
        // before the handshake complete event so downstream handlers haven't
        // reacted to channelActive() yet
        messages.add(msg);
    }

}