Support multiple variants of the SPDY protocol.

This behavior-free refactoring makes the first baby steps towards
supporting HTTP/2.0. It adds indirection on the framing layer so
we can frame either using SPDY/3's syntax or HTTP/2.0's.

mockwebserver/src/main/java/com/squareup/okhttp/mockwebserver/MockWebServer.java

@@ -70,12 +70,17 @@ import static com.squareup.okhttp.mockwebserver.SocketPolicy.FAIL_HANDSHAKE;
  */
 public final class MockWebServer {
   private static final byte[] NPN_PROTOCOLS = {
+      // TODO: support HTTP/2.0.
+      // 17, 'H', 'T', 'T', 'P', '-', 'd', 'r', 'a', 'f', 't', '-', '0', '4', '/', '2', '.', '0',
       6, 's', 'p', 'd', 'y', '/', '3',
       8, 'h', 't', 't', 'p', '/', '1', '.', '1'
   };
   private static final byte[] SPDY3 = new byte[] {
       's', 'p', 'd', 'y', '/', '3'
   };
+  private static final byte[] HTTP_20_DRAFT_04 = new byte[] {
+      'H', 'T', 'T', 'P', '-', 'd', 'r', 'a', 'f', 't', '-', '0', '4', '/', '2', '.', '0'
+  };
   private static final byte[] HTTP_11 = new byte[] {
       'h', 't', 't', 'p', '/', '1', '.', '1'
   };
@@ -322,6 +327,8 @@ public final class MockWebServer {
             byte[] selectedProtocol = Platform.get().getNpnSelectedProtocol(sslSocket);
             if (selectedProtocol == null || Arrays.equals(selectedProtocol, HTTP_11)) {
               transport = Transport.HTTP_11;
+            } else if (Arrays.equals(selectedProtocol, HTTP_20_DRAFT_04)) {
+              transport = Transport.HTTP_20_DRAFT_04;
             } else if (Arrays.equals(selectedProtocol, SPDY3)) {
               transport = Transport.SPDY_3;
             } else {
@@ -334,13 +341,19 @@ public final class MockWebServer {
           socket = raw;
         }
 
-        if (transport == Transport.SPDY_3) {
+        if (transport == Transport.SPDY_3 || transport == Transport.HTTP_20_DRAFT_04) {
           SpdySocketHandler spdySocketHandler = new SpdySocketHandler(socket);
-          SpdyConnection spdyConnection = new SpdyConnection.Builder(false, socket)
-              .handler(spdySocketHandler)
-              .build();
+          SpdyConnection.Builder builder = new SpdyConnection.Builder(false, socket)
+              .handler(spdySocketHandler);
+          if (transport == Transport.SPDY_3) {
+            builder.spdy3();
+          } else {
+            builder.http20Draft04();
+          }
+          SpdyConnection spdyConnection = builder.build();
           openSpdyConnections.put(spdyConnection, Boolean.TRUE);
           openClientSockets.remove(socket);
+          spdyConnection.sendConnectionHeader();
           return;
         }
 
@@ -699,6 +712,6 @@ public final class MockWebServer {
   }
 
   enum Transport {
-    HTTP_11, SPDY_3
+    HTTP_11, SPDY_3, HTTP_20_DRAFT_04
   }
 }

okhttp-protocols/src/main/java/com/squareup/okhttp/internal/spdy/Http20Draft04.java

