Refactoring HTTP/2 Flow Control interfaces.

Motivation:

The terminology used with inbound/outbound is a little confusing since
it's not discussed in the spec. We should switch to using local/remote
instead. Also there is some asymmetry between the inbound/outbound
interfaces which could probably be cleaned up.

Modifications:

Changing the interface names and making a common Http2FlowController
interface for most of the methods.

Result:

The HTTP/2 flow control interfaces should be more clear.

codec-http2/src/main/java/io/netty/handler/codec/http2/DefaultHttp2Connection.java

@@ -53,8 +53,8 @@ public class DefaultHttp2Connection implements Http2Connection {
     private final IntObjectMap<Http2Stream> streamMap = new IntObjectHashMap<Http2Stream>();
     private final ConnectionStream connectionStream = new ConnectionStream();
     private final Set<Http2Stream> activeStreams = new LinkedHashSet<Http2Stream>();
-    private final DefaultEndpoint localEndpoint;
+    private final DefaultEndpoint<Http2LocalFlowController> localEndpoint;
-    private final DefaultEndpoint remoteEndpoint;
+    private final DefaultEndpoint<Http2RemoteFlowController> remoteEndpoint;
     private final Http2StreamRemovalPolicy removalPolicy;
 
     /**
@@ -78,8 +78,8 @@ public class DefaultHttp2Connection implements Http2Connection {
     public DefaultHttp2Connection(boolean server, Http2StreamRemovalPolicy removalPolicy) {
 
         this.removalPolicy = checkNotNull(removalPolicy, "removalPolicy");
-        localEndpoint = new DefaultEndpoint(server);
+        localEndpoint = new DefaultEndpoint<Http2LocalFlowController>(server);
-        remoteEndpoint = new DefaultEndpoint(!server);
+        remoteEndpoint = new DefaultEndpoint<Http2RemoteFlowController>(!server);
 
         // Tell the removal policy how to remove a stream from this connection.
         removalPolicy.setAction(new Action() {
@@ -138,12 +138,12 @@ public class DefaultHttp2Connection implements Http2Connection {
     }
 
     @Override
-    public Endpoint local() {
+    public Endpoint<Http2LocalFlowController> local() {
         return localEndpoint;
     }
 
     @Override
-    public Endpoint remote() {
+    public Endpoint<Http2RemoteFlowController> remote() {
         return remoteEndpoint;
     }
 
@@ -219,9 +219,6 @@ public class DefaultHttp2Connection implements Http2Connection {
         private boolean resetReceived;
         private boolean endOfStreamSent;
         private boolean endOfStreamReceived;
-        private Http2FlowState inboundFlow;
-        private Http2FlowState outboundFlow;
-        private Http2FlowControlWindowManager garbageCollector;
         private PropertyMap data;
 
         DefaultStream(int id) {
@@ -303,36 +300,6 @@ public class DefaultHttp2Connection implements Http2Connection {
             return data.remove(key);
         }
 
-        @Override
-        public Http2FlowState inboundFlow() {
-            return inboundFlow;
-        }
-
-        @Override
-        public void inboundFlow(Http2FlowState state) {
-            inboundFlow = state;
-        }
-
-        @Override
-        public Http2FlowState outboundFlow() {
-            return outboundFlow;
-        }
-
-        @Override
-        public void outboundFlow(Http2FlowState state) {
-            outboundFlow = state;
-        }
-
-        @Override
-        public Http2FlowControlWindowManager garbageCollector() {
-            return garbageCollector;
-        }
-
-        @Override
-        public void garbageCollector(Http2FlowControlWindowManager collector) {
-            garbageCollector = collector;
-        }
-
         @Override
         public final boolean isRoot() {
             return parent == null;
@@ -511,7 +478,7 @@ public class DefaultHttp2Connection implements Http2Connection {
             return state == HALF_CLOSED_REMOTE || state == OPEN || state == RESERVED_LOCAL;
         }
 
-        final DefaultEndpoint createdBy() {
+        final DefaultEndpoint<? extends Http2FlowController> createdBy() {
             return localEndpoint.createdStreamId(id) ? localEndpoint : remoteEndpoint;
         }
 
@@ -742,12 +709,13 @@ public class DefaultHttp2Connection implements Http2Connection {
     /**
      * Simple endpoint implementation.
      */
-    private final class DefaultEndpoint implements Endpoint {
+    private final class DefaultEndpoint<F extends Http2FlowController> implements Endpoint<F> {
         private final boolean server;
         private int nextStreamId;
         private int lastStreamCreated;
         private int lastKnownStream = -1;
         private boolean pushToAllowed = true;
+        private F flowController;
 
         /**
          * The maximum number of active streams allowed to be created by this endpoint.
@@ -911,7 +879,17 @@ public class DefaultHttp2Connection implements Http2Connection {
         }
 
         @Override
-        public Endpoint opposite() {
+        public F flowController() {
+            return flowController;
+        }
+
+        @Override
+        public void flowController(F flowController) {
+            this.flowController = checkNotNull(flowController, "flowController");
+        }
+
+        @Override
+        public Endpoint<? extends Http2FlowController> opposite() {
             return isLocal() ? remoteEndpoint : localEndpoint;
         }
 

codec-http2/src/main/java/io/netty/handler/codec/http2/DefaultHttp2ConnectionDecoder.java

@@ -40,7 +40,6 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
     private final Http2LifecycleManager lifecycleManager;
     private final Http2ConnectionEncoder encoder;
     private final Http2FrameReader frameReader;
-    private final Http2InboundFlowController inboundFlow;
     private final Http2FrameListener listener;
     private boolean prefaceReceived;
 
@@ -52,7 +51,6 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
         private Http2LifecycleManager lifecycleManager;
         private Http2ConnectionEncoder encoder;
         private Http2FrameReader frameReader;
-        private Http2InboundFlowController inboundFlow;
         private Http2FrameListener listener;
 
         @Override
@@ -72,12 +70,6 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
             return lifecycleManager;
         }
 
-        @Override
-        public Builder inboundFlow(Http2InboundFlowController inboundFlow) {
-            this.inboundFlow = inboundFlow;
-            return this;
-        }
-
         @Override
         public Builder frameReader(Http2FrameReader frameReader) {
             this.frameReader = frameReader;
@@ -111,8 +103,11 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
         frameReader = checkNotNull(builder.frameReader, "frameReader");
         lifecycleManager = checkNotNull(builder.lifecycleManager, "lifecycleManager");
         encoder = checkNotNull(builder.encoder, "encoder");
-        inboundFlow = checkNotNull(builder.inboundFlow, "inboundFlow");
         listener = checkNotNull(builder.listener, "listener");
+        if (connection.local().flowController() == null) {
+            connection.local().flowController(
+                    new DefaultHttp2LocalFlowController(connection, encoder.frameWriter()));
+        }
     }
 
     @Override
@@ -120,6 +115,11 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
         return connection;
     }
 
+    @Override
+    public final Http2LocalFlowController flowController() {
+        return connection.local().flowController();
+    }
+
     @Override
     public Http2FrameListener listener() {
         return listener;
@@ -141,7 +141,7 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
         Http2FrameReader.Configuration config = frameReader.configuration();
         Http2HeaderTable headerTable = config.headerTable();
         Http2FrameSizePolicy frameSizePolicy = config.frameSizePolicy();
-        settings.initialWindowSize(inboundFlow.initialWindowSize());
+        settings.initialWindowSize(flowController().initialWindowSize());
         settings.maxConcurrentStreams(connection.remote().maxStreams());
         settings.headerTableSize(headerTable.maxHeaderTableSize());
         settings.maxFrameSize(frameSizePolicy.maxFrameSize());
@@ -189,7 +189,7 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
 
         Integer initialWindowSize = settings.initialWindowSize();
         if (initialWindowSize != null) {
-            inboundFlow.initialWindowSize(initialWindowSize);
+            flowController().initialWindowSize(initialWindowSize);
         }
     }
 
@@ -198,8 +198,8 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
         frameReader.close();
     }
 
-    private static int unprocessedBytes(Http2Stream stream) {
+    private int unconsumedBytes(Http2Stream stream) {
-        return stream.garbageCollector().unProcessedBytes();
+        return flowController().unconsumedBytes(stream);
     }
 
     /**
@@ -248,13 +248,14 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
             }
 
             int bytesToReturn = data.readableBytes() + padding;
-            int unprocessedBytes = unprocessedBytes(stream);
+            int unconsumedBytes = unconsumedBytes(stream);
+            Http2LocalFlowController flowController = flowController();
             try {
                 // If we should apply flow control, do so now.
                 if (shouldApplyFlowControl) {
-                    inboundFlow.applyFlowControl(ctx, streamId, data, padding, endOfStream);
+                    flowController.receiveFlowControlledFrame(ctx, stream, data, padding, endOfStream);
-                    // Update the unprocessed bytes after flow control is applied.
+                    // Update the unconsumed bytes after flow control is applied.
-                    unprocessedBytes = unprocessedBytes(stream);
+                    unconsumedBytes = unconsumedBytes(stream);
                 }
 
                 // If we should ignore this frame, do so now.
@@ -275,20 +276,20 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
                 // If an exception happened during delivery, the listener may have returned part
                 // of the bytes before the error occurred. If that's the case, subtract that from
                 // the total processed bytes so that we don't return too many bytes.
-                int delta = unprocessedBytes - unprocessedBytes(stream);
+                int delta = unconsumedBytes - unconsumedBytes(stream);
                 bytesToReturn -= delta;
                 throw e;
             } catch (RuntimeException e) {
                 // If an exception happened during delivery, the listener may have returned part
                 // of the bytes before the error occurred. If that's the case, subtract that from
                 // the total processed bytes so that we don't return too many bytes.
-                int delta = unprocessedBytes - unprocessedBytes(stream);
+                int delta = unconsumedBytes - unconsumedBytes(stream);
                 bytesToReturn -= delta;
                 throw e;
             } finally {
                 // If appropriate, returned the processed bytes to the flow controller.
                 if (shouldApplyFlowControl && bytesToReturn > 0) {
-                    stream.garbageCollector().returnProcessedBytes(ctx, bytesToReturn);
+                    flowController.consumeBytes(ctx, stream, bytesToReturn);
                 }
 
                 if (endOfStream) {
@@ -452,7 +453,7 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
 
             Integer initialWindowSize = settings.initialWindowSize();
             if (initialWindowSize != null) {
-                inboundFlow.initialWindowSize(initialWindowSize);
+                flowController().initialWindowSize(initialWindowSize);
             }
         }
 
@@ -530,7 +531,7 @@ public class DefaultHttp2ConnectionDecoder implements Http2ConnectionDecoder {
             }
 
             // Update the outbound flow controller.
-            encoder.updateOutboundWindowSize(streamId, windowSizeIncrement);
+            encoder.flowController().incrementWindowSize(ctx, stream, windowSizeIncrement);
 
             listener.onWindowUpdateRead(ctx, streamId, windowSizeIncrement);
         }

codec-http2/src/main/java/io/netty/handler/codec/http2/DefaultHttp2ConnectionEncoder.java

@@ -32,7 +32,6 @@ import java.util.ArrayDeque;
 public class DefaultHttp2ConnectionEncoder implements Http2ConnectionEncoder {
     private final Http2FrameWriter frameWriter;
     private final Http2Connection connection;
-    private final Http2OutboundFlowController outboundFlow;
     private final Http2LifecycleManager lifecycleManager;
     // We prefer ArrayDeque to LinkedList because later will produce more GC.
     // This initial capacity is plenty for SETTINGS traffic.
@@ -44,7 +43,6 @@ public class DefaultHttp2ConnectionEncoder implements Http2ConnectionEncoder {
     public static class Builder implements Http2ConnectionEncoder.Builder {
         protected Http2FrameWriter frameWriter;
         protected Http2Connection connection;
-        protected Http2OutboundFlowController outboundFlow;
         protected Http2LifecycleManager lifecycleManager;
 
         @Override
@@ -73,13 +71,6 @@ public class DefaultHttp2ConnectionEncoder implements Http2ConnectionEncoder {
             return this;
         }
 
-        @Override
-        public Builder outboundFlow(
-                Http2OutboundFlowController outboundFlow) {
-            this.outboundFlow = outboundFlow;
-            return this;
-        }
-
         @Override
         public Http2ConnectionEncoder build() {
             return new DefaultHttp2ConnectionEncoder(this);
@@ -91,10 +82,12 @@ public class DefaultHttp2ConnectionEncoder implements Http2ConnectionEncoder {
     }
 
     protected DefaultHttp2ConnectionEncoder(Builder builder) {
-        frameWriter = checkNotNull(builder.frameWriter, "frameWriter");
         connection = checkNotNull(builder.connection, "connection");
-        outboundFlow = checkNotNull(builder.outboundFlow, "outboundFlow");
+        frameWriter = checkNotNull(builder.frameWriter, "frameWriter");
         lifecycleManager = checkNotNull(builder.lifecycleManager, "lifecycleManager");
+        if (connection.remote().flowController() == null) {
+            connection.remote().flowController(new DefaultHttp2RemoteFlowController(connection, frameWriter));
+        }
     }
 
     @Override
@@ -107,6 +100,11 @@ public class DefaultHttp2ConnectionEncoder implements Http2ConnectionEncoder {
         return connection;
     }
 
+    @Override
+    public final Http2RemoteFlowController flowController() {
+        return connection().remote().flowController();
+    }
+
     @Override
     public void remoteSettings(Http2Settings settings) throws Http2Exception {
         Boolean pushEnabled = settings.pushEnabled();
@@ -142,19 +140,20 @@ public class DefaultHttp2ConnectionEncoder implements Http2ConnectionEncoder {
 
         Integer initialWindowSize = settings.initialWindowSize();
         if (initialWindowSize != null) {
-            initialOutboundWindowSize(initialWindowSize);
+            flowController().initialWindowSize(initialWindowSize);
         }
     }
 
     @Override
     public ChannelFuture writeData(final ChannelHandlerContext ctx, final int streamId, ByteBuf data, int padding,
             final boolean endOfStream, ChannelPromise promise) {
+        Http2Stream stream;
         try {
             if (connection.isGoAway()) {
                 throw new IllegalStateException("Sending data after connection going away.");
             }
 
-            Http2Stream stream = connection.requireStream(streamId);
+            stream = connection.requireStream(streamId);
             if (stream.isResetSent()) {
                 throw new IllegalStateException("Sending data after sending RST_STREAM.");
             }
@@ -184,7 +183,7 @@ public class DefaultHttp2ConnectionEncoder implements Http2ConnectionEncoder {
 
         // Hand control of the frame to the flow controller.
         ChannelFuture future =
-                outboundFlow.writeData(ctx, streamId, data, padding, endOfStream, promise);
+                flowController().sendFlowControlledFrame(ctx, stream, data, padding, endOfStream, promise);
         future.addListener(new ChannelFutureListener() {
             @Override
             public void operationComplete(ChannelFuture future) throws Exception {
@@ -202,11 +201,6 @@ public class DefaultHttp2ConnectionEncoder implements Http2ConnectionEncoder {
         return future;
     }
 
