Rfc5425Encoder.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.camel.component.syslog.netty;

import java.nio.charset.Charset;
import java.util.List;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufAllocator;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandler.Sharable;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.MessageToMessageEncoder;


@Sharable
public class Rfc5425Encoder extends MessageToMessageEncoder<ByteBuf> {

    @Override
    protected void encode(ChannelHandlerContext ctx, ByteBuf byteBuf, List<Object> out) throws Exception {
        if (byteBuf.isReadable()) {
            int length = byteBuf.readableBytes();

            String headerString = length + " ";

            ByteBuf header = ByteBufAllocator.DEFAULT.buffer(headerString.getBytes(Charset.forName("UTF8")).length);
            header.writeBytes(headerString.getBytes(Charset.forName("UTF8")));

            Unpooled.buffer();

            byteBuf.retain();
            out.add(Unpooled.wrappedBuffer(header, byteBuf));
        }
    }
}