org.virtue.network.session.impl.OnDemandSession.java Source code

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Here is the source code for org.virtue.network.session.impl.OnDemandSession.java

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/**
 * Copyright (c) 2014 Virtue Studios
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package org.virtue.network.session.impl;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;

import java.io.IOException;
import java.util.ArrayDeque;
import java.util.Deque;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.virtue.Virtue;
import org.virtue.cache.Cache;
import org.virtue.engine.service.OnDemandService;
import org.virtue.network.protocol.message.ondemand.OnDemandDropMessage;
import org.virtue.network.protocol.message.ondemand.OnDemandEncryptionMessage;
import org.virtue.network.protocol.message.ondemand.OnDemandInitMessage;
import org.virtue.network.protocol.message.ondemand.OnDemandRequestMessage;
import org.virtue.network.protocol.message.ondemand.OnDemandResponseMessage;
import org.virtue.network.protocol.message.ondemand.OnDemandStateMessage;
import org.virtue.network.protocol.ondemand.OnDemandXorEncoder;
import org.virtue.network.session.Session;

/**
 * 
 * @author Im Frizzy <skype:kfriz1998>
 * @since Sep 4, 2014
 */
public class OnDemandSession extends Session {

    /**
     * The {@link Logger} Instance
     */
    private static final Logger logger = LoggerFactory.getLogger(OnDemandSession.class);

    /**
     * The {@link OnDemandService} used for the ArrayDeque of pending requests
     */
    private final OnDemandService service;

    /**
     * The {@link ArrayDwque} of pending requests
     */
    private final Deque<OnDemandRequestMessage> fileQueue = new ArrayDeque<>();

    /**
     * If the encoder is not sending any requests and no request are being queued
     */
    private boolean idle = true;

    /**
     * The {@link OnDemandSession} constructor
     */
    public OnDemandSession(Channel channel) {
        super(channel);
        this.service = Virtue.getInstance().getEngine().getOnDemandService();
    }

    /**
     * Processes a request and then send the data to the encoder
     */
    public void processFileQueue() {
        OnDemandRequestMessage request;

        synchronized (fileQueue) {
            request = fileQueue.pop();
            if (fileQueue.isEmpty()) {
                idle = true;
            } else {
                service.addPendingSession(this);
                idle = false;
            }
        }

        if (request != null) {
            int type = request.getType();
            int file = request.getFile();

            Cache cache = Virtue.getInstance().getCache();
            ByteBuf buf;

            try {
                if (type == 255 && file == 255) {
                    buf = Unpooled.wrappedBuffer(Virtue.getInstance().getChecksumTable());
                } else {
                    buf = Unpooled.wrappedBuffer(cache.getStore().read(type, file));
                    if (type != 255) {
                        buf = buf.slice(0, buf.readableBytes() - 2);
                    }
                }
                channel.writeAndFlush(new OnDemandResponseMessage(request.isPriority(), type, file, buf));
            } catch (IOException ex) {
                logger.warn("Failed to service file request " + type + ", " + file + ".", ex);
            }
        }
    }

    /* (non-Javadoc)
     * @see org.virtue.network.session.Session#messageReceived(java.lang.Object)
     */
    @Override
    public void messageReceived(Object message) throws IOException {
        if (message instanceof OnDemandRequestMessage) {
            OnDemandRequestMessage request = (OnDemandRequestMessage) message;

            //   System.out.println(request.getType() + ", " + request.getFile());

            synchronized (fileQueue) {
                if (request.isPriority()) {
                    fileQueue.addFirst(request);
                } else {
                    fileQueue.addLast(request);
                }

                if (idle) {
                    service.addPendingSession(this);
                    idle = false;
                }
            }
        } else if (message instanceof OnDemandStateMessage) {
            OnDemandStateMessage state = (OnDemandStateMessage) message;
            if (state.getPadding() != 0L) {
                logger.warn("Invalid state: " + state.getPadding());
                channel.close();
            }
        } else if (message instanceof OnDemandEncryptionMessage) {
            OnDemandEncryptionMessage encryption = (OnDemandEncryptionMessage) message;
            if (encryption.getPadding() == 0) {
                OnDemandXorEncoder encoder = channel.pipeline().get(OnDemandXorEncoder.class);
                encoder.setKey(encryption.getKey());
            }
        } else if (message instanceof OnDemandInitMessage) {
            OnDemandInitMessage init = (OnDemandInitMessage) message;
            if (init.getHeader() != 4) {
                logger.warn("Invalid protocol: " + init.getHeader());
                channel.close();
            }
            if (init.getPadding() != 0) {
                logger.warn("Invalid padding: " + init.getPadding());
                channel.close();
            }
        } else if (message instanceof OnDemandDropMessage) {
            OnDemandDropMessage drop = (OnDemandDropMessage) message;
            if (drop.getHeader() == 0L) {
                logger.warn("Dropping connection: " + channel.remoteAddress());
                fileQueue.clear();
            }
        }
    }

    /* (non-Javadoc)
     * @see org.virtue.network.session.Session#disconnect()
     */
    @Override
    public void disconnect() {
        fileQueue.clear();
    }

}