jj.http.server.websocket.WebSocketFrameHandler.java Source code

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Here is the source code for jj.http.server.websocket.WebSocketFrameHandler.java

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/*
 *    Copyright 2012 Jason Miller
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package jj.http.server.websocket;

import javax.inject.Inject;
import javax.inject.Singleton;

import jj.engine.HostEvent;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.websocketx.BinaryWebSocketFrame;
import io.netty.handler.codec.http.websocketx.CloseWebSocketFrame;
import io.netty.handler.codec.http.websocketx.PingWebSocketFrame;
import io.netty.handler.codec.http.websocketx.PongWebSocketFrame;
import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
import io.netty.handler.codec.http.websocketx.WebSocketFrame;
import io.netty.handler.codec.http.websocketx.WebSocketServerHandshaker;

/**
 * coordinates the management of websocket frames.  mainly the job here
 * is to turn the netty API into something a little easier to use
 * 
 * @author jason
 *
 */
@Singleton
class WebSocketFrameHandler extends SimpleChannelInboundHandler<WebSocketFrame> {

    private final WebSocketServerHandshaker handshaker;

    private final ConnectionEventExecutor executor;

    private final WebSocketConnection connection;

    private final WebSocketConnectionTracker connectionTracker;

    @Inject
    WebSocketFrameHandler(final WebSocketServerHandshaker handshaker, final ConnectionEventExecutor executor,
            final WebSocketConnection connection, final WebSocketConnectionTracker connectionTracker) {
        this.handshaker = handshaker;
        this.executor = executor;
        this.connection = connection;
        this.connectionTracker = connectionTracker;
    }

    @Override
    public void handlerAdded(ChannelHandlerContext ctx) throws Exception {

        connectionTracker.addConnection(connection);
        connection.webSocketConnectionHost().connected(connection);
        executor.submit(connection, HostEvent.clientConnected.toString(), connection);

        ctx.channel().closeFuture().addListener(new ChannelFutureListener() {

            @Override
            public void operationComplete(ChannelFuture future) throws Exception {
                connectionTracker.removeConnection(connection);
                connection.webSocketConnectionHost().disconnected(connection);
                executor.submit(connection, HostEvent.clientDisconnected.toString(), connection);
            }
        });
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        executor.submit(connection, HostEvent.clientErrored.toString(), connection);
        ctx.close();
    }

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, WebSocketFrame frame) throws Exception {

        connection.markActivity();

        // these are in order!

        if (frame instanceof TextWebSocketFrame) {

            String text = ((TextWebSocketFrame) frame).text();
            if ("jj-hi".equals(text)) {
                ctx.writeAndFlush(new TextWebSocketFrame("jj-yo"));
            } else {
                if (!connection.webSocketConnectionHost().message(connection, text)) {
                    // TODO couldn't read the message! do what, though?
                }
            }

        } else if (frame instanceof PingWebSocketFrame) {

            ctx.writeAndFlush(new PongWebSocketFrame(frame.content().retain()));

        } else if (frame instanceof PongWebSocketFrame) {

            // this should never happen

        } else if (frame instanceof BinaryWebSocketFrame) {

            // need to understand this

        } else if (frame instanceof CloseWebSocketFrame) {

            handshaker.close(ctx.channel(), (CloseWebSocketFrame) frame.retain());

        }
    }
}