Class TrivialPreprocessor

  • All Implemented Interfaces:
    TunnelGateway.QueuePreprocessor
    Direct Known Subclasses:
    BatchedPreprocessor, TrivialRouterPreprocessor

    class TrivialPreprocessor
    extends Object
    implements TunnelGateway.QueuePreprocessor
    Do the simplest thing possible for preprocessing - for each message available, turn it into the minimum number of fragmented preprocessed blocks, sending each of those out. This does not coallesce message fragments or delay for more optimal throughput. See FragmentHandler Javadoc for tunnel message fragment format Not instantiated directly except in unit tests; see BatchedPreprocessor
    • Field Detail

      • _log

        protected final Log _log
      • _dataCache

        protected static final ByteCache _dataCache
        Here in tunnels, we take from the cache but never add to it. In other words, we take advantage of other places in the router also using 1024-byte ByteCaches (since ByteCache only maintains once instance for each size) Used in BatchedPreprocessor; see add'l comments there
    • Constructor Detail

      • TrivialPreprocessor

        public TrivialPreprocessor​(RouterContext ctx)
    • Method Detail

      • preprocessQueue

        public boolean preprocessQueue​(List<PendingGatewayMessage> pending,
                                       TunnelGateway.Sender sender,
                                       TunnelGateway.Receiver rec)
        Return true if there were messages remaining, and we should queue up a delayed flush to clear them NOTE: Unused here, see BatchedPreprocessor override, super is not called.
        Specified by:
        preprocessQueue in interface TunnelGateway.QueuePreprocessor
        Parameters:
        pending - list of Pending objects for messages either unsent or partly sent. This list should be update with any values removed (the preprocessor owns the lock) Messages are not removed from the list until actually sent. The status of unsent and partially-sent messages is stored in the Pending structure.
        Returns:
        true if we should delay before preprocessing again
      • notePreprocessing

        protected void notePreprocessing​(long messageId,
                                         int numFragments,
                                         int totalLength,
                                         List<Long> messageIds,
                                         String msg)
      • preprocess

        protected void preprocess​(byte[] fragments,
                                  int fragmentLength)
        Wrap the preprocessed fragments with the necessary padding / checksums to act as a tunnel message.
        Parameters:
        fragmentLength - fragments[0:fragmentLength] is used
      • writeFirstFragment

        protected int writeFirstFragment​(PendingGatewayMessage msg,
                                         byte[] target,
                                         int offset)
      • writeSubsequentFragment

        protected int writeSubsequentFragment​(PendingGatewayMessage msg,
                                              byte[] target,
                                              int offset)
      • getInstructionsSize

        protected static int getInstructionsSize​(PendingGatewayMessage msg)
        Returns:
        generally 3 or 35 or 39 for first fragment, 7 for subsequent fragments. Does NOT include 4 for the message ID if the message will be fragmented; call getInstructionAugmentationSize() for that.
      • getInstructionAugmentationSize

        protected static int getInstructionAugmentationSize​(PendingGatewayMessage msg,
                                                            int offset,
                                                            int instructionsSize)
        Returns:
        0 or 4