@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2013 Square, Inc.
+ *
+ * Licensed 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 com.squareup.okhttp.internal.spdy;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.List;
+
+final class Http20Draft04 implements Variant {
+  @Override public SpdyReader newReader(InputStream in) {
+    return new Reader(in);
+  }
+
+  @Override public SpdyWriter newWriter(OutputStream out) {
+    return new Writer(out);
+  }
+
+  static final class Reader implements SpdyReader {
+    private final DataInputStream in;
+
+    Reader(InputStream in) {
+      this.in = new DataInputStream(in);
+    }
+
+    @Override public boolean nextFrame(Handler handler) throws IOException {
+      return false;
+    }
+
+    @Override public void close() throws IOException {
+      in.close();
+    }
+  }
+
+  static final class Writer implements SpdyWriter {
+    private final DataOutputStream out;
+
+    Writer(OutputStream out) {
+      this.out = new DataOutputStream(out);
+    }
+
+    @Override public synchronized void writeFrame(byte[] data, int offset, int length)
+        throws IOException {
+      // TODO: this method no longer makes sense; the raw frame can't support all variants!
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public synchronized void flush() throws IOException {
+      out.flush();
+    }
+
+    @Override public synchronized void connectionHeader() {
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public synchronized void synStream(int flags, int streamId, int associatedStreamId,
+        int priority, int slot, List<String> nameValueBlock) throws IOException {
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public synchronized void synReply(int flags, int streamId,
+        List<String> nameValueBlock) throws IOException {
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public synchronized void headers(int flags, int streamId, List<String> nameValueBlock)
+        throws IOException {
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public synchronized void rstStream(int streamId, int statusCode) throws IOException {
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public synchronized void data(int flags, int streamId, byte[] data)
+        throws IOException {
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public synchronized void settings(int flags, Settings settings) throws IOException {
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public synchronized void noop() throws IOException {
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public synchronized void ping(int flags, int id) throws IOException {
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public synchronized void goAway(int flags, int lastGoodStreamId, int statusCode)
+        throws IOException {
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public synchronized void windowUpdate(int streamId, int deltaWindowSize)
+        throws IOException {
+      throw new UnsupportedOperationException("TODO");
+    }
+
+    @Override public void close() throws IOException {
+      out.close();
+    }
+  }
+}

