org.getspout.spout.netcache.ChunkNetCache.java Source code

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Here is the source code for org.getspout.spout.netcache.ChunkNetCache.java

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/*
 * This file is part of SpoutPlugin.
 *
 * Copyright (c) 2011 Spout LLC <http://www.spout.org/>
 * SpoutPlugin is licensed under the GNU Lesser General Public License.
 *
 * SpoutPlugin is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * SpoutPlugin is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.getspout.spout.netcache;

import java.io.ByteArrayInputStream;
import java.io.DataInputStream;
import java.io.IOException;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicReference;

import com.google.common.collect.Sets;

import org.getspout.spout.config.ConfigReader;

public class ChunkNetCache {
    private final AtomicReference<byte[]> partitionCache = new AtomicReference<byte[]>();
    private final Set<Long> hashSet;
    private volatile boolean cacheEnabled = false;

    public ChunkNetCache() {
        this(Sets.newSetFromMap(new ConcurrentHashMap<Long, Boolean>()));
    }

    public ChunkNetCache(Set<Long> hashSet) {
        this.hashSet = hashSet;
    }

    public boolean isCacheEnabled() {
        return cacheEnabled;
    }

    public void handleCustomPacket(String channel, byte[] array) {
        if (ConfigReader.isChunkDataCache() && channel.equals("ChkCache:setHash")) {
            cacheEnabled = true;
            if (array != null) {
                DataInputStream din = new DataInputStream(new ByteArrayInputStream(array));
                try {
                    while (true) {
                        long hash = din.readLong();
                        this.hashSet.add(hash);
                    }
                } catch (IOException ee) {
                }
            }
        }
    }

    public byte[] handle(byte[] inflatedBuffer) {
        byte[] partition = partitionCache.getAndSet(null);

        if (partition == null) {
            partition = new byte[2048];
        }

        if (!cacheEnabled) {
            return inflatedBuffer;
        }

        int dataLength = inflatedBuffer.length;
        int segments = dataLength >> 11;
        if ((dataLength & 0x7FF) != 0) {
            segments++;
        }

        int newLength = dataLength + (segments << 3) + 8 + 4 + 1;

        byte[] newBuffer = new byte[newLength];

        for (int i = 0; i < segments; i++) {
            PartitionChunk.copyFromChunkData(inflatedBuffer, i, partition, inflatedBuffer.length);
            long hash = PartitionChunk.hash(partition);
            if (hashSet.add(hash)) {
                PartitionChunk.copyToChunkData(newBuffer, i, partition, dataLength);
            } else {
                PartitionChunk.setHash(newBuffer, i, hash, dataLength);
            }
        }
        long crc = PartitionChunk.hash(inflatedBuffer);
        PartitionChunk.setHash(newBuffer, 0, crc, newLength - 13);
        PartitionChunk.setInt(newBuffer, 0, dataLength, newLength - 5);

        partitionCache.set(partition);

        return newBuffer;
    }
}