import io.netty.handler.codec.http2.DefaultHttp2FrameReader; //导入依赖的package包/类
private Http2ClientConnectionHandler newHttp2ConnectionHandler(Channel ch) {
    final boolean validateHeaders = false;
    final Http2Connection conn = new DefaultHttp2Connection(false);
    conn.addListener(new Http2GoAwayListener(ch));

    Http2FrameReader reader = new DefaultHttp2FrameReader(validateHeaders);
    Http2FrameWriter writer = new DefaultHttp2FrameWriter();

    Http2ConnectionEncoder encoder = new DefaultHttp2ConnectionEncoder(conn, writer);
    Http2ConnectionDecoder decoder = new DefaultHttp2ConnectionDecoder(conn, encoder, reader);

    final Http2Settings http2Settings = http2Settings();

    final Http2ResponseDecoder listener = new Http2ResponseDecoder(conn, ch, encoder);
    final Http2ClientConnectionHandler handler =
            new Http2ClientConnectionHandler(decoder, encoder, http2Settings, listener);
    // Setup post build options
    handler.gracefulShutdownTimeoutMillis(clientFactory.idleTimeoutMillis());

    return handler;
}
 

import io.netty.handler.codec.http2.DefaultHttp2FrameReader; //导入依赖的package包/类
private Http2ConnectionHandler newHttp2ConnectionHandler(ChannelPipeline pipeline) {

        final Http2Connection conn = new DefaultHttp2Connection(true);
        conn.addListener(new Http2GoAwayListener(pipeline.channel()));

        Http2FrameReader reader = new DefaultHttp2FrameReader(true);
        Http2FrameWriter writer = new DefaultHttp2FrameWriter();

        Http2ConnectionEncoder encoder = new DefaultHttp2ConnectionEncoder(conn, writer);
        Http2ConnectionDecoder decoder = new DefaultHttp2ConnectionDecoder(conn, encoder, reader);

        final Http2ConnectionHandler handler =
                new Http2ServerConnectionHandler(decoder, encoder, new Http2Settings());

        // Setup post build options
        final Http2RequestDecoder listener =
                new Http2RequestDecoder(config, pipeline.channel(), handler.encoder());

        handler.connection().addListener(listener);
        handler.decoder().frameListener(listener);
        handler.gracefulShutdownTimeoutMillis(config.idleTimeoutMillis());

        return handler;
    }
 

import io.netty.handler.codec.http2.DefaultHttp2FrameReader; //导入依赖的package包/类
static NettyClientHandler newHandler(
    ClientTransportLifecycleManager lifecycleManager,
    @Nullable KeepAliveManager keepAliveManager,
    int flowControlWindow,
    int maxHeaderListSize,
    Supplier<Stopwatch> stopwatchFactory,
    Runnable tooManyPingsRunnable,
    TransportTracer transportTracer) {
  Preconditions.checkArgument(maxHeaderListSize > 0, "maxHeaderListSize must be positive");
  Http2HeadersDecoder headersDecoder = new GrpcHttp2ClientHeadersDecoder(maxHeaderListSize);
  Http2FrameReader frameReader = new DefaultHttp2FrameReader(headersDecoder);
  Http2FrameWriter frameWriter = new DefaultHttp2FrameWriter();
  Http2Connection connection = new DefaultHttp2Connection(false);
  WeightedFairQueueByteDistributor dist = new WeightedFairQueueByteDistributor(connection);
  dist.allocationQuantum(16 * 1024); // Make benchmarks fast again.
  DefaultHttp2RemoteFlowController controller =
      new DefaultHttp2RemoteFlowController(connection, dist);
  connection.remote().flowController(controller);

  return newHandler(
      connection,
      frameReader,
      frameWriter,
      lifecycleManager,
      keepAliveManager,
      flowControlWindow,
      maxHeaderListSize,
      stopwatchFactory,
      tooManyPingsRunnable,
      transportTracer);
}
 

import io.netty.handler.codec.http2.DefaultHttp2FrameReader; //导入依赖的package包/类
/**
 * Must be called by subclasses to initialize the handler and channel.
 */
protected final void initChannel(Http2HeadersDecoder headersDecoder) throws Exception {
  content = Unpooled.copiedBuffer("hello world", UTF_8);
  frameWriter = mock(Http2FrameWriter.class, delegatesTo(new DefaultHttp2FrameWriter()));
  frameReader = new DefaultHttp2FrameReader(headersDecoder);

  channel = new FakeClockSupportedChanel();
  handler = newHandler();
  channel.pipeline().addLast(handler);
  ctx = channel.pipeline().context(handler);

  writeQueue = initWriteQueue();
}
 

import io.netty.handler.codec.http2.DefaultHttp2FrameReader; //导入依赖的package包/类
private static Http2FrameReader frameReader() {
  return new Http2InboundFrameLogger(new DefaultHttp2FrameReader(),
      FRAME_LOGGER);
}
 

import io.netty.handler.codec.http2.DefaultHttp2FrameReader; //导入依赖的package包/类
private static Http2FrameReader frameReader() {
    return new Http2InboundFrameLogger(new DefaultHttp2FrameReader(), logger);
}
 