-    @Override
-    public ChannelFuture lastWriteForStream(int streamId) {
-        return outboundFlow.lastWriteForStream(streamId);
-    }
-
     @Override
     public ChannelFuture writeHeaders(ChannelHandlerContext ctx, int streamId, Http2Headers headers, int padding,
             boolean endStream, ChannelPromise promise) {
@@ -219,7 +213,7 @@ public class DefaultHttp2ConnectionEncoder implements Http2ConnectionEncoder {
             final boolean exclusive, final int padding, final boolean endOfStream,
             final ChannelPromise promise) {
         Http2Stream stream = connection.stream(streamId);
-        ChannelFuture lastDataWrite = lastWriteForStream(streamId);
+        ChannelFuture lastDataWrite = stream != null ? flowController().lastFlowControlledFrameSent(stream) : null;
         try {
             if (connection.isGoAway()) {
                 throw connectionError(PROTOCOL_ERROR, "Sending headers after connection going away.");
@@ -472,19 +466,4 @@ public class DefaultHttp2ConnectionEncoder implements Http2ConnectionEncoder {
     public Configuration configuration() {
         return frameWriter.configuration();
     }
-
-    @Override
-    public void initialOutboundWindowSize(int newWindowSize) throws Http2Exception {
-        outboundFlow.initialOutboundWindowSize(newWindowSize);
-    }
-
-    @Override
-    public int initialOutboundWindowSize() {
-        return outboundFlow.initialOutboundWindowSize();
-    }
-
-    @Override
-    public void updateOutboundWindowSize(int streamId, int deltaWindowSize) throws Http2Exception {
-        outboundFlow.updateOutboundWindowSize(streamId, deltaWindowSize);
-    }
 }

codec-http2/src/main/java/io/netty/handler/codec/http2/DefaultHttp2LocalFlowController.java

@@ -21,7 +21,6 @@ import static io.netty.handler.codec.http2.Http2CodecUtil.MAX_INITIAL_WINDOW_SIZ
 import static io.netty.handler.codec.http2.Http2CodecUtil.MIN_INITIAL_WINDOW_SIZE;
 import static io.netty.handler.codec.http2.Http2Error.FLOW_CONTROL_ERROR;
 import static io.netty.handler.codec.http2.Http2Error.INTERNAL_ERROR;
-import static io.netty.handler.codec.http2.Http2Error.PROTOCOL_ERROR;
 import static io.netty.handler.codec.http2.Http2Exception.connectionError;
 import static io.netty.handler.codec.http2.Http2Exception.streamError;
 import static io.netty.util.internal.ObjectUtil.checkNotNull;
@@ -33,9 +32,9 @@ import io.netty.handler.codec.http2.Http2Exception.CompositeStreamException;
 import io.netty.handler.codec.http2.Http2Exception.StreamException;
 
 /**
- * Basic implementation of {@link Http2InboundFlowController}.
+ * Basic implementation of {@link Http2LocalFlowController}.
  */
-public class DefaultHttp2InboundFlowController implements Http2InboundFlowController {
+public class DefaultHttp2LocalFlowController implements Http2LocalFlowController {
     private static final int DEFAULT_COMPOSITE_EXCEPTION_SIZE = 4;
     /**
      * The default ratio of window size to initial window size below which a {@code WINDOW_UPDATE}
@@ -48,11 +47,11 @@ public class DefaultHttp2InboundFlowController implements Http2InboundFlowContro
     private volatile float windowUpdateRatio;
     private volatile int initialWindowSize = DEFAULT_WINDOW_SIZE;
 
-    public DefaultHttp2InboundFlowController(Http2Connection connection, Http2FrameWriter frameWriter) {
+    public DefaultHttp2LocalFlowController(Http2Connection connection, Http2FrameWriter frameWriter) {
         this(connection, frameWriter, DEFAULT_WINDOW_UPDATE_RATIO);
     }
 
-    public DefaultHttp2InboundFlowController(Http2Connection connection,
+    public DefaultHttp2LocalFlowController(Http2Connection connection,
             Http2FrameWriter frameWriter, float windowUpdateRatio) {
         this.connection = checkNotNull(connection, "connection");
         this.frameWriter = checkNotNull(frameWriter, "frameWriter");
@@ -60,17 +59,13 @@ public class DefaultHttp2InboundFlowController implements Http2InboundFlowContro
 
         // Add a flow state for the connection.
         final Http2Stream connectionStream = connection.connectionStream();
-        final FlowState connectionFlowState = new FlowState(connectionStream);
+        connectionStream.setProperty(FlowState.class, new FlowState(connectionStream));
-        connectionStream.inboundFlow(connectionFlowState);
-        connectionStream.garbageCollector(connectionFlowState);
 
         // Register for notification of new streams.
         connection.addListener(new Http2ConnectionAdapter() {
             @Override
             public void streamAdded(Http2Stream stream) {
-                final FlowState flowState = new FlowState(stream);
+                stream.setProperty(FlowState.class, new FlowState(stream));
-                stream.inboundFlow(flowState);
-                stream.garbageCollector(flowState);
             }
         });
     }
@@ -99,27 +94,35 @@ public class DefaultHttp2InboundFlowController implements Http2InboundFlowContro
         }
     }
 
-    @Override
-    public void initialStreamWindowSize(ChannelHandlerContext ctx, int streamId, int newWindowSize)
-            throws Http2Exception {
-        checkNotNull(ctx, "ctx");
-        if (newWindowSize < MIN_INITIAL_WINDOW_SIZE || newWindowSize > MAX_INITIAL_WINDOW_SIZE) {
-            throw new IllegalArgumentException("Invalid newWindowSize: " + newWindowSize);
-        }
-
-        FlowState state = stateOrFail(streamId);
-        state.initialStreamWindowSize(newWindowSize);
-        state.writeWindowUpdateIfNeeded(ctx);
-    }
-
     @Override
     public int initialWindowSize() {
         return initialWindowSize;
     }
 
     @Override
-    public int initialStreamWindowSize(int streamId) throws Http2Exception {
+    public int windowSize(Http2Stream stream) {
-        return stateOrFail(streamId).initialStreamWindowSize();
+        return state(stream).window();
+    }
+
+    @Override
+    public void incrementWindowSize(ChannelHandlerContext ctx, Http2Stream stream, int delta) throws Http2Exception {
+        checkNotNull(ctx, "ctx");
+        FlowState state = state(stream);
+        // Just add the delta to the stream-specific initial window size so that the next time the window
+        // expands it will grow to the new initial size.
+        state.incrementInitialStreamWindow(delta);
+        state.writeWindowUpdateIfNeeded(ctx);
+    }
+
+    @Override
+    public void consumeBytes(ChannelHandlerContext ctx, Http2Stream stream, int numBytes)
+            throws Http2Exception {
+        state(stream).consumeBytes(ctx, numBytes);
+    }
+
+    @Override
+    public int unconsumedBytes(Http2Stream stream) {
+        return state(stream).unconsumedBytes();
     }
 
     private static void checkValidRatio(float ratio) {
@@ -159,14 +162,13 @@ public class DefaultHttp2InboundFlowController implements Http2InboundFlowContro
      * be considered a {@link Http2Error#PROTOCOL_ERROR} if a {@code WINDOW_UPDATE}
      * was generated by this method before the initial {@code SETTINGS} frame is sent.
      * @param ctx the context to use if a {@code WINDOW_UPDATE} is determined necessary.
-     * @param streamId the stream for which {@code ratio} applies to.
+     * @param stream the stream for which {@code ratio} applies to.
      * @param ratio the ratio to use when checking if a {@code WINDOW_UPDATE} is determined necessary.
      * @throws Http2Exception If a protocol-error occurs while generating {@code WINDOW_UPDATE} frames
      */
-    public void windowUpdateRatio(ChannelHandlerContext ctx, int streamId, float ratio) throws Http2Exception {
+    public void windowUpdateRatio(ChannelHandlerContext ctx, Http2Stream stream, float ratio) throws Http2Exception {
-        checkNotNull(ctx, "ctx");
         checkValidRatio(ratio);
-        FlowState state = stateOrFail(streamId);
+        FlowState state = state(stream);
         state.windowUpdateRatio(ratio);
         state.writeWindowUpdateIfNeeded(ctx);
     }
@@ -177,52 +179,37 @@ public class DefaultHttp2InboundFlowController implements Http2InboundFlowContro
      * be sent. This window update ratio will only be applied to {@code streamId}.
      * @throws Http2Exception If no stream corresponding to {@code stream} could be found.
      */
-    public float windowUpdateRatio(int streamId) throws Http2Exception {
+    public float windowUpdateRatio(Http2Stream stream) throws Http2Exception {
-        return stateOrFail(streamId).windowUpdateRatio();
+        return state(stream).windowUpdateRatio();
     }
 
     @Override
-    public void applyFlowControl(ChannelHandlerContext ctx, int streamId, ByteBuf data,
+    public void receiveFlowControlledFrame(ChannelHandlerContext ctx, Http2Stream stream, ByteBuf data,
             int padding, boolean endOfStream) throws Http2Exception {
         int dataLength = data.readableBytes() + padding;
 
         // Apply the connection-level flow control
-        connectionState().applyFlowControl(dataLength);
+        connectionState().receiveFlowControlledFrame(dataLength);
 
         // Apply the stream-level flow control
-        FlowState state = stateOrFail(streamId);
+        FlowState state = state(stream);
         state.endOfStream(endOfStream);
-        state.applyFlowControl(dataLength);
+        state.receiveFlowControlledFrame(dataLength);
     }
 
     private FlowState connectionState() {
         return state(connection.connectionStream());
     }
 
-    private FlowState state(int streamId) {
-        Http2Stream stream = connection.stream(streamId);
-        return stream != null ? state(stream) : null;
-    }
-
     private FlowState state(Http2Stream stream) {
-        return (FlowState) stream.inboundFlow();
+        checkNotNull(stream, "stream");
-    }
+        return stream.getProperty(FlowState.class);
-
-    /**
-     * Gets the window for the stream or raises a {@code PROTOCOL_ERROR} if not found.
-     */
-    private FlowState stateOrFail(int streamId) throws Http2Exception {
-        FlowState state = state(streamId);
-        if (state == null) {
-            throw connectionError(PROTOCOL_ERROR, "Flow control window missing for stream: %d", streamId);
-        }
-        return state;
     }
 
     /**
      * Flow control window state for an individual stream.
      */
-    private final class FlowState implements Http2FlowState, Http2FlowControlWindowManager {
+    private final class FlowState {
         private final Http2Stream stream;
 
         /**
@@ -260,8 +247,7 @@ public class DefaultHttp2InboundFlowController implements Http2InboundFlowContro
             streamWindowUpdateRatio = windowUpdateRatio;
         }
 
-        @Override
+        int window() {
-        public int window() {
             return window;
         }
 
@@ -277,14 +263,6 @@ public class DefaultHttp2InboundFlowController implements Http2InboundFlowContro
             streamWindowUpdateRatio = ratio;
         }
 
-        int initialStreamWindowSize() {
-            return initialStreamWindowSize;
-        }
-
-        void initialStreamWindowSize(int initialWindowSize) {
-            initialStreamWindowSize = initialWindowSize;
-        }
-
         /**
          * Increment the initial window size for this stream.
          * @param delta The amount to increase the initial window size by.
@@ -319,7 +297,7 @@ public class DefaultHttp2InboundFlowController implements Http2InboundFlowContro
          * @param dataLength The amount of data to for which this stream is no longer eligible to use for flow control.
          * @throws Http2Exception If too much data is used relative to how much is available.
          */
-        void applyFlowControl(int dataLength) throws Http2Exception {
+        void receiveFlowControlledFrame(int dataLength) throws Http2Exception {
             assert dataLength > 0;
 
             // Apply the delta. Even if we throw an exception we want to have taken this delta into account.
@@ -347,12 +325,10 @@ public class DefaultHttp2InboundFlowController implements Http2InboundFlowContro
             processedWindow -= delta;
         }
 
-        @Override
+        void consumeBytes(ChannelHandlerContext ctx, int numBytes) throws Http2Exception {
-        public void returnProcessedBytes(ChannelHandlerContext ctx, int numBytes) throws Http2Exception {
             if (stream.id() == CONNECTION_STREAM_ID) {
                 throw new UnsupportedOperationException("Returning bytes for the connection window is not supported");
             }
-            checkNotNull(ctx, "ctx");
             if (numBytes <= 0) {
                 throw new IllegalArgumentException("numBytes must be positive");
             }
@@ -367,16 +343,10 @@ public class DefaultHttp2InboundFlowController implements Http2InboundFlowContro
             writeWindowUpdateIfNeeded(ctx);
         }
 
-        @Override
+        public int unconsumedBytes() {
-        public int unProcessedBytes() {
             return processedWindow - window;
         }
 
-        @Override
-        public Http2Stream stream() {
-            return stream;
-        }
-
         /**
          * Updates the flow control window for this stream if it is appropriate.
          */

codec-http2/src/main/java/io/netty/handler/codec/http2/DefaultHttp2RemoteFlowController.java

@@ -17,11 +17,9 @@ package io.netty.handler.codec.http2;
 
 import static io.netty.handler.codec.http2.Http2CodecUtil.CONNECTION_STREAM_ID;
 import static io.netty.handler.codec.http2.Http2CodecUtil.DEFAULT_WINDOW_SIZE;
-import static io.netty.handler.codec.http2.Http2Error.PROTOCOL_ERROR;
 import static io.netty.handler.codec.http2.Http2Error.FLOW_CONTROL_ERROR;
 import static io.netty.handler.codec.http2.Http2Error.INTERNAL_ERROR;
 import static io.netty.handler.codec.http2.Http2Exception.streamError;
-import static io.netty.handler.codec.http2.Http2Exception.connectionError;
 import static io.netty.util.internal.ObjectUtil.checkNotNull;
 import static java.lang.Math.max;
 import static java.lang.Math.min;
@@ -38,9 +36,9 @@ import java.util.Queue;
 import java.util.concurrent.atomic.AtomicInteger;
 
 /**
- * Basic implementation of {@link Http2OutboundFlowController}.
+ * Basic implementation of {@link Http2RemoteFlowController}.
  */
-public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowController {
+public class DefaultHttp2RemoteFlowController implements Http2RemoteFlowController {
 
     /**
      * A {@link Comparator} that sorts streams in ascending order the amount of streamable data.
@@ -58,19 +56,19 @@ public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowCont
     private ChannelHandlerContext ctx;
     private boolean frameSent;
 
-    public DefaultHttp2OutboundFlowController(Http2Connection connection, Http2FrameWriter frameWriter) {
+    public DefaultHttp2RemoteFlowController(Http2Connection connection, Http2FrameWriter frameWriter) {
         this.connection = checkNotNull(connection, "connection");
         this.frameWriter = checkNotNull(frameWriter, "frameWriter");
 
         // Add a flow state for the connection.
-        connection.connectionStream().outboundFlow(new OutboundFlowState(connection.connectionStream()));
+        connection.connectionStream().setProperty(FlowState.class, new FlowState(connection.connectionStream()));
 
         // Register for notification of new streams.
         connection.addListener(new Http2ConnectionAdapter() {
             @Override
             public void streamAdded(Http2Stream stream) {
                 // Just add a new flow state to the stream.
-                stream.outboundFlow(new OutboundFlowState(stream));
+                stream.setProperty(FlowState.class, new FlowState(stream));
             }
 
             @Override
@@ -108,7 +106,7 @@ public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowCont
     }
 
     @Override
-    public void initialOutboundWindowSize(int newWindowSize) throws Http2Exception {
+    public void initialWindowSize(int newWindowSize) throws Http2Exception {
         if (newWindowSize < 0) {
             throw new IllegalArgumentException("Invalid initial window size: " + newWindowSize);
         }
@@ -117,8 +115,7 @@ public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowCont
         initialWindowSize = newWindowSize;
         for (Http2Stream stream : connection.activeStreams()) {
             // Verify that the maximum value is not exceeded by this change.
-            OutboundFlowState state = state(stream);
+            state(stream).incrementStreamWindow(delta);
-            state.incrementStreamWindow(delta);
         }
 
         if (delta > 0) {
@@ -128,19 +125,24 @@ public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowCont
     }
 
