Class ProtobufVarint32FrameDecoder

  • All Implemented Interfaces:
    ChannelHandler, ChannelUpstreamHandler, LifeCycleAwareChannelHandler

    public class ProtobufVarint32FrameDecoder
    extends FrameDecoder
    A decoder that splits the received ChannelBuffers dynamically by the value of the Google Protocol Buffers Base 128 Varints integer length field in the message. For example:
     BEFORE DECODE (302 bytes)       AFTER DECODE (300 bytes)
     +--------+---------------+      +---------------+
     | Length | Protobuf Data |----->| Protobuf Data |
     | 0xAC02 |  (300 bytes)  |      |  (300 bytes)  |
     +--------+---------------+      +---------------+
     
    See Also:
    CodedInputStream
    • Constructor Detail

      • ProtobufVarint32FrameDecoder

        public ProtobufVarint32FrameDecoder()
    • Method Detail

      • decode

        protected java.lang.Object decode​(ChannelHandlerContext ctx,
                                          Channel channel,
                                          ChannelBuffer buffer)
                                   throws java.lang.Exception
        Description copied from class: FrameDecoder
        Decodes the received packets so far into a frame. If an sub-class wants to extract a frame out of the buffer it should use the FrameDecoder.extractFrame(ChannelBuffer, int, int) method, to make optimizations easier later.
        Specified by:
        decode in class FrameDecoder
        Parameters:
        ctx - the context of this handler
        channel - the current channel
        buffer - the cumulative buffer of received packets so far. Note that the buffer might be empty, which means you should not make an assumption that the buffer contains at least one byte in your decoder implementation.
        Returns:
        the decoded frame if a full frame was received and decoded. null if there's not enough data in the buffer to decode a frame.
        Throws:
        java.lang.Exception