import io.netty.handler.codec.http2.DefaultHttp2FrameReader; //导入依赖的package包/类
public HelloWorldHttp2Handler() {
    this(new DefaultHttp2Connection(true), new Http2InboundFrameLogger(
            new DefaultHttp2FrameReader(), logger), 
            new Http2OutboundFrameLogger(new DefaultHttp2FrameWriter(), logger), 
            new SimpleHttp2FrameListener());
}
 

import io.netty.handler.codec.http2.DefaultHttp2FrameReader; //导入依赖的package包/类
private Http2FrameReader frameReader() {
    return new Http2InboundFrameLogger(new DefaultHttp2FrameReader(), logger);
}
 

import io.netty.handler.codec.http2.DefaultHttp2FrameReader; //导入依赖的package包/类
@Test
public void maxFrameSize() throws Exception {

    try (ServerSocket ss = new ServerSocket(0)) {
        final int port = ss.getLocalPort();

        final ClientFactory clientFactory = new ClientFactoryBuilder()
                .useHttp2Preface(true)
                .http2MaxFrameSize(DEFAULT_MAX_FRAME_SIZE * 2) // == 16384 * 2
                .build();

        final HttpClient client = HttpClient.of(clientFactory, "http://127.0.0.1:" + port);
        final CompletableFuture<AggregatedHttpMessage> future = client.get("/").aggregate();

        try (Socket s = ss.accept()) {
            final InputStream in = s.getInputStream();
            final BufferedOutputStream bos = new BufferedOutputStream(s.getOutputStream());

            readBytes(in, connectionPrefaceBuf().capacity()); // Read the connection preface and discard it.

            // Read a SETTINGS frame and validate it.
            assertSettingsFrameOfMaxFrameSize(in);

            sendEmptySettingsAndAckFrame(bos);

            readBytes(in, 9); // Read a SETTINGS_ACK frame and discard it.
            readHeadersFrame(in); // Read a HEADERS frame and discard it.

            sendHeaderFrame(bos);

            ////////////////////////////////////////
            // Transmission of data gets started. //
            ////////////////////////////////////////

            // Send a DATA frame that indicates sending data as much as 0x8000 for stream id 03.
            bos.write(new byte[] { 0x00, (byte) 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03 });
            bos.write(EMPTY_DATA);
            bos.write(EMPTY_DATA);
            bos.flush();

            readBytes(in, 13); // Read a WINDOW_UPDATE frame for connection and discard it.
            readBytes(in, 13); // Read a WINDOW_UPDATE frame for stream id 03 and discard it.

            // Send a DATA frame that exceed MAX_FRAME_SIZE by 1.
            bos.write(new byte[] { 0x00, (byte) 0x80, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03 });
            bos.flush(); // Triggers the client to send a GOAWAY frame for the connection.

            // The client send a GOAWAY frame and the server read it.
            final ByteBuf buffer = readGoAwayFrame(in);
            final DefaultHttp2FrameReader frameReader = new DefaultHttp2FrameReader();

            final CountDownLatch latch = new CountDownLatch(1);
            frameReader.readFrame(null, buffer, new Http2EventAdapter() {
                @Override
                public void onGoAwayRead(ChannelHandlerContext ctx, int lastStreamId, long errorCode,
                                         ByteBuf debugData)
                        throws Http2Exception {
                    assertThat(lastStreamId).isZero(); // 0: connection error
                    assertThat(errorCode).isEqualTo(Http2Error.FRAME_SIZE_ERROR.code());
                    latch.countDown();
                }
            });
            latch.await();
            buffer.release();
        }
    }
}
 

import io.netty.handler.codec.http2.DefaultHttp2FrameReader; //导入依赖的package包/类
static NettyServerHandler newHandler(
    ServerTransportListener transportListener,
    ChannelPromise channelUnused,
    List<ServerStreamTracer.Factory> streamTracerFactories,
    TransportTracer transportTracer,
    int maxStreams,
    int flowControlWindow,
    int maxHeaderListSize,
    int maxMessageSize,
    long keepAliveTimeInNanos,
    long keepAliveTimeoutInNanos,
    long maxConnectionIdleInNanos,
    long maxConnectionAgeInNanos,
    long maxConnectionAgeGraceInNanos,
    boolean permitKeepAliveWithoutCalls,
    long permitKeepAliveTimeInNanos) {
  Preconditions.checkArgument(maxHeaderListSize > 0, "maxHeaderListSize must be positive");
  Http2FrameLogger frameLogger = new Http2FrameLogger(LogLevel.DEBUG, NettyServerHandler.class);
  Http2HeadersDecoder headersDecoder = new GrpcHttp2ServerHeadersDecoder(maxHeaderListSize);
  Http2FrameReader frameReader = new Http2InboundFrameLogger(
      new DefaultHttp2FrameReader(headersDecoder), frameLogger);
  Http2FrameWriter frameWriter =
      new Http2OutboundFrameLogger(new DefaultHttp2FrameWriter(), frameLogger);
  return newHandler(
      channelUnused,
      frameReader,
      frameWriter,
      transportListener,
      streamTracerFactories,
      transportTracer,
      maxStreams,
      flowControlWindow,
      maxHeaderListSize,
      maxMessageSize,
      keepAliveTimeInNanos,
      keepAliveTimeoutInNanos,
      maxConnectionIdleInNanos,
      maxConnectionAgeInNanos,
      maxConnectionAgeGraceInNanos,
      permitKeepAliveWithoutCalls,
      permitKeepAliveTimeInNanos);
}