src/main/java/net/floodlightcontroller/core/internal/OFMessageEncoder.java

/**
 *    Copyright 2011, Big Switch Networks, Inc.
 *    Originally created by David Erickson, Stanford University
 *
 *    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 net.floodlightcontroller.core.internal;

import java.util.List;

import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.handler.codec.oneone.OneToOneEncoder;
import org.openflow.protocol.OFMessage;

/**
 * Encode an openflow message for output into a ChannelBuffer, for use in a
 * netty pipeline
 *
 * @author readams
 */
public class OFMessageEncoder extends OneToOneEncoder {

    @Override
    protected Object encode(ChannelHandlerContext ctx, Channel channel,
                            Object msg) throws Exception {
        if (!(msg instanceof List))
            return msg;

        @SuppressWarnings("unchecked")
        List<OFMessage> msglist = (List<OFMessage>) msg;
        int size = 0;
        for (OFMessage ofm : msglist) {
            size += ofm.getLengthU();
        }

        ChannelBuffer buf = ChannelBuffers.buffer(size);
        ;
        for (OFMessage ofm : msglist) {
            ofm.writeTo(buf);
        }
        return buf;
    }

}