     @Override
-    public int initialOutboundWindowSize() {
+    public int initialWindowSize() {
         return initialWindowSize;
     }
 
     @Override
-    public void updateOutboundWindowSize(int streamId, int delta) throws Http2Exception {
+    public int windowSize(Http2Stream stream) {
-        if (streamId == CONNECTION_STREAM_ID) {
+        return state(stream).window();
+    }
+
+    @Override
+    public void incrementWindowSize(ChannelHandlerContext ctx, Http2Stream stream, int delta) throws Http2Exception {
+        if (stream.id() == CONNECTION_STREAM_ID) {
             // Update the connection window and write any pending frames for all streams.
             connectionState().incrementStreamWindow(delta);
             writePendingBytes();
         } else {
             // Update the stream window and write any pending frames for the stream.
-            OutboundFlowState state = stateOrFail(streamId);
+            FlowState state = state(stream);
             state.incrementStreamWindow(delta);
             frameSent = false;
             state.writeBytes(state.writableWindow());
@@ -151,8 +153,8 @@ public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowCont
     }
 
     @Override
-    public ChannelFuture writeData(ChannelHandlerContext ctx, int streamId, ByteBuf data, int padding,
+    public ChannelFuture sendFlowControlledFrame(ChannelHandlerContext ctx, Http2Stream stream,
-            boolean endStream, ChannelPromise promise) {
+            ByteBuf data, int padding, boolean endStream, ChannelPromise promise) {
         checkNotNull(ctx, "ctx");
         checkNotNull(promise, "promise");
         checkNotNull(data, "data");
@@ -162,20 +164,17 @@ public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowCont
         if (padding < 0) {
             throw new IllegalArgumentException("padding must be >= 0");
         }
-        if (streamId <= 0) {
-            throw new IllegalArgumentException("streamId must be >= 0");
-        }
 
         // Save the context. We'll use this later when we write pending bytes.
         this.ctx = ctx;
 
         try {
-            OutboundFlowState state = stateOrFail(streamId);
+            FlowState state = state(stream);
 
             int window = state.writableWindow();
             boolean framesAlreadyQueued = state.hasFrame();
 
-            OutboundFlowState.Frame frame = state.newFrame(promise, data, padding, endStream);
+            FlowState.Frame frame = state.newFrame(promise, data, padding, endStream);
             if (!framesAlreadyQueued && window >= frame.size()) {
                 // Window size is large enough to send entire data frame
                 frame.write();
@@ -194,41 +193,33 @@ public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowCont
             // Create and send a partial frame up to the window size.
             frame.split(window).write();
             ctx.flush();
-        } catch (Http2Exception e) {
+        } catch (Throwable e) {
             promise.setFailure(e);
         }
         return promise;
     }
 
     @Override
-    public ChannelFuture lastWriteForStream(int streamId) {
+    public ChannelFuture lastFlowControlledFrameSent(Http2Stream stream) {
-        OutboundFlowState state = state(streamId);
+        FlowState state = state(stream);
         return state != null ? state.lastNewFrame() : null;
     }
 
-    private static OutboundFlowState state(Http2Stream stream) {
-        return (OutboundFlowState) stream.outboundFlow();
-    }
-
-    private OutboundFlowState connectionState() {
-        return state(connection.connectionStream());
-    }
-
-    private OutboundFlowState state(int streamId) {
-        Http2Stream stream = connection.stream(streamId);
-        return stream != null ? state(stream) : null;
-    }
-
     /**
-     * Attempts to get the {@link OutboundFlowState} for the given stream. If not available, raises a
+     * For testing purposes only. Exposes the number of streamable bytes for the tree rooted at
-     * {@code PROTOCOL_ERROR}.
+     * the given stream.
      */
-    private OutboundFlowState stateOrFail(int streamId) throws Http2Exception {
+    int streamableBytesForTree(Http2Stream stream) {
-        OutboundFlowState state = state(streamId);
+        return state(stream).streamableBytesForTree();
-        if (state == null) {
-            throw connectionError(PROTOCOL_ERROR, "Missing flow control window for stream: %d", streamId);
     }
-        return state;
+
+    private static FlowState state(Http2Stream stream) {
+        checkNotNull(stream, "stream");
+        return stream.getProperty(FlowState.class);
+    }
+
+    private FlowState connectionState() {
+        return state(connection.connectionStream());
     }
 
     /**
@@ -273,7 +264,7 @@ public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowCont
      * @return An object summarizing the write and allocation results.
      */
     private int writeChildren(Http2Stream parent, int connectionWindow) {
-        OutboundFlowState state = state(parent);
+        FlowState state = state(parent);
         if (state.streamableBytesForTree() <= 0) {
             return 0;
         }
@@ -353,7 +344,7 @@ public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowCont
     /**
      * Write bytes allocated to {@code state}
      */
-    private static void writeChildNode(OutboundFlowState state) {
+    private static void writeChildNode(FlowState state) {
         state.writeBytes(state.allocated());
         state.resetAllocated();
     }
@@ -361,7 +352,7 @@ public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowCont
     /**
      * The outbound flow control state for a single stream.
      */
-    final class OutboundFlowState implements Http2FlowState {
+    final class FlowState {
         private final Queue<Frame> pendingWriteQueue;
         private final Http2Stream stream;
         private int window = initialWindowSize;
@@ -370,12 +361,11 @@ public class DefaultHttp2OutboundFlowController implements Http2OutboundFlowCont
         private int allocated;
         private ChannelFuture lastNewFrame;
 
-        private OutboundFlowState(Http2Stream stream) {
+        private FlowState(Http2Stream stream) {
             this.stream = stream;
             pendingWriteQueue = new ArrayDeque<Frame>(2);
         }
 
-        @Override
         public int window() {
             return window;
         }

codec-http2/src/main/java/io/netty/handler/codec/http2/DelegatingDecompressorFrameListener.java

@@ -14,7 +14,6 @@
  */
 package io.netty.handler.codec.http2;
 
-import static io.netty.handler.codec.http2.Http2Error.INTERNAL_ERROR;
 import static io.netty.handler.codec.http.HttpHeaderNames.CONTENT_ENCODING;
 import static io.netty.handler.codec.http.HttpHeaderNames.CONTENT_LENGTH;
 import static io.netty.handler.codec.http.HttpHeaderValues.DEFLATE;
@@ -22,7 +21,9 @@ import static io.netty.handler.codec.http.HttpHeaderValues.GZIP;
 import static io.netty.handler.codec.http.HttpHeaderValues.IDENTITY;
 import static io.netty.handler.codec.http.HttpHeaderValues.X_DEFLATE;
 import static io.netty.handler.codec.http.HttpHeaderValues.X_GZIP;
+import static io.netty.handler.codec.http2.Http2Error.INTERNAL_ERROR;
 import static io.netty.handler.codec.http2.Http2Exception.streamError;
+import static io.netty.util.internal.ObjectUtil.checkNotNull;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.ChannelHandlerContext;
@@ -40,7 +41,7 @@ public class DelegatingDecompressorFrameListener extends Http2FrameListenerDecor
     private static final Http2ConnectionAdapter CLEAN_UP_LISTENER = new Http2ConnectionAdapter() {
         @Override
         public void streamRemoved(Http2Stream stream) {
-            final Http2Decompressor decompressor = stream.getProperty(Http2Decompressor.class);
+            final Http2Decompressor decompressor = decompressor(stream);
             if (decompressor != null) {
                 cleanup(stream, decompressor);
             }
@@ -49,6 +50,7 @@ public class DelegatingDecompressorFrameListener extends Http2FrameListenerDecor
 
     private final Http2Connection connection;
     private final boolean strict;
+    private boolean flowControllerInitialized;
 
     public DelegatingDecompressorFrameListener(Http2Connection connection, Http2FrameListener listener) {
         this(connection, listener, true);
@@ -67,8 +69,7 @@ public class DelegatingDecompressorFrameListener extends Http2FrameListenerDecor
     public int onDataRead(ChannelHandlerContext ctx, int streamId, ByteBuf data, int padding, boolean endOfStream)
             throws Http2Exception {
         final Http2Stream stream = connection.stream(streamId);
-        final Http2Decompressor decompressor = stream == null ? null :
+        final Http2Decompressor decompressor = decompressor(stream);
-            (Http2Decompressor) stream.getProperty(Http2Decompressor.class);
         if (decompressor == null) {
             // The decompressor may be null if no compatible encoding type was found in this stream's headers
             return listener.onDataRead(ctx, streamId, data, padding, endOfStream);
@@ -203,7 +204,7 @@ public class DelegatingDecompressorFrameListener extends Http2FrameListenerDecor
             return;
         }
 
-        Http2Decompressor decompressor = stream.getProperty(Http2Decompressor.class);
+        Http2Decompressor decompressor = decompressor(stream);
         if (decompressor == null && !endOfStream) {
             // Determine the content encoding.
             AsciiString contentEncoding = headers.get(CONTENT_ENCODING);
@@ -214,7 +215,6 @@ public class DelegatingDecompressorFrameListener extends Http2FrameListenerDecor
             if (channel != null) {
                 decompressor = new Http2Decompressor(channel);
                 stream.setProperty(Http2Decompressor.class, decompressor);
-                stream.garbageCollector(new DecompressorGarbageCollector(stream.garbageCollector()));
                 // Decode the content and remove or replace the existing headers
                 // so that the message looks like a decoded message.
                 AsciiString targetContentEncoding = getTargetContentEncoding(contentEncoding);
@@ -231,8 +231,19 @@ public class DelegatingDecompressorFrameListener extends Http2FrameListenerDecor
             // this content-length will not be correct. Instead of queuing messages or delaying sending
             // header frames...just remove the content-length header
             headers.remove(CONTENT_LENGTH);
+
+            // The first time that we initialize a decompressor, decorate the local flow controller to
+            // properly convert consumed bytes.
+            if (!flowControllerInitialized) {
+                flowControllerInitialized = true;
+                connection.local().flowController(new ConsumedBytesConverter(connection.local().flowController()));
             }
         }
+    }
+
+    private static Http2Decompressor decompressor(Http2Stream stream) {
+        return (Http2Decompressor) (stream == null? null : stream.getProperty(Http2Decompressor.class));
+    }
 
     /**
      * Release remaining content from the {@link EmbeddedChannel} and remove the decompressor
@@ -253,10 +264,6 @@ public class DelegatingDecompressorFrameListener extends Http2FrameListenerDecor
             }
         }
         decompressor = stream.removeProperty(Http2Decompressor.class);
-        if (decompressor != null) {
-            DecompressorGarbageCollector gc = (DecompressorGarbageCollector) stream.garbageCollector();
-            stream.garbageCollector(gc.original());
-        }
     }
 
     /**
@@ -281,47 +288,72 @@ public class DelegatingDecompressorFrameListener extends Http2FrameListenerDecor
     }
 
     /**
-     * Garbage collector which translates post-decompression amounts the application knows about
+     * A decorator around the local flow controller that converts consumed bytes from uncompressed to compressed.
-     * to pre-decompression amounts that flow control knows about.
      */
-    private static final class DecompressorGarbageCollector implements Http2FlowControlWindowManager {
+    private final class ConsumedBytesConverter implements Http2LocalFlowController {
-        private final Http2FlowControlWindowManager original;
+        private final Http2LocalFlowController flowController;
 
-        DecompressorGarbageCollector(Http2FlowControlWindowManager original) {
+        ConsumedBytesConverter(Http2LocalFlowController flowController) {
-            this.original = original;
+            this.flowController = checkNotNull(flowController, "flowController");
         }
 
         @Override
-        public void returnProcessedBytes(ChannelHandlerContext ctx, int numBytes) throws Http2Exception {
+        public void initialWindowSize(int newWindowSize) throws Http2Exception {
-            final Http2Stream stream = stream();
+            flowController.initialWindowSize(newWindowSize);
-            final Http2Decompressor decompressor = stream.getProperty(Http2Decompressor.class);
+        }
 
-            // Make a copy before hand in case any exceptions occur we will roll back the state
+        @Override
-            Http2Decompressor copy = new Http2Decompressor(decompressor);
+        public int initialWindowSize() {
+            return flowController.initialWindowSize();
+        }
+
+        @Override
+        public int windowSize(Http2Stream stream) {
+            return flowController.windowSize(stream);
+        }
+
+        @Override
+        public void incrementWindowSize(ChannelHandlerContext ctx, Http2Stream stream, int delta)
+                throws Http2Exception {
+            flowController.incrementWindowSize(ctx, stream, delta);
+        }
+
+        @Override
+        public void receiveFlowControlledFrame(ChannelHandlerContext ctx, Http2Stream stream,
+                ByteBuf data, int padding, boolean endOfStream) throws Http2Exception {
+            flowController.receiveFlowControlledFrame(ctx, stream, data, padding, endOfStream);
+        }
+
+        @Override
+        public void consumeBytes(ChannelHandlerContext ctx, Http2Stream stream, int numBytes)
+                throws Http2Exception {
+            Http2Decompressor decompressor = decompressor(stream);
+            Http2Decompressor copy = null;
             try {
-                original.returnProcessedBytes(ctx, decompressor.consumeProcessedBytes(numBytes));
+                if (decompressor != null) {
+                    // Make a copy before hand in case any exceptions occur we will roll back the state
+                    copy = new Http2Decompressor(decompressor);
+                    // Convert the uncompressed consumed bytes to compressed (on the wire) bytes.
+                    numBytes = decompressor.consumeProcessedBytes(numBytes);
+                }
+                flowController.consumeBytes(ctx, stream, numBytes);
             } catch (Http2Exception e) {
+                if (copy != null) {
                     stream.setProperty(Http2Decompressor.class, copy);
+                }
                 throw e;
             } catch (Throwable t) {
+                if (copy != null) {
                     stream.setProperty(Http2Decompressor.class, copy);
+                }
                 throw new Http2Exception(INTERNAL_ERROR,
                         "Error while returning bytes to flow control window", t);
             }
         }
 
-        Http2FlowControlWindowManager original() {
-            return original;
-        }
-
         @Override
-        public int unProcessedBytes() {
+        public int unconsumedBytes(Http2Stream stream) {
-            return original.unProcessedBytes();
+            return flowController.unconsumedBytes(stream);
-        }
-
-        @Override
-        public Http2Stream stream() {
-            return original.stream();
         }
     }
 

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2Connection.java

@@ -91,7 +91,7 @@ public interface Http2Connection {
     /**
      * A view of the connection from one endpoint (local or remote).
      */
-    interface Endpoint {
+    interface Endpoint<F extends Http2FlowController> {
 
         /**
          * Returns the next valid streamId for this endpoint. If negative, the stream IDs are
@@ -186,10 +186,20 @@ public interface Http2Connection {
          */
         int lastKnownStream();
 
+        /**
+         * Gets the flow controller for this endpoint.
+         */
+        F flowController();
+
+        /**
+         * Sets the flow controller for this endpoint.
+         */
+        void flowController(F flowController);
+
         /**
          * Gets the {@link Endpoint} opposite this one.
          */
-        Endpoint opposite();
+        Endpoint<? extends Http2FlowController> opposite();
     }
 
     /**
@@ -237,7 +247,7 @@ public interface Http2Connection {
     /**
      * Gets a view of this connection from the local {@link Endpoint}.
      */
-    Endpoint local();
+    Endpoint<Http2LocalFlowController> local();
 
     /**
      * Creates a new stream initiated by the local endpoint. See {@link Endpoint#createStream(int, boolean)}.
@@ -247,7 +257,7 @@ public interface Http2Connection {
     /**
      * Gets a view of this connection from the remote {@link Endpoint}.
      */
-    Endpoint remote();
+    Endpoint<Http2RemoteFlowController> remote();
 
     /**
      * Creates a new stream initiated by the remote endpoint. See {@link Endpoint#createStream(int, boolean)}.