okhttp-protocols/src/main/java/com/squareup/okhttp/internal/spdy/Spdy3.java

@@ -0,0 +1,487 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed 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 com.squareup.okhttp.internal.spdy;
+
+import com.squareup.okhttp.internal.Platform;
+import com.squareup.okhttp.internal.Util;
+import java.io.ByteArrayOutputStream;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.UnsupportedEncodingException;
+import java.net.ProtocolException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.logging.Logger;
+import java.util.zip.DataFormatException;
+import java.util.zip.Deflater;
+import java.util.zip.Inflater;
+import java.util.zip.InflaterInputStream;
+
+final class Spdy3 implements Variant {
+  static final byte[] DICTIONARY;
+  static {
+    try {
+      DICTIONARY = ("\u0000\u0000\u0000\u0007options\u0000\u0000\u0000\u0004hea"
+          + "d\u0000\u0000\u0000\u0004post\u0000\u0000\u0000\u0003put\u0000\u0000\u0000\u0006dele"
+          + "te\u0000\u0000\u0000\u0005trace\u0000\u0000\u0000\u0006accept\u0000\u0000\u0000"
+          + "\u000Eaccept-charset\u0000\u0000\u0000\u000Faccept-encoding\u0000\u0000\u0000\u000Fa"
+          + "ccept-language\u0000\u0000\u0000\raccept-ranges\u0000\u0000\u0000\u0003age\u0000"
+          + "\u0000\u0000\u0005allow\u0000\u0000\u0000\rauthorization\u0000\u0000\u0000\rcache-co"
+          + "ntrol\u0000\u0000\u0000\nconnection\u0000\u0000\u0000\fcontent-base\u0000\u0000"
+          + "\u0000\u0010content-encoding\u0000\u0000\u0000\u0010content-language\u0000\u0000"
+          + "\u0000\u000Econtent-length\u0000\u0000\u0000\u0010content-location\u0000\u0000\u0000"
+          + "\u000Bcontent-md5\u0000\u0000\u0000\rcontent-range\u0000\u0000\u0000\fcontent-type"
+          + "\u0000\u0000\u0000\u0004date\u0000\u0000\u0000\u0004etag\u0000\u0000\u0000\u0006expe"
+          + "ct\u0000\u0000\u0000\u0007expires\u0000\u0000\u0000\u0004from\u0000\u0000\u0000"
+          + "\u0004host\u0000\u0000\u0000\bif-match\u0000\u0000\u0000\u0011if-modified-since"
+          + "\u0000\u0000\u0000\rif-none-match\u0000\u0000\u0000\bif-range\u0000\u0000\u0000"
+          + "\u0013if-unmodified-since\u0000\u0000\u0000\rlast-modified\u0000\u0000\u0000\blocati"
+          + "on\u0000\u0000\u0000\fmax-forwards\u0000\u0000\u0000\u0006pragma\u0000\u0000\u0000"
+          + "\u0012proxy-authenticate\u0000\u0000\u0000\u0013proxy-authorization\u0000\u0000"
+          + "\u0000\u0005range\u0000\u0000\u0000\u0007referer\u0000\u0000\u0000\u000Bretry-after"
+          + "\u0000\u0000\u0000\u0006server\u0000\u0000\u0000\u0002te\u0000\u0000\u0000\u0007trai"
+          + "ler\u0000\u0000\u0000\u0011transfer-encoding\u0000\u0000\u0000\u0007upgrade\u0000"
+          + "\u0000\u0000\nuser-agent\u0000\u0000\u0000\u0004vary\u0000\u0000\u0000\u0003via"
+          + "\u0000\u0000\u0000\u0007warning\u0000\u0000\u0000\u0010www-authenticate\u0000\u0000"
+          + "\u0000\u0006method\u0000\u0000\u0000\u0003get\u0000\u0000\u0000\u0006status\u0000"
+          + "\u0000\u0000\u0006200 OK\u0000\u0000\u0000\u0007version\u0000\u0000\u0000\bHTTP/1.1"
+          + "\u0000\u0000\u0000\u0003url\u0000\u0000\u0000\u0006public\u0000\u0000\u0000\nset-coo"
+          + "kie\u0000\u0000\u0000\nkeep-alive\u0000\u0000\u0000\u0006origin100101201202205206300"
+          + "302303304305306307402405406407408409410411412413414415416417502504505203 Non-Authori"
+          + "tative Information204 No Content301 Moved Permanently400 Bad Request401 Unauthorized"
+          + "403 Forbidden404 Not Found500 Internal Server Error501 Not Implemented503 Service Un"
+          + "availableJan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec 00:00:00 Mon, Tue, Wed, Th"
+          + "u, Fri, Sat, Sun, GMTchunked,text/html,image/png,image/jpg,image/gif,application/xml"
+          + ",application/xhtml+xml,text/plain,text/javascript,publicprivatemax-age=gzip,deflate,"
+          + "sdchcharset=utf-8charset=iso-8859-1,utf-,*,enq=0.").getBytes(Util.UTF_8.name());
+    } catch (UnsupportedEncodingException e) {
+      throw new AssertionError();
+    }
+  }
+
+  @Override public SpdyReader newReader(InputStream in) {
+    return new Reader(in);
+  }
+
+  @Override public SpdyWriter newWriter(OutputStream out) {
+    return new Writer(out);
+  }
+
+  /** Read spdy/3 frames. */
+  static final class Reader implements SpdyReader {
+    private final DataInputStream in;
+    private final DataInputStream nameValueBlockIn;
+    private int compressedLimit;
+
+    Reader(InputStream in) {
+      this.in = new DataInputStream(in);
+      this.nameValueBlockIn = newNameValueBlockStream();
+    }
+
+    /**
+     * Send the next frame to {@code handler}. Returns true unless there are no
+     * more frames on the stream.
+     */
