/*
* Copyright (C) 2008 Trustin Heuiseung Lee
*
* This library 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 2.1 of the License, or (at your option) any later version.
*
* This library 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 library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, 5th Floor, Boston, MA 02110-1301 USA
*/
package net.gleamynode.netty.handler.codec.serialization;
import java.io.StreamCorruptedException;
import net.gleamynode.netty.buffer.ChannelBuffer;
import net.gleamynode.netty.buffer.ChannelBufferInputStream;
import net.gleamynode.netty.channel.Channel;
import net.gleamynode.netty.channel.ChannelHandlerContext;
import net.gleamynode.netty.handler.codec.frame.FrameDecoder;
/**
* @author The Netty Project (netty@googlegroups.com)
* @author Trustin Lee (trustin@gmail.com)
*
* @version $Rev: 552 $, $Date: 2008-07-14 15:55:31 +0900 (Mon, 14 Jul 2008) $
*
*/
public class ObjectDecoder extends FrameDecoder {
private final int maxObjectSize;
public ObjectDecoder() {
this(1048576);
}
public ObjectDecoder(int maxObjectSize) {
this.maxObjectSize = maxObjectSize;
}
@Override
protected Object decode(
ChannelHandlerContext ctx, Channel channel, ChannelBuffer buffer) throws Exception {
if (buffer.readableBytes() < 4) {
return null;
}
int dataLen = buffer.getInt(buffer.readerIndex());
if (dataLen <= 0) {
throw new StreamCorruptedException("invalid data length: " + dataLen);
}
if (dataLen > maxObjectSize) {
throw new StreamCorruptedException(
"data length too big: " + dataLen + " (max: " + maxObjectSize + ')');
}
if (buffer.readableBytes() < dataLen + 4) {
return null;
}
buffer.skipBytes(4);
try {
return new CompactObjectInputStream(new ChannelBufferInputStream(
buffer, buffer.readerIndex(), dataLen)).readObject();
} finally {
buffer.skipBytes(dataLen);
}
}
}