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2ConnectionDecoder.java

@@ -48,11 +48,6 @@ public interface Http2ConnectionDecoder extends Closeable {
          */
         Http2LifecycleManager lifecycleManager();
 
-        /**
-         * Sets the {@link Http2InboundFlowController} to be used when building the decoder.
-         */
-        Builder inboundFlow(Http2InboundFlowController inboundFlow);
-
         /**
          * Sets the {@link Http2FrameReader} to be used when building the decoder.
          */
@@ -79,6 +74,11 @@ public interface Http2ConnectionDecoder extends Closeable {
      */
     Http2Connection connection();
 
+    /**
+     * Provides the local flow controller for managing inbound traffic.
+     */
+    Http2LocalFlowController flowController();
+
     /**
      * Provides direct access to the underlying frame listener.
      */

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2ConnectionEncoder.java

@@ -23,7 +23,7 @@ import io.netty.channel.ChannelPromise;
 /**
  * Handler for outbound HTTP/2 traffic.
  */
-public interface Http2ConnectionEncoder extends Http2FrameWriter, Http2OutboundFlowController {
+public interface Http2ConnectionEncoder extends Http2FrameWriter {
 
     /**
      * Builder for new instances of {@link Http2ConnectionEncoder}.
@@ -50,11 +50,6 @@ public interface Http2ConnectionEncoder extends Http2FrameWriter, Http2OutboundF
          */
         Builder frameWriter(Http2FrameWriter frameWriter);
 
-        /**
-         * Sets the {@link Http2OutboundFlowController} to be used when building the encoder.
-         */
-        Builder outboundFlow(Http2OutboundFlowController outboundFlow);
-
         /**
          * Creates a new encoder instance.
          */
@@ -66,6 +61,11 @@ public interface Http2ConnectionEncoder extends Http2FrameWriter, Http2OutboundF
      */
     Http2Connection connection();
 
+    /**
+     * Provides the remote flow controller for managing outbound traffic.
+     */
+    Http2RemoteFlowController flowController();
+
     /**
      * Provides direct access to the underlying frame writer object.
      */

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2ConnectionHandler.java

@@ -60,18 +60,10 @@ public class Http2ConnectionHandler extends ByteToMessageDecoder implements Http
 
     public Http2ConnectionHandler(Http2Connection connection, Http2FrameReader frameReader,
             Http2FrameWriter frameWriter, Http2FrameListener listener) {
-        this(connection, frameReader, frameWriter, new DefaultHttp2InboundFlowController(
-                connection, frameWriter), new DefaultHttp2OutboundFlowController(connection,
-                frameWriter), listener);
-    }
-
-    public Http2ConnectionHandler(Http2Connection connection, Http2FrameReader frameReader,
-            Http2FrameWriter frameWriter, Http2InboundFlowController inboundFlow,
-            Http2OutboundFlowController outboundFlow, Http2FrameListener listener) {
         this(DefaultHttp2ConnectionDecoder.newBuilder().connection(connection)
-                .frameReader(frameReader).inboundFlow(inboundFlow).listener(listener),
+                .frameReader(frameReader).listener(listener),
              DefaultHttp2ConnectionEncoder.newBuilder().connection(connection)
-                .frameWriter(frameWriter).outboundFlow(outboundFlow));
+                .frameWriter(frameWriter));
     }
 
     /**

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2FlowControlWindowManager.java

@@ -1,44 +0,0 @@
-/*
- * Copyright 2014 The Netty Project
- *
- * The Netty Project licenses this file to you under the Apache License, version 2.0 (the
- * "License"); you may not use this file except in compliance with the License. You may obtain a
- * copy of the License at:
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software distributed under the License
- * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
- * or implied. See the License for the specific language governing permissions and limitations under
- * the License.
- */
-package io.netty.handler.codec.http2;
-
-import io.netty.channel.ChannelHandlerContext;
-
-/**
- * Allows data to be returned to the flow control window.
- */
-public interface Http2FlowControlWindowManager {
-    /**
-     * Used by applications that participate in application-level inbound flow control. Allows the
-     * application to return a number of bytes that has been processed and thereby enabling the
-     * {@link Http2InboundFlowController} to send a {@code WINDOW_UPDATE} to restore at least part
-     * of the flow control window.
-     *
-     * @param ctx the channel handler context to use when sending a {@code WINDOW_UPDATE} if
-     *            appropriate
-     * @param numBytes the number of bytes to be returned to the flow control window.
-     */
-    void returnProcessedBytes(ChannelHandlerContext ctx, int numBytes) throws Http2Exception;
-
-    /**
-     * The number of bytes that are outstanding and have not yet been returned to the flow controller.
-     */
-    int unProcessedBytes();
-
-    /**
-     * Get the stream that is being managed
-     */
-    Http2Stream stream();
-}

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2FlowController.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2014 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License, version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License. You may obtain a
+ * copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package io.netty.handler.codec.http2;
+
+import io.netty.channel.ChannelHandlerContext;
+
+/**
+ * Base interface for all HTTP/2 flow controllers.
+ */
+public interface Http2FlowController {
+
+    /**
+     * Sets the initial flow control window and updates all stream windows (but not the connection
+     * window) by the delta.
+     * <p>
+     * This method is used to apply the {@code SETTINGS_INITIAL_WINDOW_SIZE} value for an
+     * {@code SETTINGS} frame.
+     *
+     * @param newWindowSize the new initial window size.
+     * @throws Http2Exception thrown if any protocol-related error occurred.
+     */
+    void initialWindowSize(int newWindowSize) throws Http2Exception;
+
+    /**
+     * Gets the initial flow control window size that is used as the basis for new stream flow
+     * control windows.
+     */
+    int initialWindowSize();
+
+    /**
+     * Gets the number of bytes remaining in the flow control window size for the given stream.
+     *
+     * @param stream The subject stream. Use {@link Http2Connection#connectionStream()} for
+     *            requesting the size of the connection window.
+     * @return the current size of the flow control window.
+     * @throws IllegalArgumentException if the given stream does not exist.
+     */
+    int windowSize(Http2Stream stream);
+
+    /**
+     * Increments the size of the stream's flow control window by the given delta.
+     * <p>
+     * In the case of a {@link Http2RemoteFlowController} this is called upon receipt of a
+     * {@code WINDOW_UPDATE} frame from the remote endpoint to mirror the changes to the window
+     * size.
+     * <p>
+     * For a {@link Http2LocalFlowController} this can be called to request the expansion of the
+     * window size published by this endpoint. It is up to the implementation, however, as to when a
+     * {@code WINDOW_UPDATE} is actually sent.
+     *
+     * @param ctx The context for the calling handler
+     * @param stream The subject stream. Use {@link Http2Connection#connectionStream()} for
+     *            requesting the size of the connection window.
+     * @param delta the change in size of the flow control window.
+     * @throws Http2Exception thrown if a protocol-related error occurred.
+     */
+    void incrementWindowSize(ChannelHandlerContext ctx, Http2Stream stream, int delta) throws Http2Exception;
+}

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2FlowState.java

@@ -1,27 +0,0 @@
-/*
- * Copyright 2014 The Netty Project
- *
- * The Netty Project licenses this file to you under the Apache License, version 2.0 (the
- * "License"); you may not use this file except in compliance with the License. You may obtain a
- * copy of the License at:
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software distributed under the License
- * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
- * or implied. See the License for the specific language governing permissions and limitations under
- * the License.
- */
-package io.netty.handler.codec.http2;
-
-/**
- * Base interface for flow-control state for a particular stream.
- */
-public interface Http2FlowState {
-
-    /**
-     * Returns the current remaining flow control window (in bytes) for the stream. Depending on the
-     * flow control implementation, this value may be negative.
-     */
-    int window();
-}

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2InboundFlowController.java

@@ -1,77 +0,0 @@
-/*
- * Copyright 2014 The Netty Project
- *
- * The Netty Project licenses this file to you under the Apache License, version 2.0 (the
- * "License"); you may not use this file except in compliance with the License. You may obtain a
- * copy of the License at:
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software distributed under the License
- * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
- * or implied. See the License for the specific language governing permissions and limitations under
- * the License.
- */
-
-package io.netty.handler.codec.http2;
-
-import io.netty.buffer.ByteBuf;
-import io.netty.channel.ChannelHandlerContext;
-
-/**
- * Controls the inbound flow of data frames from the remote endpoint.
- */
-public interface Http2InboundFlowController {
-
-    /**
-     * Applies inbound flow control to the given {@code DATA} frame.
-     *
-     * @param ctx the context from the handler where the frame was read.
-     * @param streamId the subject stream for the frame.
-     * @param data payload buffer for the frame.
-     * @param padding the number of padding bytes found at the end of the frame.
-     * @param endOfStream Indicates whether this is the last frame to be sent from the remote
-     *            endpoint for this stream.
-     */
-    void applyFlowControl(ChannelHandlerContext ctx, int streamId, ByteBuf data, int padding,
-            boolean endOfStream) throws Http2Exception;
-
-    /**
-     * Sets the global inbound flow control window size and updates all stream window sizes by the delta.
-     * <p>
-     * This method is used to apply the {@code SETTINGS_INITIAL_WINDOW_SIZE} value for an
-     * outbound {@code SETTINGS} frame.
-     * <p>
-     * The connection stream windows will not be modified as a result of this call.
-     * @param newWindowSize the new initial window size.
-     * @throws Http2Exception thrown if any protocol-related error occurred.
-     */
-    void initialWindowSize(int newWindowSize) throws Http2Exception;
-
-    /**
-     * Gets the initial window size used as the basis for new stream flow control windows.
-     */
-    int initialWindowSize();
-
-    /**
-     * Sets the initial inbound flow control window size for a specific stream.
-     * <p>
-     * Note it is the responsibly of the caller to ensure that the the
-     * initial {@code SETTINGS} frame is sent before this is called. It would
-     * be considered a {@link Http2Error#PROTOCOL_ERROR} if a {@code WINDOW_UPDATE}
-     * was generated by this method before the initial {@code SETTINGS} frame is sent.
-     * @param ctx the context to use if a {@code WINDOW_UPDATE} is determined necessary.
-     * @param streamId The stream to update.
-     * @param newWindowSize the window size to apply to {@code streamId}
-     * @throws Http2Exception thrown if any protocol-related error occurred.
-     */
-    void initialStreamWindowSize(ChannelHandlerContext ctx, int streamId, int newWindowSize) throws Http2Exception;
-
-    /**
-     * Obtain the initial window size for a specific stream.
-     * @param streamId The stream id to get the initial window size for.
-     * @return The initial window size for {@code streamId}.
-     * @throws Http2Exception If no stream corresponding to {@code stream} could be found.
-     */
-    int initialStreamWindowSize(int streamId) throws Http2Exception;
-}

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2LocalFlowController.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright 2014 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License, version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License. You may obtain a
+ * copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package io.netty.handler.codec.http2;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandlerContext;
+
+/**
+ * A {@link Http2FlowController} for controlling the inbound flow of {@code DATA} frames from the remote
+ * endpoint.
+ */
+public interface Http2LocalFlowController extends Http2FlowController {
+
+    /**
+     * Receives an inbound {@code DATA} frame from the remote endpoint and applies flow control
+     * policies to it for both the {@code stream} as well as the connection. If any flow control
+     * policies have been violated, an exception is raised immediately, otherwise the frame is
+     * considered to have "passed" flow control.
+     *
+     * @param ctx the context from the handler where the frame was read.
+     * @param stream the subject stream for the received frame. The connection stream object must
+     *            not be used.
+     * @param data payload buffer for the frame.
+     * @param padding the number of padding bytes found at the end of the frame.
+     * @param endOfStream Indicates whether this is the last frame to be sent from the remote
+     *            endpoint for this stream.
+     * @throws Http2Exception if any flow control errors are encountered.
+     */
+    void receiveFlowControlledFrame(ChannelHandlerContext ctx, Http2Stream stream, ByteBuf data, int padding,
+            boolean endOfStream) throws Http2Exception;
+
+    /**
+     * Indicates that the application has consumed a number of bytes for the given stream and is
+     * therefore ready to receive more data from the remote endpoint. The application must consume
+     * any bytes that it receives or the flow control window will collapse. Consuming bytes enables
+     * the flow controller to send {@code WINDOW_UPDATE} to restore a portion of the flow control
+     * window for the stream.
+     *
+     * @param ctx the channel handler context to use when sending a {@code WINDOW_UPDATE} if
+     *            appropriate
+     * @param stream the stream for which window space should be freed. The connection stream object
+     *            must not be used.
+     * @param numBytes the number of bytes to be returned to the flow control window.
+     * @throws Http2Exception if the number of bytes returned exceeds the {@link #unconsumedBytes()}
+     *             for the stream.
+     */
+    void consumeBytes(ChannelHandlerContext ctx, Http2Stream stream, int numBytes) throws Http2Exception;
+
+    /**
+     * The number of bytes for the given stream that have been received but not yet consumed by the
+     * application.
+     *
+     * @param stream the stream for which window space should be freed.
+     * @return the number of unconsumed bytes for the stream.
+     */
+    int unconsumedBytes(Http2Stream stream);
+}

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2OutboundFlowController.java

@@ -1,71 +0,0 @@
-/*
- * Copyright 2014 The Netty Project
- *
- * The Netty Project licenses this file to you under the Apache License, version 2.0 (the
- * "License"); you may not use this file except in compliance with the License. You may obtain a
- * copy of the License at:
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software distributed under the License
- * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
- * or implied. See the License for the specific language governing permissions and limitations under
- * the License.
- */
-
-package io.netty.handler.codec.http2;
-
-import io.netty.buffer.ByteBuf;
-import io.netty.channel.ChannelFuture;
-import io.netty.channel.ChannelHandlerContext;
-import io.netty.channel.ChannelPromise;
-
-
-/**
- * Controls the outbound flow of data frames to the remote endpoint.
- */
-public interface Http2OutboundFlowController extends Http2DataWriter {
-
-    /**
-     * Controls the flow-controlled writing of a DATA frame to the remote endpoint. There is no
-     * guarantee when the data will be written or whether it will be split into multiple frames
-     * before sending. The returned future will only be completed once all of the data has been
-     * successfully written to the remote endpoint.
-     * <p>
-     * Manually flushing the {@link ChannelHandlerContext} is not required, since the flow
-     * controller will flush as appropriate.
-     */
-    @Override
-    ChannelFuture writeData(ChannelHandlerContext ctx, int streamId, ByteBuf data, int padding,
-            boolean endStream, ChannelPromise promise);
-
-    /**
-     * Returns the {@link ChannelFuture} for the most recent write for the given
-     * stream. If no previous write for the stream has occurred, returns {@code null}.
-     */
-    ChannelFuture lastWriteForStream(int streamId);
-
-    /**
-     * Sets the initial size of the connection's outbound flow control window. The outbound flow
-     * control windows for all streams are updated by the delta in the initial window size. This is
-     * called as part of the processing of a SETTINGS frame received from the remote endpoint.
-     *
-     * @param newWindowSize the new initial window size.
-     */
-    void initialOutboundWindowSize(int newWindowSize) throws Http2Exception;
-
-    /**
-     * Gets the initial size of the connection's outbound flow control window.
-     */
-    int initialOutboundWindowSize();
-
-    /**
-     * Updates the size of the stream's outbound flow control window. This is called upon receiving
-     * a WINDOW_UPDATE frame from the remote endpoint.
-     *
-     * @param streamId the ID of the stream, or zero if the window is for the entire connection.
-     * @param deltaWindowSize the change in size of the outbound flow control window.
-     * @throws Http2Exception thrown if a protocol-related error occurred.
-     */
-    void updateOutboundWindowSize(int streamId, int deltaWindowSize) throws Http2Exception;
-}

