Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 1 | package org.onlab.netty; |
| 2 | |
Madan Jampani | 86ed055 | 2014-10-03 16:45:42 -0700 | [diff] [blame] | 3 | import static com.google.common.base.Preconditions.checkState; |
| 4 | import io.netty.buffer.ByteBuf; |
| 5 | import io.netty.channel.ChannelHandlerContext; |
| 6 | import io.netty.handler.codec.ReplayingDecoder; |
| 7 | |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 8 | import java.util.Arrays; |
| 9 | import java.util.List; |
| 10 | |
Madan Jampani | 938aa43 | 2014-10-04 17:37:23 -0700 | [diff] [blame] | 11 | /** |
| 12 | * Decoder for inbound messages. |
| 13 | */ |
| 14 | public class MessageDecoder extends ReplayingDecoder<DecoderState> { |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 15 | |
| 16 | private final NettyMessagingService messagingService; |
Madan Jampani | 53e44e6 | 2014-10-07 12:39:51 -0700 | [diff] [blame] | 17 | |
| 18 | private static final KryoSerializer SERIALIZER = new KryoSerializer(); |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 19 | |
Madan Jampani | 938aa43 | 2014-10-04 17:37:23 -0700 | [diff] [blame] | 20 | private int contentLength; |
| 21 | |
Madan Jampani | 53e44e6 | 2014-10-07 12:39:51 -0700 | [diff] [blame] | 22 | public MessageDecoder(NettyMessagingService messagingService) { |
Madan Jampani | 938aa43 | 2014-10-04 17:37:23 -0700 | [diff] [blame] | 23 | super(DecoderState.READ_HEADER_VERSION); |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 24 | this.messagingService = messagingService; |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 25 | } |
| 26 | |
| 27 | @Override |
Madan Jampani | 86ed055 | 2014-10-03 16:45:42 -0700 | [diff] [blame] | 28 | protected void decode( |
| 29 | ChannelHandlerContext context, |
| 30 | ByteBuf buffer, |
| 31 | List<Object> out) throws Exception { |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 32 | |
Madan Jampani | 938aa43 | 2014-10-04 17:37:23 -0700 | [diff] [blame] | 33 | switch(state()) { |
| 34 | case READ_HEADER_VERSION: |
| 35 | int headerVersion = buffer.readInt(); |
| 36 | checkState(headerVersion == MessageEncoder.HEADER_VERSION, "Unexpected header version"); |
| 37 | checkpoint(DecoderState.READ_PREAMBLE); |
| 38 | case READ_PREAMBLE: |
| 39 | byte[] preamble = new byte[MessageEncoder.PREAMBLE.length]; |
| 40 | buffer.readBytes(preamble); |
| 41 | checkState(Arrays.equals(MessageEncoder.PREAMBLE, preamble), "Message has wrong preamble"); |
| 42 | checkpoint(DecoderState.READ_CONTENT_LENGTH); |
| 43 | case READ_CONTENT_LENGTH: |
| 44 | contentLength = buffer.readInt(); |
| 45 | checkpoint(DecoderState.READ_SERIALIZER_VERSION); |
| 46 | case READ_SERIALIZER_VERSION: |
| 47 | int serializerVersion = buffer.readInt(); |
| 48 | checkState(serializerVersion == MessageEncoder.SERIALIZER_VERSION, "Unexpected serializer version"); |
| 49 | checkpoint(DecoderState.READ_CONTENT); |
| 50 | case READ_CONTENT: |
Madan Jampani | 53e44e6 | 2014-10-07 12:39:51 -0700 | [diff] [blame] | 51 | InternalMessage message = SERIALIZER.decode(buffer.readBytes(contentLength).nioBuffer()); |
Madan Jampani | 938aa43 | 2014-10-04 17:37:23 -0700 | [diff] [blame] | 52 | message.setMessagingService(messagingService); |
| 53 | out.add(message); |
| 54 | checkpoint(DecoderState.READ_HEADER_VERSION); |
| 55 | break; |
| 56 | default: |
| 57 | checkState(false, "Must not be here"); |
| 58 | } |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 59 | } |
| 60 | } |