+    @Override public boolean nextFrame(Handler handler) throws IOException {
+      int w1;
+      try {
+        w1 = in.readInt();
+      } catch (IOException e) {
+        return false; // This might be a normal socket close.
+      }
+      int w2 = in.readInt();
+
+      boolean control = (w1 & 0x80000000) != 0;
+      int flags = (w2 & 0xff000000) >>> 24;
+      int length = (w2 & 0xffffff);
+
+      if (control) {
+        int version = (w1 & 0x7fff0000) >>> 16;
+        int type = (w1 & 0xffff);
+
+        if (version != 3) {
+          throw new ProtocolException("version != 3: " + version);
+        }
+
+        switch (type) {
+          case SpdyConnection.TYPE_SYN_STREAM:
+            readSynStream(handler, flags, length);
+            return true;
+
+          case SpdyConnection.TYPE_SYN_REPLY:
+            readSynReply(handler, flags, length);
+            return true;
+
+          case SpdyConnection.TYPE_RST_STREAM:
+            readRstStream(handler, flags, length);
+            return true;
+
+          case SpdyConnection.TYPE_SETTINGS:
+            readSettings(handler, flags, length);
+            return true;
+
+          case SpdyConnection.TYPE_NOOP:
+            if (length != 0) throw ioException("TYPE_NOOP length: %d != 0", length);
+            handler.noop();
+            return true;
+
+          case SpdyConnection.TYPE_PING:
+            readPing(handler, flags, length);
+            return true;
+
+          case SpdyConnection.TYPE_GOAWAY:
+            readGoAway(handler, flags, length);
+            return true;
+
+          case SpdyConnection.TYPE_HEADERS:
+            readHeaders(handler, flags, length);
+            return true;
+
+          case SpdyConnection.TYPE_WINDOW_UPDATE:
+            readWindowUpdate(handler, flags, length);
+            return true;
+
+          case SpdyConnection.TYPE_CREDENTIAL:
+            Util.skipByReading(in, length);
+            throw new UnsupportedOperationException("TODO"); // TODO: implement
+
+          default:
+            throw new IOException("Unexpected frame");
+        }
+      } else {
+        int streamId = w1 & 0x7fffffff;
+        handler.data(flags, streamId, in, length);
+        return true;
+      }
+    }
+
+    private void readSynStream(Handler handler, int flags, int length) throws IOException {
+      int w1 = in.readInt();
+      int w2 = in.readInt();
+      int s3 = in.readShort();
+      int streamId = w1 & 0x7fffffff;
+      int associatedStreamId = w2 & 0x7fffffff;
+      int priority = (s3 & 0xe000) >>> 13;
+      int slot = s3 & 0xff;
+      List<String> nameValueBlock = readNameValueBlock(length - 10);
+      handler.synStream(flags, streamId, associatedStreamId, priority, slot, nameValueBlock);
+    }
+
+    private void readSynReply(Handler handler, int flags, int length) throws IOException {
+      int w1 = in.readInt();
+      int streamId = w1 & 0x7fffffff;
+      List<String> nameValueBlock = readNameValueBlock(length - 4);
+      handler.synReply(flags, streamId, nameValueBlock);
+    }
+
+    private void readRstStream(Handler handler, int flags, int length) throws IOException {
+      if (length != 8) throw ioException("TYPE_RST_STREAM length: %d != 8", length);
+      int streamId = in.readInt() & 0x7fffffff;
+      int statusCode = in.readInt();
+      handler.rstStream(flags, streamId, statusCode);
+    }
+
+    private void readHeaders(Handler handler, int flags, int length) throws IOException {
+      int w1 = in.readInt();
+      int streamId = w1 & 0x7fffffff;
+      List<String> nameValueBlock = readNameValueBlock(length - 4);
+      handler.headers(flags, streamId, nameValueBlock);
+    }
+
+    private void readWindowUpdate(Handler handler, int flags, int length) throws IOException {
+      if (length != 8) throw ioException("TYPE_WINDOW_UPDATE length: %d != 8", length);
+      int w1 = in.readInt();
+      int w2 = in.readInt();
+      int streamId = w1 & 0x7fffffff;
+      int deltaWindowSize = w2 & 0x7fffffff;
+      handler.windowUpdate(flags, streamId, deltaWindowSize);
+    }
+
+    private DataInputStream newNameValueBlockStream() {
+      // Limit the inflater input stream to only those bytes in the Name/Value block.
+      final InputStream throttleStream = new InputStream() {
+        @Override public int read() throws IOException {
+          return Util.readSingleByte(this);
+        }
+
+        @Override public int read(byte[] buffer, int offset, int byteCount) throws IOException {
+          byteCount = Math.min(byteCount, compressedLimit);
+          int consumed = in.read(buffer, offset, byteCount);
+          compressedLimit -= consumed;
+          return consumed;
+        }
+
+        @Override public void close() throws IOException {
+          in.close();
+        }
+      };
+
+      // Subclass inflater to install a dictionary when it's needed.