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2RemoteFlowController.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2014 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License, version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License. You may obtain a
+ * copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package io.netty.handler.codec.http2;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelPromise;
+
+/**
+ * A {@link Http2FlowController} for controlling the flow of outbound {@code DATA} frames to the remote
+ * endpoint.
+ */
+public interface Http2RemoteFlowController extends Http2FlowController {
+
+    /**
+     * Writes or queues a {@code DATA} frame for transmission to the remote endpoint. There is no
+     * guarantee when the data will be written or whether it will be split into multiple frames
+     * before sending. The returned future will only be completed once all of the data has been
+     * successfully written to the remote endpoint.
+     * <p>
+     * Manually flushing the {@link ChannelHandlerContext} is not required, since the flow
+     * controller will flush as appropriate.
+     *
+     * @param ctx the context from the handler.
+     * @param stream the subject stream. Must not be the connection stream object.
+     * @param data payload buffer for the frame.
+     * @param padding the number of padding bytes to be added at the end of the frame.
+     * @param endOfStream Indicates whether this is the last frame to be sent to the remote endpoint
+     *            for this stream.
+     * @param promise the promise to be completed when the data has been successfully written or a
+     *            failure occurs.
+     * @return a future that is completed when the frame is sent to the remote endpoint.
+     */
+    ChannelFuture sendFlowControlledFrame(ChannelHandlerContext ctx, Http2Stream stream,
+            ByteBuf data, int padding, boolean endStream, ChannelPromise promise);
+
+    /**
+     * Gets the {@link ChannelFuture} for the most recent frame that was sent for the given stream
+     * via a call to {@link #sendFlowControlledFrame()}. This is useful for cases such as ensuring
+     * that {@code HEADERS} frames maintain send order with {@code DATA} frames.
+     *
+     * @param stream the subject stream. Must not be the connection stream object.
+     * @return the most recent sent frame, or {@code null} if no frame has been sent for the stream.
+     */
+    ChannelFuture lastFlowControlledFrameSent(Http2Stream stream);
+}

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2Stream.java

@@ -147,36 +147,6 @@ public interface Http2Stream {
      */
     <V> V removeProperty(Object key);
 
-    /**
-     * Gets the in-bound flow control state for this stream.
-     */
-    Http2FlowState inboundFlow();
-
-    /**
-     * Sets the in-bound flow control state for this stream.
-     */
-    void inboundFlow(Http2FlowState state);
-
-    /**
-     * Gets the out-bound flow control window for this stream.
-     */
-    Http2FlowState outboundFlow();
-
-    /**
-     * Sets the out-bound flow control window for this stream.
-     */
-    void outboundFlow(Http2FlowState state);
-
-    /**
-     * Gets the interface which allows bytes to be returned to the flow controller
-     */
-    Http2FlowControlWindowManager garbageCollector();
-
-    /**
-     * Sets the interface which allows bytes to be returned to the flow controller
-     */
-    void garbageCollector(Http2FlowControlWindowManager collector);
-
     /**
      * Updates an priority for this stream. Calling this method may affect the straucture of the
      * priority tree.

codec-http2/src/main/java/io/netty/handler/codec/http2/HttpToHttp2ConnectionHandler.java

@@ -40,10 +40,9 @@ public class HttpToHttp2ConnectionHandler extends Http2ConnectionHandler {
         super(connection, frameReader, frameWriter, listener);
     }
 
-    public HttpToHttp2ConnectionHandler(Http2Connection connection, Http2FrameReader frameReader,
+    public HttpToHttp2ConnectionHandler(Http2ConnectionDecoder.Builder decoderBuilder,
-            Http2FrameWriter frameWriter, Http2InboundFlowController inboundFlow,
+            Http2ConnectionEncoder.Builder encoderBuilder) {
-            Http2OutboundFlowController outboundFlow, Http2FrameListener listener) {
+        super(decoderBuilder, encoderBuilder);
-        super(connection, frameReader, frameWriter, inboundFlow, outboundFlow, listener);
     }
 
     /**

codec-http2/src/test/java/io/netty/handler/codec/http2/DataCompressionHttp2Test.java

@@ -153,7 +153,7 @@ public class DataCompressionHttp2Test {
                 }
             });
             awaitServer();
-            assertEquals(0, stream.garbageCollector().unProcessedBytes());
+            assertEquals(0, serverConnection.local().flowController().unconsumedBytes(stream));
             assertEquals(text, serverOut.toString(CharsetUtil.UTF_8.name()));
         } finally {
             data.release();
@@ -182,7 +182,7 @@ public class DataCompressionHttp2Test {
                 }
             });
             awaitServer();
-            assertEquals(0, stream.garbageCollector().unProcessedBytes());
+            assertEquals(0, serverConnection.local().flowController().unconsumedBytes(stream));
             assertEquals(text, serverOut.toString(CharsetUtil.UTF_8.name()));
         } finally {
             data.release();
@@ -214,7 +214,7 @@ public class DataCompressionHttp2Test {
                 }
             });
             awaitServer();
-            assertEquals(0, stream.garbageCollector().unProcessedBytes());
+            assertEquals(0, serverConnection.local().flowController().unconsumedBytes(stream));
             assertEquals(new StringBuilder(text1).append(text2).toString(),
                     serverOut.toString(CharsetUtil.UTF_8.name()));
         } finally {
@@ -247,7 +247,7 @@ public class DataCompressionHttp2Test {
                 }
             });
             awaitServer();
-            assertEquals(0, stream.garbageCollector().unProcessedBytes());
+            assertEquals(0, serverConnection.local().flowController().unconsumedBytes(stream));
             assertEquals(data.resetReaderIndex().toString(CharsetUtil.UTF_8),
                     serverOut.toString(CharsetUtil.UTF_8.name()));
         } finally {
@@ -294,14 +294,15 @@ public class DataCompressionHttp2Test {
             protected void initChannel(Channel ch) throws Exception {
                 ChannelPipeline p = ch.pipeline();
                 Http2FrameWriter writer = new DefaultHttp2FrameWriter();
-                Http2ConnectionHandler connectionHandler = new Http2ConnectionHandler(
+                Http2ConnectionHandler connectionHandler =
-                        new DefaultHttp2ConnectionDecoder.Builder()
+                        new Http2ConnectionHandler(new DefaultHttp2ConnectionDecoder.Builder()
                                 .connection(serverConnection)
                                 .frameReader(new DefaultHttp2FrameReader())
-                            .inboundFlow(new DefaultHttp2InboundFlowController(serverConnection, writer))
+                                .listener(
-                            .listener(new DelegatingDecompressorFrameListener(serverConnection, serverListener)),
+                                        new DelegatingDecompressorFrameListener(serverConnection,
-                        new CompressorHttp2ConnectionEncoder.Builder().connection(serverConnection).frameWriter(writer)
+                                                serverListener)),
-                                .outboundFlow(new DefaultHttp2OutboundFlowController(serverConnection, writer)));
+                                new CompressorHttp2ConnectionEncoder.Builder().connection(
+                                        serverConnection).frameWriter(writer));
                 p.addLast(connectionHandler);
                 p.addLast(Http2CodecUtil.ignoreSettingsHandler());
                 serverChannelLatch.countDown();
@@ -316,14 +317,15 @@ public class DataCompressionHttp2Test {
                 ChannelPipeline p = ch.pipeline();
                 FrameCountDown clientFrameCountDown = new FrameCountDown(clientListener, clientLatch);
                 Http2FrameWriter writer = new DefaultHttp2FrameWriter();
-                Http2ConnectionHandler connectionHandler = new Http2ConnectionHandler(
+                Http2ConnectionHandler connectionHandler =
-                        new DefaultHttp2ConnectionDecoder.Builder()
+                        new Http2ConnectionHandler(new DefaultHttp2ConnectionDecoder.Builder()
                                 .connection(clientConnection)
                                 .frameReader(new DefaultHttp2FrameReader())
-                            .inboundFlow(new DefaultHttp2InboundFlowController(clientConnection, writer))
+                                .listener(
-                            .listener(new DelegatingDecompressorFrameListener(clientConnection, clientFrameCountDown)),
+                                        new DelegatingDecompressorFrameListener(clientConnection,
-                        new CompressorHttp2ConnectionEncoder.Builder().connection(clientConnection).frameWriter(writer)
+                                                clientFrameCountDown)),
-                                .outboundFlow(new DefaultHttp2OutboundFlowController(clientConnection, writer)));
+                                new CompressorHttp2ConnectionEncoder.Builder().connection(
+                                        clientConnection).frameWriter(writer));
                 clientEncoder = connectionHandler.encoder();
                 p.addLast(connectionHandler);
                 p.addLast(Http2CodecUtil.ignoreSettingsHandler());

codec-http2/src/test/java/io/netty/handler/codec/http2/DefaultHttp2ConnectionDecoderTest.java

@@ -70,13 +70,16 @@ public class DefaultHttp2ConnectionDecoderTest {
     private Http2Connection connection;
 
     @Mock
-    private Http2Connection.Endpoint remote;
+    private Http2Connection.Endpoint<Http2RemoteFlowController> remote;
 
     @Mock
-    private Http2Connection.Endpoint local;
+    private Http2Connection.Endpoint<Http2LocalFlowController> local;
 
     @Mock
-    private Http2InboundFlowController inboundFlow;
+    private Http2LocalFlowController localFlow;
+
+    @Mock
+    private Http2RemoteFlowController remoteFlow;
 
     @Mock
     private ChannelHandlerContext ctx;
@@ -104,9 +107,6 @@ public class DefaultHttp2ConnectionDecoderTest {
     @Mock
     private Http2ConnectionEncoder encoder;
 
-    @Mock
-    private Http2FlowControlWindowManager inFlowState;
-
     @Mock
     private Http2LifecycleManager lifecycleManager;
 
@@ -119,12 +119,13 @@ public class DefaultHttp2ConnectionDecoderTest {
         when(channel.isActive()).thenReturn(true);
         when(stream.id()).thenReturn(STREAM_ID);
         when(stream.state()).thenReturn(OPEN);
-        when(stream.garbageCollector()).thenReturn(inFlowState);
         when(pushStream.id()).thenReturn(PUSH_STREAM_ID);
         when(connection.activeStreams()).thenReturn(Collections.singletonList(stream));
         when(connection.stream(STREAM_ID)).thenReturn(stream);
         when(connection.requireStream(STREAM_ID)).thenReturn(stream);
         when(connection.local()).thenReturn(local);
+        when(local.flowController()).thenReturn(localFlow);
+        when(encoder.flowController()).thenReturn(remoteFlow);
         when(connection.remote()).thenReturn(remote);
         doAnswer(new Answer<Http2Stream>() {
             @Override
@@ -151,7 +152,7 @@ public class DefaultHttp2ConnectionDecoderTest {
         when(ctx.write(any())).thenReturn(future);
 
         decoder = DefaultHttp2ConnectionDecoder.newBuilder().connection(connection)
-                        .frameReader(reader).inboundFlow(inboundFlow).encoder(encoder)
+                        .frameReader(reader).encoder(encoder)
                         .listener(listener).lifecycleManager(lifecycleManager).build();
 
         // Simulate receiving the initial settings from the remote endpoint.
@@ -173,8 +174,8 @@ public class DefaultHttp2ConnectionDecoderTest {
         mockFlowControl(processedBytes);
         try {
             decode().onDataRead(ctx, STREAM_ID, data, 10, true);
-            verify(inboundFlow).applyFlowControl(eq(ctx), eq(STREAM_ID), eq(data), eq(padding), eq(true));
+            verify(localFlow).receiveFlowControlledFrame(eq(ctx), eq(stream), eq(data), eq(padding), eq(true));
-            verify(inFlowState).returnProcessedBytes(eq(ctx), eq(processedBytes));
+            verify(localFlow).consumeBytes(eq(ctx), eq(stream), eq(processedBytes));
 
             // Verify that the event was absorbed and not propagated to the oberver.
             verify(listener, never()).onDataRead(eq(ctx), anyInt(), any(ByteBuf.class), anyInt(), anyBoolean());
@@ -203,7 +204,7 @@ public class DefaultHttp2ConnectionDecoderTest {
         final ByteBuf data = dummyData();
         try {
             decode().onDataRead(ctx, STREAM_ID, data, 10, true);
-            verify(inboundFlow, never()).applyFlowControl(eq(ctx), eq(STREAM_ID), eq(data), eq(10), eq(true));
+            verify(localFlow, never()).receiveFlowControlledFrame(eq(ctx), eq(stream), eq(data), eq(10), eq(true));
             verify(listener, never()).onDataRead(eq(ctx), anyInt(), any(ByteBuf.class), anyInt(), anyBoolean());
         } finally {
             data.release();
@@ -218,7 +219,7 @@ public class DefaultHttp2ConnectionDecoderTest {
         final ByteBuf data = dummyData();
         try {
             decode().onDataRead(ctx, STREAM_ID, data, 10, true);
-            verify(inboundFlow).applyFlowControl(eq(ctx), eq(STREAM_ID), eq(data), eq(10), eq(true));
+            verify(localFlow).receiveFlowControlledFrame(eq(ctx), eq(stream), eq(data), eq(10), eq(true));
             verify(listener, never()).onDataRead(eq(ctx), anyInt(), any(ByteBuf.class), anyInt(), anyBoolean());
         } finally {
             data.release();
@@ -230,7 +231,7 @@ public class DefaultHttp2ConnectionDecoderTest {
         final ByteBuf data = dummyData();
         try {
             decode().onDataRead(ctx, STREAM_ID, data, 10, true);
-            verify(inboundFlow).applyFlowControl(eq(ctx), eq(STREAM_ID), eq(data), eq(10), eq(true));
+            verify(localFlow).receiveFlowControlledFrame(eq(ctx), eq(stream), eq(data), eq(10), eq(true));
             verify(lifecycleManager).closeRemoteSide(eq(stream), eq(future));
             verify(listener).onDataRead(eq(ctx), eq(STREAM_ID), eq(data), eq(10), eq(true));
         } finally {
@@ -248,23 +249,23 @@ public class DefaultHttp2ConnectionDecoderTest {
             public Integer answer(InvocationOnMock in) throws Throwable {
                 return unprocessed.get();
             }
-        }).when(inFlowState).unProcessedBytes();
+        }).when(localFlow).unconsumedBytes(eq(stream));
         doAnswer(new Answer<Void>() {
             @Override
             public Void answer(InvocationOnMock in) throws Throwable {
-                int delta = (Integer) in.getArguments()[1];
+                int delta = (Integer) in.getArguments()[2];
                 int newValue = unprocessed.addAndGet(-delta);
                 if (newValue < 0) {
                     throw new RuntimeException("Returned too many bytes");
                 }
                 return null;
             }
-        }).when(inFlowState).returnProcessedBytes(eq(ctx), anyInt());
+        }).when(localFlow).consumeBytes(eq(ctx), eq(stream), anyInt());
         // When the listener callback is called, process a few bytes and then throw.
         doAnswer(new Answer<Integer>() {
             @Override
             public Integer answer(InvocationOnMock in) throws Throwable {
-                inFlowState.returnProcessedBytes(ctx, 4);
+                localFlow.consumeBytes(ctx, stream, 4);
                 throw new RuntimeException("Fake Exception");
             }
         }).when(listener).onDataRead(eq(ctx), eq(STREAM_ID), any(ByteBuf.class), eq(10), eq(true));
@@ -272,11 +273,11 @@ public class DefaultHttp2ConnectionDecoderTest {
             decode().onDataRead(ctx, STREAM_ID, data, padding, true);
             fail("Expected exception");
         } catch (RuntimeException cause) {
-            verify(inboundFlow)
+            verify(localFlow)
-                    .applyFlowControl(eq(ctx), eq(STREAM_ID), eq(data), eq(padding), eq(true));
+                    .receiveFlowControlledFrame(eq(ctx), eq(stream), eq(data), eq(padding), eq(true));
             verify(lifecycleManager).closeRemoteSide(eq(stream), eq(future));
             verify(listener).onDataRead(eq(ctx), eq(STREAM_ID), eq(data), eq(padding), eq(true));
-            assertEquals(0, inFlowState.unProcessedBytes());
+            assertEquals(0, localFlow.unconsumedBytes(stream));
         } finally {
             data.release();
         }
@@ -365,7 +366,7 @@ public class DefaultHttp2ConnectionDecoderTest {
     public void windowUpdateReadAfterGoAwayShouldBeIgnored() throws Exception {
         when(connection.goAwaySent()).thenReturn(true);
         decode().onWindowUpdateRead(ctx, STREAM_ID, 10);
-        verify(encoder, never()).updateOutboundWindowSize(anyInt(), anyInt());
+        verify(remoteFlow, never()).incrementWindowSize(eq(ctx), any(Http2Stream.class), anyInt());
         verify(listener, never()).onWindowUpdateRead(eq(ctx), anyInt(), anyInt());
     }
 
