TestChannelInitializer Class — netty Architecture

Source Code

codec-http2/src/test/java/io/netty/handler/codec/http2/TestChannelInitializer.java lines 34–122

@Sharable
public class TestChannelInitializer extends ChannelInitializer<Channel> {
    ChannelHandler handler;
    AtomicInteger maxReads;

    @Override
    public void initChannel(Channel channel) {
        if (handler != null) {
            channel.pipeline().addLast(handler);
            handler = null;
        }
        if (maxReads != null) {
            channel.config().setRecvByteBufAllocator(new TestNumReadsRecvByteBufAllocator(maxReads));
        }
    }

    /**
     * Designed to read a single byte at a time to control the number of reads done at a fine granularity.
     */
    static final class TestNumReadsRecvByteBufAllocator implements RecvByteBufAllocator {
        private final AtomicInteger numReads;
        private TestNumReadsRecvByteBufAllocator(AtomicInteger numReads) {
            this.numReads = numReads;
        }

        @Override
        public ExtendedHandle newHandle() {
            return new ExtendedHandle() {
                private int attemptedBytesRead;
                private int lastBytesRead;
                private int numMessagesRead;
                @Override
                public ByteBuf allocate(ByteBufAllocator alloc) {
                    return alloc.ioBuffer(guess(), guess());
                }

                @Override
                public int guess() {
                    return 1; // only ever allocate buffers of size 1 to ensure the number of reads is controlled.
                }

                @Override
                public void reset(ChannelConfig config) {
                    numMessagesRead = 0;
                }

                @Override
                public void incMessagesRead(int numMessages) {
                    numMessagesRead += numMessages;
                }

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

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

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

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

                @Override
                public boolean continueReading() {
                    return numMessagesRead < numReads.get();
                }

                @Override
                public boolean continueReading(UncheckedBooleanSupplier maybeMoreDataSupplier) {
                    return continueReading();
                }