+      Inflater inflater = new Inflater() {
+        @Override public int inflate(byte[] buffer, int offset, int count)
+            throws DataFormatException {
+          int result = super.inflate(buffer, offset, count);
+          if (result == 0 && needsDictionary()) {
+            setDictionary(DICTIONARY);
+            result = super.inflate(buffer, offset, count);
+          }
+          return result;
+        }
+      };
+
+      return new DataInputStream(new InflaterInputStream(throttleStream, inflater));
+    }
+
+    private List<String> readNameValueBlock(int length) throws IOException {
+      this.compressedLimit += length;
+      try {
+        int numberOfPairs = nameValueBlockIn.readInt();
+        if (numberOfPairs < 0) {
+          Logger.getLogger(getClass().getName()).warning("numberOfPairs < 0: " + numberOfPairs);
+          throw ioException("numberOfPairs < 0");
+        }
+        List<String> entries = new ArrayList<String>(numberOfPairs * 2);
+        for (int i = 0; i < numberOfPairs; i++) {
+          String name = readString();
+          String values = readString();
+          if (name.length() == 0) throw ioException("name.length == 0");
+          if (values.length() == 0) throw ioException("values.length == 0");
+          entries.add(name);
+          entries.add(values);
+        }
+
+        if (compressedLimit != 0) {
+          Logger.getLogger(getClass().getName()).warning("compressedLimit > 0: " + compressedLimit);
+        }
+
+        return entries;
+      } catch (DataFormatException e) {
+        throw new IOException(e.getMessage());
+      }
+    }
+
+    private String readString() throws DataFormatException, IOException {
+      int length = nameValueBlockIn.readInt();
+      byte[] bytes = new byte[length];
+      Util.readFully(nameValueBlockIn, bytes);
+      return new String(bytes, 0, length, "UTF-8");
+    }
+
+    private void readPing(Handler handler, int flags, int length) throws IOException {
+      if (length != 4) throw ioException("TYPE_PING length: %d != 4", length);
+      int id = in.readInt();
+      handler.ping(flags, id);
+    }
+
+    private void readGoAway(Handler handler, int flags, int length) throws IOException {
+      if (length != 8) throw ioException("TYPE_GOAWAY length: %d != 8", length);
+      int lastGoodStreamId = in.readInt() & 0x7fffffff;
+      int statusCode = in.readInt();
+      handler.goAway(flags, lastGoodStreamId, statusCode);
+    }
+
+    private void readSettings(Handler handler, int flags, int length) throws IOException {
+      int numberOfEntries = in.readInt();
+      if (length != 4 + 8 * numberOfEntries) {
+        throw ioException("TYPE_SETTINGS length: %d != 4 + 8 * %d", length, numberOfEntries);
+      }
+      Settings settings = new Settings();
+      for (int i = 0; i < numberOfEntries; i++) {
+        int w1 = in.readInt();
+        int value = in.readInt();
+        int idFlags = (w1 & 0xff000000) >>> 24;
+        int id = w1 & 0xffffff;
+        settings.set(id, idFlags, value);
+      }
+      handler.settings(flags, settings);
+    }
+
+    private static IOException ioException(String message, Object... args) throws IOException {
+      throw new IOException(String.format(message, args));
+    }
+
+    @Override public void close() throws IOException {
+      Util.closeAll(in, nameValueBlockIn);
+    }
+  }
+
+  /** Write spdy/3 frames. */
+  static final class Writer implements SpdyWriter {
+    private final DataOutputStream out;
+    private final ByteArrayOutputStream nameValueBlockBuffer;
+    private final DataOutputStream nameValueBlockOut;
+
+    Writer(OutputStream out) {
+      this.out = new DataOutputStream(out);
+
+      Deflater deflater = new Deflater();
+      deflater.setDictionary(DICTIONARY);
+      nameValueBlockBuffer = new ByteArrayOutputStream();
+      nameValueBlockOut = new DataOutputStream(
+          Platform.get().newDeflaterOutputStream(nameValueBlockBuffer, deflater, true));
+    }
+
+    @Override public void connectionHeader() {
+      // Do nothing: no connection header for SPDY/3.
+    }
+
+    @Override public synchronized void writeFrame(byte[] data, int offset, int length)
+        throws IOException {
+      out.write(data, offset, length);
+    }
+
+    @Override public synchronized void flush() throws IOException {
+      out.flush();
+    }
+
+    @Override public synchronized void synStream(int flags, int streamId, int associatedStreamId,
+        int priority, int slot, List<String> nameValueBlock) throws IOException {
+      writeNameValueBlockToBuffer(nameValueBlock);
+      int length = 10 + nameValueBlockBuffer.size();
+      int type = SpdyConnection.TYPE_SYN_STREAM;
+
+      int unused = 0;
+      out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