@@ -378,7 +379,7 @@ public class DefaultHttp2ConnectionDecoderTest {
     @Test
     public void windowUpdateReadShouldSucceed() throws Exception {
         decode().onWindowUpdateRead(ctx, STREAM_ID, 10);
-        verify(encoder).updateOutboundWindowSize(eq(STREAM_ID), eq(10));
+        verify(remoteFlow).incrementWindowSize(eq(ctx), eq(stream), eq(10));
         verify(listener).onWindowUpdateRead(eq(ctx), eq(STREAM_ID), eq(10));
     }
 

codec-http2/src/test/java/io/netty/handler/codec/http2/DefaultHttp2ConnectionEncoderTest.java

@@ -67,13 +67,13 @@ public class DefaultHttp2ConnectionEncoderTest {
     private Http2Connection connection;
 
     @Mock
-    private Http2Connection.Endpoint remote;
+    private Http2Connection.Endpoint<Http2RemoteFlowController> remote;
 
     @Mock
-    private Http2Connection.Endpoint local;
+    private Http2Connection.Endpoint<Http2LocalFlowController> local;
 
     @Mock
-    private Http2OutboundFlowController outboundFlow;
+    private Http2RemoteFlowController remoteFlow;
 
     @Mock
     private ChannelHandlerContext ctx;
@@ -116,6 +116,7 @@ public class DefaultHttp2ConnectionEncoderTest {
         when(connection.requireStream(STREAM_ID)).thenReturn(stream);
         when(connection.local()).thenReturn(local);
         when(connection.remote()).thenReturn(remote);
+        when(remote.flowController()).thenReturn(remoteFlow);
         doAnswer(new Answer<Http2Stream>() {
             @Override
             public Http2Stream answer(InvocationOnMock invocation) throws Throwable {
@@ -135,9 +136,10 @@ public class DefaultHttp2ConnectionEncoderTest {
         when(remote.createStream(eq(STREAM_ID), anyBoolean())).thenReturn(stream);
         when(remote.reservePushStream(eq(PUSH_STREAM_ID), eq(stream))).thenReturn(pushStream);
         when(writer.writeSettings(eq(ctx), any(Http2Settings.class), eq(promise))).thenReturn(future);
-        when(writer.writeGoAway(eq(ctx), anyInt(), anyInt(), any(ByteBuf.class), eq(promise))).thenReturn(future);
+        when(writer.writeGoAway(eq(ctx), anyInt(), anyInt(), any(ByteBuf.class), eq(promise)))
-        when(outboundFlow.writeData(eq(ctx), anyInt(), any(ByteBuf.class), anyInt(), anyBoolean(), eq(promise)))
                 .thenReturn(future);
+        when(remoteFlow.sendFlowControlledFrame(eq(ctx), any(Http2Stream.class),
+                 any(ByteBuf.class), anyInt(), anyBoolean(), eq(promise))).thenReturn(future);
         when(ctx.alloc()).thenReturn(UnpooledByteBufAllocator.DEFAULT);
         when(ctx.channel()).thenReturn(channel);
         when(ctx.newSucceededFuture()).thenReturn(future);
@@ -145,8 +147,7 @@ public class DefaultHttp2ConnectionEncoderTest {
         when(ctx.write(any())).thenReturn(future);
 
         encoder = DefaultHttp2ConnectionEncoder.newBuilder().connection(connection)
-                        .frameWriter(writer).outboundFlow(outboundFlow)
+                        .frameWriter(writer).lifecycleManager(lifecycleManager).build();
-                        .lifecycleManager(lifecycleManager).build();
     }
 
     @Test
@@ -168,7 +169,7 @@ public class DefaultHttp2ConnectionEncoderTest {
         final ByteBuf data = dummyData();
         try {
             encoder.writeData(ctx, STREAM_ID, data, 0, false, promise);
-            verify(outboundFlow).writeData(eq(ctx), eq(STREAM_ID), eq(data), eq(0), eq(false), eq(promise));
+            verify(remoteFlow).sendFlowControlledFrame(eq(ctx), eq(stream), eq(data), eq(0), eq(false), eq(promise));
         } finally {
             data.release();
         }
@@ -180,7 +181,7 @@ public class DefaultHttp2ConnectionEncoderTest {
         final ByteBuf data = dummyData();
         try {
             encoder.writeData(ctx, STREAM_ID, data, 0, true, promise);
-            verify(outboundFlow).writeData(eq(ctx), eq(STREAM_ID), eq(data), eq(0), eq(true), eq(promise));
+            verify(remoteFlow).sendFlowControlledFrame(eq(ctx), eq(stream), eq(data), eq(0), eq(true), eq(promise));
 
             // Invoke the listener callback indicating that the write completed successfully.
             ArgumentCaptor<ChannelFutureListener> captor = ArgumentCaptor.forClass(ChannelFutureListener.class);
@@ -240,7 +241,7 @@ public class DefaultHttp2ConnectionEncoderTest {
         }).when(future).addListener(any(ChannelFutureListener.class));
 
         // Indicate that there was a previous data write operation that the headers must wait for.
-        when(outboundFlow.lastWriteForStream(anyInt())).thenReturn(future);
+        when(remoteFlow.lastFlowControlledFrameSent(any(Http2Stream.class))).thenReturn(future);
         encoder.writeHeaders(ctx, STREAM_ID, EmptyHttp2Headers.INSTANCE, 0, true, promise);
         verify(writer, never()).writeHeaders(eq(ctx), eq(STREAM_ID), eq(EmptyHttp2Headers.INSTANCE), eq(0),
                 eq(DEFAULT_PRIORITY_WEIGHT), eq(false), eq(0), eq(true), eq(promise));

codec-http2/src/test/java/io/netty/handler/codec/http2/DefaultHttp2LocalFlowControllerTest.java

@@ -36,12 +36,12 @@ import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
 /**
- * Tests for {@link DefaultHttp2InboundFlowController}.
+ * Tests for {@link DefaultHttp2LocalFlowController}.
  */
-public class DefaultHttp2InboundFlowControllerTest {
+public class DefaultHttp2LocalFlowControllerTest {
     private static final int STREAM_ID = 1;
 
-    private DefaultHttp2InboundFlowController controller;
+    private DefaultHttp2LocalFlowController controller;
 
     @Mock
     private ByteBuf buffer;
@@ -66,28 +66,28 @@ public class DefaultHttp2InboundFlowControllerTest {
         when(ctx.newPromise()).thenReturn(promise);
 
         connection = new DefaultHttp2Connection(false);
-        controller = new DefaultHttp2InboundFlowController(connection, frameWriter, updateRatio);
+        controller = new DefaultHttp2LocalFlowController(connection, frameWriter, updateRatio);
 
         connection.local().createStream(STREAM_ID, false);
     }
 
     @Test
     public void dataFrameShouldBeAccepted() throws Http2Exception {
-        applyFlowControl(STREAM_ID, 10, 0, false);
+        receiveFlowControlledFrame(STREAM_ID, 10, 0, false);
         verifyWindowUpdateNotSent();
     }
 
     @Test
     public void windowUpdateShouldSendOnceBytesReturned() throws Http2Exception {
         int dataSize = (int) (DEFAULT_WINDOW_SIZE * updateRatio) + 1;
-        applyFlowControl(STREAM_ID, dataSize, 0, false);
+        receiveFlowControlledFrame(STREAM_ID, dataSize, 0, false);
 
         // Return only a few bytes and verify that the WINDOW_UPDATE hasn't been sent.
-        returnProcessedBytes(STREAM_ID, 10);
+        consumeBytes(STREAM_ID, 10);
         verifyWindowUpdateNotSent(CONNECTION_STREAM_ID);
 
         // Return the rest and verify the WINDOW_UPDATE is sent.
-        returnProcessedBytes(STREAM_ID, dataSize - 10);
+        consumeBytes(STREAM_ID, dataSize - 10);
         verifyWindowUpdateSent(STREAM_ID, dataSize);
         verifyWindowUpdateSent(CONNECTION_STREAM_ID, dataSize);
     }
@@ -95,7 +95,7 @@ public class DefaultHttp2InboundFlowControllerTest {
     @Test(expected = Http2Exception.class)
     public void connectionFlowControlExceededShouldThrow() throws Http2Exception {
         // Window exceeded because of the padding.
-        applyFlowControl(STREAM_ID, DEFAULT_WINDOW_SIZE, 1, true);
+        receiveFlowControlledFrame(STREAM_ID, DEFAULT_WINDOW_SIZE, 1, true);
     }
 
     @Test
@@ -103,11 +103,11 @@ public class DefaultHttp2InboundFlowControllerTest {
         int dataSize = (int) (DEFAULT_WINDOW_SIZE * updateRatio) + 1;
 
         // Set end-of-stream on the frame, so no window update will be sent for the stream.
-        applyFlowControl(STREAM_ID, dataSize, 0, true);
+        receiveFlowControlledFrame(STREAM_ID, dataSize, 0, true);
         verifyWindowUpdateNotSent(CONNECTION_STREAM_ID);
         verifyWindowUpdateNotSent(STREAM_ID);
 
-        returnProcessedBytes(STREAM_ID, dataSize);
+        consumeBytes(STREAM_ID, dataSize);
         verifyWindowUpdateSent(CONNECTION_STREAM_ID, dataSize);
         verifyWindowUpdateNotSent(STREAM_ID);
     }
@@ -119,8 +119,8 @@ public class DefaultHttp2InboundFlowControllerTest {
         int windowDelta = getWindowDelta(initialWindowSize, initialWindowSize, dataSize);
 
         // Don't set end-of-stream so we'll get a window update for the stream as well.
-        applyFlowControl(STREAM_ID, dataSize, 0, false);
+        receiveFlowControlledFrame(STREAM_ID, dataSize, 0, false);
-        returnProcessedBytes(STREAM_ID, dataSize);
+        consumeBytes(STREAM_ID, dataSize);
         verifyWindowUpdateSent(CONNECTION_STREAM_ID, windowDelta);
         verifyWindowUpdateSent(STREAM_ID, windowDelta);
     }
@@ -129,10 +129,10 @@ public class DefaultHttp2InboundFlowControllerTest {
     public void initialWindowUpdateShouldAllowMoreFrames() throws Http2Exception {
         // Send a frame that takes up the entire window.
         int initialWindowSize = DEFAULT_WINDOW_SIZE;
-        applyFlowControl(STREAM_ID, initialWindowSize, 0, false);
+        receiveFlowControlledFrame(STREAM_ID, initialWindowSize, 0, false);
         assertEquals(0, window(STREAM_ID));
         assertEquals(0, window(CONNECTION_STREAM_ID));
-        returnProcessedBytes(STREAM_ID, initialWindowSize);
+        consumeBytes(STREAM_ID, initialWindowSize);
         assertEquals(initialWindowSize, window(STREAM_ID));
         assertEquals(DEFAULT_WINDOW_SIZE, window(CONNECTION_STREAM_ID));
 
@@ -146,8 +146,8 @@ public class DefaultHttp2InboundFlowControllerTest {
         reset(frameWriter);
 
         // Send the next frame and verify that the expected window updates were sent.
-        applyFlowControl(STREAM_ID, initialWindowSize, 0, false);
+        receiveFlowControlledFrame(STREAM_ID, initialWindowSize, 0, false);
-        returnProcessedBytes(STREAM_ID, initialWindowSize);
+        consumeBytes(STREAM_ID, initialWindowSize);
         int delta = newInitialWindowSize - initialWindowSize;
         verifyWindowUpdateSent(STREAM_ID, delta);
         verifyWindowUpdateSent(CONNECTION_STREAM_ID, delta);
@@ -164,12 +164,12 @@ public class DefaultHttp2InboundFlowControllerTest {
 
             // Test that both stream and connection window are updated (or not updated) together
             int data1 = (int) (DEFAULT_WINDOW_SIZE * updateRatio) + 1;
-            applyFlowControl(STREAM_ID, data1, 0, false);
+            receiveFlowControlledFrame(STREAM_ID, data1, 0, false);
             verifyWindowUpdateNotSent(STREAM_ID);
             verifyWindowUpdateNotSent(CONNECTION_STREAM_ID);
             assertEquals(DEFAULT_WINDOW_SIZE - data1, window(STREAM_ID));
             assertEquals(DEFAULT_WINDOW_SIZE - data1, window(CONNECTION_STREAM_ID));
-            returnProcessedBytes(STREAM_ID, data1);
+            consumeBytes(STREAM_ID, data1);
             verifyWindowUpdateSent(STREAM_ID, data1);
             verifyWindowUpdateSent(CONNECTION_STREAM_ID, data1);
 
