HandleImpl Class — netty Architecture

Source Code

transport/src/main/java/io/netty/channel/DefaultMaxBytesRecvByteBufAllocator.java lines 35–104

    private final class HandleImpl implements ExtendedHandle {
        private int individualReadMax;
        private int bytesToRead;
        private int lastBytesRead;
        private int attemptBytesRead;
        private final UncheckedBooleanSupplier defaultMaybeMoreSupplier = new UncheckedBooleanSupplier() {
            @Override
            public boolean get() {
                return attemptBytesRead == lastBytesRead;
            }
        };

        @Override
        public ByteBuf allocate(ByteBufAllocator alloc) {
            return alloc.ioBuffer(guess());
        }

        @Override
        public int guess() {
            return Math.min(individualReadMax, bytesToRead);
        }

        @Override
        public void reset(ChannelConfig config) {
            bytesToRead = maxBytesPerRead();
            individualReadMax = maxBytesPerIndividualRead();
        }

        @Override
        public void incMessagesRead(int amt) {
        }

        @Override
        public void lastBytesRead(int bytes) {
            lastBytesRead = bytes;
            // Ignore if bytes is negative, the interface contract states it will be detected externally after call.
            // The value may be "invalid" after this point, but it doesn't matter because reading will be stopped.
            bytesToRead -= bytes;
        }

        @Override
        public int lastBytesRead() {
            return lastBytesRead;
        }

        @Override
        public boolean continueReading() {
            return continueReading(defaultMaybeMoreSupplier);
        }

        @Override
        public boolean continueReading(UncheckedBooleanSupplier maybeMoreDataSupplier) {
            // Keep reading if we are allowed to read more bytes, and our last read filled up the buffer we provided.
            return bytesToRead > 0 && maybeMoreDataSupplier.get();
        }

        @Override
        public void readComplete() {
        }

        @Override
        public void attemptedBytesRead(int bytes) {
            attemptBytesRead = bytes;
        }

        @Override
        public int attemptedBytesRead() {
            return attemptBytesRead;
        }
    }