+      out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
+      out.writeInt(streamId & 0x7fffffff);
+      out.writeInt(associatedStreamId & 0x7fffffff);
+      out.writeShort((priority & 0x7) << 13 | (unused & 0x1f) << 8 | (slot & 0xff));
+      nameValueBlockBuffer.writeTo(out);
+      out.flush();
+    }
+
+    @Override public synchronized void synReply(
+        int flags, int streamId, List<String> nameValueBlock) throws IOException {
+      writeNameValueBlockToBuffer(nameValueBlock);
+      int type = SpdyConnection.TYPE_SYN_REPLY;
+      int length = nameValueBlockBuffer.size() + 4;
+
+      out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
+      out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
+      out.writeInt(streamId & 0x7fffffff);
+      nameValueBlockBuffer.writeTo(out);
+      out.flush();
+    }
+
+    @Override public synchronized void headers(int flags, int streamId, List<String> nameValueBlock)
+        throws IOException {
+      writeNameValueBlockToBuffer(nameValueBlock);
+      int type = SpdyConnection.TYPE_HEADERS;
+      int length = nameValueBlockBuffer.size() + 4;
+
+      out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
+      out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
+      out.writeInt(streamId & 0x7fffffff);
+      nameValueBlockBuffer.writeTo(out);
+      out.flush();
+    }
+
+    @Override public synchronized void rstStream(int streamId, int statusCode) throws IOException {
+      int flags = 0;
+      int type = SpdyConnection.TYPE_RST_STREAM;
+      int length = 8;
+      out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
+      out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
+      out.writeInt(streamId & 0x7fffffff);
+      out.writeInt(statusCode);
+      out.flush();
+    }
+
+    @Override public synchronized void data(int flags, int streamId, byte[] data)
+        throws IOException {
+      int length = data.length;
+      out.writeInt(streamId & 0x7fffffff);
+      out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
+      out.write(data);
+      out.flush();
+    }
+
+    private void writeNameValueBlockToBuffer(List<String> nameValueBlock) throws IOException {
+      nameValueBlockBuffer.reset();
+      int numberOfPairs = nameValueBlock.size() / 2;
+      nameValueBlockOut.writeInt(numberOfPairs);
+      for (String s : nameValueBlock) {
+        nameValueBlockOut.writeInt(s.length());
+        nameValueBlockOut.write(s.getBytes("UTF-8"));
+      }
+      nameValueBlockOut.flush();
+    }
+
+    @Override public synchronized void settings(int flags, Settings settings) throws IOException {
+      int type = SpdyConnection.TYPE_SETTINGS;
+      int size = settings.size();
+      int length = 4 + size * 8;
+      out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
+      out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
+      out.writeInt(size);
+      for (int i = 0; i <= Settings.COUNT; i++) {
+        if (!settings.isSet(i)) continue;
+        int settingsFlags = settings.flags(i);
+        out.writeInt((settingsFlags & 0xff) << 24 | (i & 0xffffff));
+        out.writeInt(settings.get(i));
+      }
+      out.flush();
+    }
+
+    @Override public synchronized void noop() throws IOException {
+      int type = SpdyConnection.TYPE_NOOP;
+      int length = 0;
+      int flags = 0;
+      out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
+      out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
+      out.flush();
+    }
+
+    @Override public synchronized void ping(int flags, int id) throws IOException {
+      int type = SpdyConnection.TYPE_PING;
+      int length = 4;
+      out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
+      out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
+      out.writeInt(id);
+      out.flush();
+    }
+
+    @Override public synchronized void goAway(int flags, int lastGoodStreamId, int statusCode)
+        throws IOException {
+      int type = SpdyConnection.TYPE_GOAWAY;
+      int length = 8;
+      out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
+      out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
+      out.writeInt(lastGoodStreamId);
+      out.writeInt(statusCode);
+      out.flush();
+    }
+
+    @Override public synchronized void windowUpdate(int streamId, int deltaWindowSize)
+        throws IOException {
+      int type = SpdyConnection.TYPE_WINDOW_UPDATE;
+      int flags = 0;
+      int length = 8;
+      out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
+      out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
+      out.writeInt(streamId);
+      out.writeInt(deltaWindowSize);
+      out.flush();
+    }
+
+    @Override public void close() throws IOException {
+      Util.closeAll(out, nameValueBlockOut);
+    }
+  }
+}