@@ -180,16 +180,16 @@ public class DefaultHttp2InboundFlowControllerTest {
             // a window update for the connection stream.
             --data1;
             int data2 = data1 >> 1;
-            applyFlowControl(STREAM_ID, data1, 0, false);
+            receiveFlowControlledFrame(STREAM_ID, data1, 0, false);
-            applyFlowControl(newStreamId, data1, 0, false);
+            receiveFlowControlledFrame(newStreamId, data1, 0, false);
             verifyWindowUpdateNotSent(STREAM_ID);
             verifyWindowUpdateNotSent(newStreamId);
             verifyWindowUpdateNotSent(CONNECTION_STREAM_ID);
             assertEquals(DEFAULT_WINDOW_SIZE - data1, window(STREAM_ID));
             assertEquals(DEFAULT_WINDOW_SIZE - data1, window(newStreamId));
             assertEquals(DEFAULT_WINDOW_SIZE - (data1 << 1), window(CONNECTION_STREAM_ID));
-            returnProcessedBytes(STREAM_ID, data1);
+            consumeBytes(STREAM_ID, data1);
-            returnProcessedBytes(newStreamId, data2);
+            consumeBytes(newStreamId, data2);
             verifyWindowUpdateNotSent(STREAM_ID);
             verifyWindowUpdateNotSent(newStreamId);
             verifyWindowUpdateSent(CONNECTION_STREAM_ID, data1 + data2);
@@ -216,26 +216,27 @@ public class DefaultHttp2InboundFlowControllerTest {
 
     private void testRatio(float ratio, int newDefaultWindowSize, int newStreamId, boolean setStreamRatio)
             throws Http2Exception {
-        controller.initialStreamWindowSize(ctx, 0, newDefaultWindowSize);
+        int delta = newDefaultWindowSize - DEFAULT_WINDOW_SIZE;
-        connection.local().createStream(newStreamId, false);
+        controller.incrementWindowSize(ctx, stream(0), delta);
+        Http2Stream stream = connection.local().createStream(newStreamId, false);
         if (setStreamRatio) {
-            controller.windowUpdateRatio(ctx, newStreamId, ratio);
+            controller.windowUpdateRatio(ctx, stream, ratio);
         }
-        controller.initialStreamWindowSize(ctx, newStreamId, newDefaultWindowSize);
+        controller.incrementWindowSize(ctx, stream, delta);
         reset(frameWriter);
         try {
             int data1 = (int) (newDefaultWindowSize * ratio) + 1;
             int data2 = (int) (DEFAULT_WINDOW_SIZE * updateRatio) >> 1;
-            applyFlowControl(STREAM_ID, data2, 0, false);
+            receiveFlowControlledFrame(STREAM_ID, data2, 0, false);
-            applyFlowControl(newStreamId, data1, 0, false);
+            receiveFlowControlledFrame(newStreamId, data1, 0, false);
             verifyWindowUpdateNotSent(STREAM_ID);
             verifyWindowUpdateNotSent(newStreamId);
             verifyWindowUpdateNotSent(CONNECTION_STREAM_ID);
             assertEquals(DEFAULT_WINDOW_SIZE - data2, window(STREAM_ID));
             assertEquals(newDefaultWindowSize - data1, window(newStreamId));
             assertEquals(newDefaultWindowSize - data2 - data1, window(CONNECTION_STREAM_ID));
-            returnProcessedBytes(STREAM_ID, data2);
+            consumeBytes(STREAM_ID, data2);
-            returnProcessedBytes(newStreamId, data1);
+            consumeBytes(newStreamId, data1);
             verifyWindowUpdateNotSent(STREAM_ID);
             verifyWindowUpdateSent(newStreamId, data1);
             verifyWindowUpdateSent(CONNECTION_STREAM_ID, data1 + data2);
@@ -252,10 +253,11 @@ public class DefaultHttp2InboundFlowControllerTest {
         return initialSize - newWindowSize;
     }
 
-    private void applyFlowControl(int streamId, int dataSize, int padding, boolean endOfStream) throws Http2Exception {
+    private void receiveFlowControlledFrame(int streamId, int dataSize, int padding,
+            boolean endOfStream) throws Http2Exception {
         final ByteBuf buf = dummyData(dataSize);
         try {
-            controller.applyFlowControl(ctx, streamId, buf, padding, endOfStream);
+            controller.receiveFlowControlledFrame(ctx, stream(streamId), buf, padding, endOfStream);
         } finally {
             buf.release();
         }
@@ -267,8 +269,8 @@ public class DefaultHttp2InboundFlowControllerTest {
         return buffer;
     }
 
-    private void returnProcessedBytes(int streamId, int processedBytes) throws Http2Exception {
+    private void consumeBytes(int streamId, int numBytes) throws Http2Exception {
-        connection.requireStream(streamId).garbageCollector().returnProcessedBytes(ctx, processedBytes);
+        controller.consumeBytes(ctx, stream(streamId), numBytes);
     }
 
     private void verifyWindowUpdateSent(int streamId, int windowSizeIncrement) throws Http2Exception {
@@ -284,7 +286,11 @@ public class DefaultHttp2InboundFlowControllerTest {
                 any(ChannelPromise.class));
     }
 
-    private int window(int streamId) {
+    private int window(int streamId) throws Http2Exception {
-        return connection.stream(streamId).inboundFlow().window();
+        return controller.windowSize(stream(streamId));
+    }
+
+    private Http2Stream stream(int streamId) throws Http2Exception {
+        return connection.requireStream(streamId);
     }
 }

codec-http2/src/test/java/io/netty/handler/codec/http2/DefaultHttp2RemoteFlowControllerTest.java

@@ -19,8 +19,8 @@ import static io.netty.handler.codec.http2.Http2CodecUtil.CONNECTION_STREAM_ID;
 import static io.netty.handler.codec.http2.Http2CodecUtil.DEFAULT_PRIORITY_WEIGHT;
 import static io.netty.handler.codec.http2.Http2CodecUtil.DEFAULT_WINDOW_SIZE;
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.assertNotSame;
+import static org.junit.Assert.assertTrue;
 import static org.mockito.Matchers.any;
 import static org.mockito.Matchers.anyBoolean;
 import static org.mockito.Matchers.anyInt;
@@ -33,7 +33,6 @@ import io.netty.buffer.Unpooled;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.ChannelPromise;
-import io.netty.handler.codec.http2.DefaultHttp2OutboundFlowController.OutboundFlowState;
 import io.netty.handler.codec.http2.Http2FrameWriter.Configuration;
 import io.netty.util.collection.IntObjectHashMap;
 import io.netty.util.collection.IntObjectMap;
@@ -49,16 +48,16 @@ import org.mockito.Mockito;
 import org.mockito.MockitoAnnotations;
 
 /**
- * Tests for {@link DefaultHttp2OutboundFlowController}.
+ * Tests for {@link DefaultHttp2RemoteFlowController}.
  */
-public class DefaultHttp2OutboundFlowControllerTest {
+public class DefaultHttp2RemoteFlowControllerTest {
     private static final int STREAM_A = 1;
     private static final int STREAM_B = 3;
     private static final int STREAM_C = 5;
     private static final int STREAM_D = 7;
     private static final int STREAM_E = 9;
 
-    private DefaultHttp2OutboundFlowController controller;
+    private DefaultHttp2RemoteFlowController controller;
 
     @Mock
     private ByteBuf buffer;
@@ -87,7 +86,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
         when(ctx.newPromise()).thenReturn(promise);
 
         connection = new DefaultHttp2Connection(false);
-        controller = new DefaultHttp2OutboundFlowController(connection, frameWriter);
+        controller = new DefaultHttp2RemoteFlowController(connection, frameWriter);
 
         connection.local().createStream(STREAM_A, false);
         connection.local().createStream(STREAM_B, false);
@@ -101,7 +100,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
     @Test
     public void initialWindowSizeShouldOnlyChangeStreams() throws Http2Exception {
-        controller.initialOutboundWindowSize(0);
+        controller.initialWindowSize(0);
         assertEquals(DEFAULT_WINDOW_SIZE, window(CONNECTION_STREAM_ID));
         assertEquals(0, window(STREAM_A));
         assertEquals(0, window(STREAM_B));
@@ -111,7 +110,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
     @Test
     public void windowUpdateShouldChangeConnectionWindow() throws Http2Exception {
-        controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 100);
+        incrementWindowSize(CONNECTION_STREAM_ID, 100);
         assertEquals(DEFAULT_WINDOW_SIZE + 100, window(CONNECTION_STREAM_ID));
         assertEquals(DEFAULT_WINDOW_SIZE, window(STREAM_A));
         assertEquals(DEFAULT_WINDOW_SIZE, window(STREAM_B));
@@ -121,7 +120,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
     @Test
     public void windowUpdateShouldChangeStreamWindow() throws Http2Exception {
-        controller.updateOutboundWindowSize(STREAM_A, 100);
+        incrementWindowSize(STREAM_A, 100);
         assertEquals(DEFAULT_WINDOW_SIZE, window(CONNECTION_STREAM_ID));
         assertEquals(DEFAULT_WINDOW_SIZE + 100, window(STREAM_A));
         assertEquals(DEFAULT_WINDOW_SIZE, window(STREAM_B));
@@ -147,13 +146,14 @@ public class DefaultHttp2OutboundFlowControllerTest {
         final ByteBuf data = dummyData(5, 5);
         try {
             // Write one frame.
-            ChannelFuture future1 = controller.writeData(ctx, STREAM_A, data, 0, false, promise);
+            Http2Stream stream = stream(STREAM_A);
-            assertEquals(future1, controller.lastWriteForStream(STREAM_A));
+            ChannelFuture future1 = controller.sendFlowControlledFrame(ctx, stream, data, 0, false, promise);
+            assertEquals(future1, controller.lastFlowControlledFrameSent(stream));
 
             // Now write another and verify that the last write is updated.
-            ChannelFuture future2 = controller.writeData(ctx, STREAM_A, data, 0, false, promise2);
+            ChannelFuture future2 = controller.sendFlowControlledFrame(ctx, stream, data, 0, false, promise2);
             assertNotSame(future1, future2);
-            assertEquals(future2, controller.lastWriteForStream(STREAM_A));
+            assertEquals(future2, controller.lastFlowControlledFrameSent(stream));
         } finally {
             manualSafeRelease(data);
         }
@@ -200,7 +200,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
     @Test
     public void stalledStreamShouldQueueFrame() throws Http2Exception {
-        controller.initialOutboundWindowSize(0);
+        controller.initialWindowSize(0);
 
         final ByteBuf data = dummyData(10, 5);
         try {
@@ -214,7 +214,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
     @Test
     public void frameShouldSplit() throws Http2Exception {
-        controller.initialOutboundWindowSize(5);
+        controller.initialWindowSize(5);
 
         final ByteBuf data = dummyData(5, 5);
         try {
@@ -236,7 +236,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
     @Test
     public void frameShouldSplitPadding() throws Http2Exception {
-        controller.initialOutboundWindowSize(5);
+        controller.initialWindowSize(5);
 
         final ByteBuf data = dummyData(3, 7);
         try {
@@ -257,7 +257,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
     @Test
     public void emptyFrameShouldSplitPadding() throws Http2Exception {
-        controller.initialOutboundWindowSize(5);
+        controller.initialWindowSize(5);
 
         final ByteBuf data = dummyData(0, 10);
         try {
@@ -277,7 +277,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
     @Test
     public void windowUpdateShouldSendFrame() throws Http2Exception {
-        controller.initialOutboundWindowSize(10);
+        controller.initialWindowSize(10);
 
         final ByteBuf data = dummyData(10, 10);
         try {
@@ -285,7 +285,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyWrite(STREAM_A, data.slice(0, 10), 0);
 
             // Update the window and verify that the rest of the frame is written.
-            controller.updateOutboundWindowSize(STREAM_A, 10);
+            incrementWindowSize(STREAM_A, 10);
             verifyWrite(STREAM_A, Unpooled.EMPTY_BUFFER, 10);
             assertEquals(DEFAULT_WINDOW_SIZE - data.readableBytes(), window(CONNECTION_STREAM_ID));
             assertEquals(0, window(STREAM_A));
@@ -299,7 +299,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
     @Test
     public void initialWindowUpdateShouldSendFrame() throws Http2Exception {
-        controller.initialOutboundWindowSize(0);
+        controller.initialWindowSize(0);
 
         final ByteBuf data = dummyData(10, 0);
         try {
@@ -307,7 +307,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_A);
 
             // Verify that the entire frame was sent.
-            controller.initialOutboundWindowSize(10);
+            controller.initialWindowSize(10);
             ArgumentCaptor<ByteBuf> argument = ArgumentCaptor.forClass(ByteBuf.class);
             captureWrite(STREAM_A, argument, 0, false);
             final ByteBuf writtenBuf = argument.getValue();
@@ -321,7 +321,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
     @Test
     public void successiveSendsShouldNotInteract() throws Http2Exception {
         // Collapse the connection window to force queueing.
-        controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, -window(CONNECTION_STREAM_ID));
+        incrementWindowSize(CONNECTION_STREAM_ID, -window(CONNECTION_STREAM_ID));
         assertEquals(0, window(CONNECTION_STREAM_ID));
 
         ByteBuf data = dummyData(5, 5);
@@ -331,7 +331,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             send(STREAM_A, dataOnly.slice(), 5);
             verifyNoWrite(STREAM_A);
             verifyNoWrite(STREAM_B);
-            controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 8);
+            incrementWindowSize(CONNECTION_STREAM_ID, 8);
             ArgumentCaptor<ByteBuf> argument = ArgumentCaptor.forClass(ByteBuf.class);
             captureWrite(STREAM_A, argument, 3, false);
             ByteBuf writtenBuf = argument.getValue();
@@ -345,7 +345,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             send(STREAM_B, dataOnly.slice(), 5);
             verifyNoWrite(STREAM_A);
             verifyNoWrite(STREAM_B);
-            controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 12);
+            incrementWindowSize(CONNECTION_STREAM_ID, 12);
             assertEquals(0, window(CONNECTION_STREAM_ID));
 
             // Verify the rest of A is written.
@@ -368,7 +368,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
     public void negativeWindowShouldNotThrowException() throws Http2Exception {
         final int initWindow = 20;
         final int secondWindowSize = 10;
-        controller.initialOutboundWindowSize(initWindow);
+        controller.initialWindowSize(initWindow);
         Http2Stream streamA = connection.stream(STREAM_A);
 
         final ByteBuf data = dummyData(initWindow, 0);
@@ -379,8 +379,8 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyWrite(STREAM_A, data.slice(0, initWindow), 0);
 
             // Make the window size for stream A negative
-            controller.initialOutboundWindowSize(initWindow - secondWindowSize);
+            controller.initialWindowSize(initWindow - secondWindowSize);
-            assertEquals(-secondWindowSize, streamA.outboundFlow().window());
+            assertEquals(-secondWindowSize, controller.windowSize(streamA));
 
             // Queue up a write. It should not be written now because the window is negative
             resetFrameWriter();
@@ -388,18 +388,18 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_A);
 
             // Open the window size back up a bit (no send should happen)
-            controller.updateOutboundWindowSize(STREAM_A, 5);
+            incrementWindowSize(STREAM_A, 5);
-            assertEquals(-5, streamA.outboundFlow().window());
+            assertEquals(-5, controller.windowSize(streamA));
             verifyNoWrite(STREAM_A);
 
             // Open the window size back up a bit (no send should happen)
-            controller.updateOutboundWindowSize(STREAM_A, 5);
+            incrementWindowSize(STREAM_A, 5);
-            assertEquals(0, streamA.outboundFlow().window());
+            assertEquals(0, controller.windowSize(streamA));
             verifyNoWrite(STREAM_A);
 
             // Open the window size back up and allow the write to happen
-            controller.updateOutboundWindowSize(STREAM_A, 5);
+            incrementWindowSize(STREAM_A, 5);
-            assertEquals(0, streamA.outboundFlow().window());
+            assertEquals(0, controller.windowSize(streamA));
 
             // Verify that the entire frame was sent.
             ArgumentCaptor<ByteBuf> argument = ArgumentCaptor.forClass(ByteBuf.class);
@@ -415,7 +415,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
     @Test
     public void initialWindowUpdateShouldSendEmptyFrame() throws Http2Exception {
-        controller.initialOutboundWindowSize(0);
+        controller.initialWindowSize(0);
 
         // First send a frame that will get buffered.
         final ByteBuf data = dummyData(10, 0);
@@ -428,7 +428,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_A);
 
             // Re-expand the window and verify that both frames were sent.
-            controller.initialOutboundWindowSize(10);
+            controller.initialWindowSize(10);
 
             verifyWrite(STREAM_A, data.slice(), 0);
             verifyWrite(STREAM_A, Unpooled.EMPTY_BUFFER, 0);
@@ -439,7 +439,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
     @Test
     public void initialWindowUpdateShouldSendPartialFrame() throws Http2Exception {
-        controller.initialOutboundWindowSize(0);
+        controller.initialWindowSize(0);
 
         final ByteBuf data = dummyData(10, 0);
         try {
@@ -447,7 +447,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_A);
 
             // Verify that a partial frame of 5 was sent.
-            controller.initialOutboundWindowSize(5);
+            controller.initialWindowSize(5);
             ArgumentCaptor<ByteBuf> argument = ArgumentCaptor.forClass(ByteBuf.class);
             captureWrite(STREAM_A, argument, 0, false);
             ByteBuf writtenBuf = argument.getValue();
@@ -471,7 +471,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_A);
 
             // Verify that the entire frame was sent.
-            controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 10);
+            incrementWindowSize(CONNECTION_STREAM_ID, 10);
             assertEquals(0, window(CONNECTION_STREAM_ID));
             assertEquals(DEFAULT_WINDOW_SIZE - data.readableBytes(), window(STREAM_A));
             assertEquals(DEFAULT_WINDOW_SIZE, window(STREAM_B));
@@ -499,7 +499,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_A);
 
             // Verify that a partial frame of 5 was sent.
-            controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 5);
+            incrementWindowSize(CONNECTION_STREAM_ID, 5);
             assertEquals(0, window(CONNECTION_STREAM_ID));
             assertEquals(DEFAULT_WINDOW_SIZE - data.readableBytes(), window(STREAM_A));
             assertEquals(DEFAULT_WINDOW_SIZE, window(STREAM_B));
@@ -529,7 +529,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_A);
 
             // Verify that the entire frame was sent.
-            controller.updateOutboundWindowSize(STREAM_A, 10);
+            incrementWindowSize(STREAM_A, 10);
             assertEquals(DEFAULT_WINDOW_SIZE - data.readableBytes(), window(CONNECTION_STREAM_ID));
             assertEquals(0, window(STREAM_A));
             assertEquals(DEFAULT_WINDOW_SIZE, window(STREAM_B));
@@ -557,7 +557,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_A);
 
             // Verify that a partial frame of 5 was sent.
-            controller.updateOutboundWindowSize(STREAM_A, 5);
+            incrementWindowSize(STREAM_A, 5);
             assertEquals(DEFAULT_WINDOW_SIZE - data.readableBytes(), window(CONNECTION_STREAM_ID));
             assertEquals(0, window(STREAM_A));
             assertEquals(DEFAULT_WINDOW_SIZE, window(STREAM_B));
@@ -599,7 +599,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_B);
 
             // Open up the connection window.
-            controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 10);
+            incrementWindowSize(CONNECTION_STREAM_ID, 10);
             assertEquals(0, window(CONNECTION_STREAM_ID));
             assertEquals(DEFAULT_WINDOW_SIZE - 5, window(STREAM_A));
             assertEquals(DEFAULT_WINDOW_SIZE - 5, window(STREAM_B));
@@ -653,7 +653,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_D);
 
             // Verify that the entire frame was sent.
-            controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 10);
+            incrementWindowSize(CONNECTION_STREAM_ID, 10);
             assertEquals(0, window(CONNECTION_STREAM_ID));
             assertEquals(0, window(STREAM_A));
             assertEquals(DEFAULT_WINDOW_SIZE - 5, window(STREAM_B), 2);
@@ -713,7 +713,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_D);
 
             // Verify that the entire frame was sent.
-            controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 10);
+            incrementWindowSize(CONNECTION_STREAM_ID, 10);
             assertEquals(0, window(CONNECTION_STREAM_ID));
             assertEquals(DEFAULT_WINDOW_SIZE - 10, window(STREAM_A));
             assertEquals(0, window(STREAM_B));
@@ -766,7 +766,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_D);
 
             // Verify that the entire frame was sent.
-            controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 10);
+            incrementWindowSize(CONNECTION_STREAM_ID, 10);
             assertEquals(0, window(CONNECTION_STREAM_ID));
             assertEquals(DEFAULT_WINDOW_SIZE - 5, window(STREAM_A));
             assertEquals(0, window(STREAM_B));
@@ -840,7 +840,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             setPriority(STREAM_D, 0, DEFAULT_PRIORITY_WEIGHT, false);
 
             // Verify that the entire frame was sent.
-            controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 10);
+            incrementWindowSize(CONNECTION_STREAM_ID, 10);
             assertEquals(0, window(CONNECTION_STREAM_ID));
             assertEquals(DEFAULT_WINDOW_SIZE - 5, window(STREAM_A), 2);
             assertEquals(0, window(STREAM_B));
@@ -895,7 +895,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_D);
 
             // Allow 1000 bytes to be sent.
-            controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 1000);
+            incrementWindowSize(CONNECTION_STREAM_ID, 1000);
             final ArgumentCaptor<ByteBuf> captor = ArgumentCaptor.forClass(ByteBuf.class);
 
             captureWrite(STREAM_A, captor, 0, false);
@@ -973,7 +973,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
             assertEquals(0, captor.getValue().readableBytes());
 
             // Allow 1000 bytes to be sent.
-            controller.updateOutboundWindowSize(CONNECTION_STREAM_ID, 999);
+            incrementWindowSize(CONNECTION_STREAM_ID, 999);
             assertEquals(0, window(CONNECTION_STREAM_ID));
             assertEquals(DEFAULT_WINDOW_SIZE - 333, window(STREAM_A), 50);
             assertEquals(DEFAULT_WINDOW_SIZE - 333, window(STREAM_B), 50);
@@ -1038,18 +1038,17 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_C);
             verifyNoWrite(STREAM_D);
 
-            OutboundFlowState state = state(stream0);
+            assertEquals(calculateStreamSizeSum(streamSizes,
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_A, STREAM_B, STREAM_C, STREAM_D)),
+                            Arrays.asList(STREAM_A, STREAM_B, STREAM_C, STREAM_D)),
-                    state.streamableBytesForTree());
+                            streamableBytesForTree(stream0));
-            state = state(streamA);
             assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_A, STREAM_C, STREAM_D)),
-                    state.streamableBytesForTree());
+                    streamableBytesForTree(streamA));
-            state = state(streamB);
+            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_B)),
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_B)), state.streamableBytesForTree());
+                    streamableBytesForTree(streamB));
-            state = state(streamC);
+            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_C)),
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_C)), state.streamableBytesForTree());
+                    streamableBytesForTree(streamC));
-            state = state(streamD);
+            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_D)),
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_D)), state.streamableBytesForTree());
+                    streamableBytesForTree(streamD));
         } finally {
             manualSafeRelease(bufs);
         }
@@ -1108,19 +1107,18 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_D);
 
             streamB.setPriority(STREAM_A, DEFAULT_PRIORITY_WEIGHT, true);
-            OutboundFlowState state = state(stream0);
+            assertEquals(calculateStreamSizeSum(streamSizes,
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_A, STREAM_B, STREAM_C, STREAM_D)),
+                            Arrays.asList(STREAM_A, STREAM_B, STREAM_C, STREAM_D)),
-                    state.streamableBytesForTree());
+                            streamableBytesForTree(stream0));
-            state = state(streamA);
+            assertEquals(calculateStreamSizeSum(streamSizes,
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_A, STREAM_B, STREAM_C, STREAM_D)),
+                            Arrays.asList(STREAM_A, STREAM_B, STREAM_C, STREAM_D)),
-                    state.streamableBytesForTree());
+                            streamableBytesForTree(streamA));
-            state = state(streamB);
             assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_B, STREAM_C, STREAM_D)),
-                    state.streamableBytesForTree());
+                         streamableBytesForTree(streamB));
-            state = state(streamC);
+            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_C)),
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_C)), state.streamableBytesForTree());
+                    streamableBytesForTree(streamC));
-            state = state(streamD);
+            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_D)),
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_D)), state.streamableBytesForTree());
+                    streamableBytesForTree(streamD));
         } finally {
             manualSafeRelease(bufs);
         }
@@ -1185,23 +1183,20 @@ public class DefaultHttp2OutboundFlowControllerTest {
             verifyNoWrite(STREAM_D);
             verifyNoWrite(STREAM_E);
 
-            OutboundFlowState state = state(stream0);
+            assertEquals(calculateStreamSizeSum(streamSizes,
-            assertEquals(
-                    calculateStreamSizeSum(streamSizes,
                             Arrays.asList(STREAM_A, STREAM_B, STREAM_C, STREAM_D, STREAM_E)),
-                    state.streamableBytesForTree());
+                    streamableBytesForTree(stream0));
-            state = state(streamA);
+            assertEquals(calculateStreamSizeSum(streamSizes,
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_A, STREAM_E, STREAM_C, STREAM_D)),
+                            Arrays.asList(STREAM_A, STREAM_E, STREAM_C, STREAM_D)),
-                    state.streamableBytesForTree());
+                    streamableBytesForTree(streamA));
-            state = state(streamB);
+            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_B)),
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_B)), state.streamableBytesForTree());
+                    streamableBytesForTree(streamB));
-            state = state(streamC);
+            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_C)),
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_C)), state.streamableBytesForTree());
+                    streamableBytesForTree(streamC));
-            state = state(streamD);
+            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_D)),
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_D)), state.streamableBytesForTree());
+                    streamableBytesForTree(streamD));
-            state = state(streamE);
             assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_E, STREAM_C, STREAM_D)),
-                    state.streamableBytesForTree());
+                    streamableBytesForTree(streamE));
         } finally {
             manualSafeRelease(bufs);
         }
@@ -1257,26 +1252,20 @@ public class DefaultHttp2OutboundFlowControllerTest {
 
             streamA.close();
 
-            OutboundFlowState state = state(stream0);
             assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_B, STREAM_C, STREAM_D)),
-                    state.streamableBytesForTree());
+                    streamableBytesForTree(stream0));
-            state = state(streamA);
+            assertEquals(0, streamableBytesForTree(streamA));
-            assertEquals(0, state.streamableBytesForTree());
+            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_B)),
-            state = state(streamB);
+                    streamableBytesForTree(streamB));
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_B)), state.streamableBytesForTree());
+            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_C)),
-            state = state(streamC);
+                    streamableBytesForTree(streamC));
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_C)), state.streamableBytesForTree());
+            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_D)),
-            state = state(streamD);
+                    streamableBytesForTree(streamD));
-            assertEquals(calculateStreamSizeSum(streamSizes, Arrays.asList(STREAM_D)), state.streamableBytesForTree());
         } finally {
             manualSafeRelease(bufs);
         }
     }
 
-    private static OutboundFlowState state(Http2Stream stream) {
-        return (OutboundFlowState) stream.outboundFlow();
-    }
-
     private static int calculateStreamSizeSum(IntObjectMap<Integer> streamSizes, List<Integer> streamIds) {
         int sum = 0;
         for (int i = 0; i < streamIds.size(); ++i) {
@@ -1288,9 +1277,10 @@ public class DefaultHttp2OutboundFlowControllerTest {
         return sum;
     }
 
-    private void send(int streamId, ByteBuf data, int padding) {
+    private void send(int streamId, ByteBuf data, int padding) throws Http2Exception {
-        ChannelFuture future = controller.writeData(ctx, streamId, data, padding, false, promise);
+        Http2Stream stream = stream(streamId);
-        assertEquals(future, controller.lastWriteForStream(streamId));
+        ChannelFuture future = controller.sendFlowControlledFrame(ctx, stream, data, padding, false, promise);
+        assertEquals(future, controller.lastFlowControlledFrameSent(stream));
     }
 
     private void verifyWrite(int streamId, ByteBuf data, int padding) {
@@ -1302,8 +1292,10 @@ public class DefaultHttp2OutboundFlowControllerTest {
                 eq(promise));
     }
 
-    private void captureWrite(int streamId, ArgumentCaptor<ByteBuf> captor, int padding, boolean endStream) {
+    private void captureWrite(int streamId, ArgumentCaptor<ByteBuf> captor, int padding,
-        verify(frameWriter).writeData(eq(ctx), eq(streamId), captor.capture(), eq(padding), eq(endStream), eq(promise));
+            boolean endStream) {
+        verify(frameWriter).writeData(eq(ctx), eq(streamId), captor.capture(), eq(padding),
+                eq(endStream), eq(promise));
     }
 
     private void setPriority(int stream, int parent, int weight, boolean exclusive) throws Http2Exception {
@@ -1311,7 +1303,7 @@ public class DefaultHttp2OutboundFlowControllerTest {
     }
 
     private void exhaustStreamWindow(int streamId) throws Http2Exception {
-        controller.updateOutboundWindowSize(streamId, -window(streamId));
+        incrementWindowSize(streamId, -window(streamId));
     }
 
     private void resetFrameWriter() {
@@ -1321,8 +1313,20 @@ public class DefaultHttp2OutboundFlowControllerTest {
         when(frameWriterSizePolicy.maxFrameSize()).thenReturn(Integer.MAX_VALUE);
     }
 
-    private int window(int streamId) {
+    private int window(int streamId) throws Http2Exception {
-        return connection.stream(streamId).outboundFlow().window();
+        return controller.windowSize(stream(streamId));
+    }
+
+    private void incrementWindowSize(int streamId, int delta) throws Http2Exception {
+        controller.incrementWindowSize(ctx, stream(streamId), delta);
+    }
+
+    private int streamableBytesForTree(Http2Stream stream) throws Http2Exception {
+        return controller.streamableBytesForTree(stream);
+    }
+
+    private Http2Stream stream(int streamId) throws Http2Exception {
+        return connection.requireStream(streamId);
     }
 
     private static ByteBuf dummyData(int size, int padding) {

example/src/main/java/io/netty/example/http2/client/Http2ClientInitializer.java

@@ -28,8 +28,6 @@ import io.netty.handler.codec.http.HttpVersion;
 import io.netty.handler.codec.http2.DefaultHttp2Connection;
 import io.netty.handler.codec.http2.DefaultHttp2FrameReader;
 import io.netty.handler.codec.http2.DefaultHttp2FrameWriter;
-import io.netty.handler.codec.http2.DefaultHttp2InboundFlowController;
-import io.netty.handler.codec.http2.DefaultHttp2OutboundFlowController;
 import io.netty.handler.codec.http2.DelegatingDecompressorFrameListener;
 import io.netty.handler.codec.http2.Http2ClientUpgradeCodec;
 import io.netty.handler.codec.http2.Http2Connection;
@@ -68,8 +66,6 @@ public class Http2ClientInitializer extends ChannelInitializer<SocketChannel> {
         connectionHandler = new HttpToHttp2ConnectionHandler(connection,
                 frameReader(),
                 frameWriter,
-                new DefaultHttp2InboundFlowController(connection, frameWriter),
-                new DefaultHttp2OutboundFlowController(connection, frameWriter),
                 new DelegatingDecompressorFrameListener(connection,
                         new InboundHttp2ToHttpAdapter.Builder(connection)
                                 .maxContentLength(maxContentLength)

example/src/main/java/io/netty/example/http2/server/HelloWorldHttp2Handler.java

@@ -23,7 +23,6 @@ import static io.netty.util.internal.logging.InternalLogLevel.INFO;
 import io.netty.buffer.ByteBuf;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.handler.codec.AsciiString;
-import io.netty.handler.codec.http.HttpResponseStatus;
 import io.netty.handler.codec.http.HttpServerUpgradeHandler;
 import io.netty.handler.codec.http2.DefaultHttp2Connection;
 import io.netty.handler.codec.http2.DefaultHttp2FrameReader;