okhttp-protocols/src/main/java/com/squareup/okhttp/internal/spdy/SpdyConnection.java

@@ -79,6 +79,9 @@ public final class SpdyConnection implements Closeable {
       Integer.MAX_VALUE, 60, TimeUnit.SECONDS, new SynchronousQueue<Runnable>(),
       Util.daemonThreadFactory("OkHttp SpdyConnection"));
 
+  /** The protocol variant, like SPDY/3 or HTTP-draft-04/2.0. */
+  final Variant variant;
+
   /** True if this peer initiated the connection. */
   final boolean client;
 
@@ -105,10 +108,11 @@ public final class SpdyConnection implements Closeable {
   Settings settings;
 
   private SpdyConnection(Builder builder) {
+    variant = builder.variant;
     client = builder.client;
     handler = builder.handler;
-    spdyReader = new SpdyReader(builder.in);
-    spdyWriter = new SpdyWriter(builder.out);
+    spdyReader = variant.newReader(builder.in);
+    spdyWriter = variant.newWriter(builder.out);
     nextStreamId = builder.client ? 1 : 2;
     nextPingId = builder.client ? 1 : 2;
 
@@ -192,11 +196,8 @@ public final class SpdyConnection implements Closeable {
     spdyWriter.synReply(flags, streamId, alternating);
   }
 
-  /** Writes a complete data frame. */
   void writeFrame(byte[] bytes, int offset, int length) throws IOException {
-    synchronized (spdyWriter) {
-      spdyWriter.out.write(bytes, offset, length);
-    }
+    spdyWriter.writeFrame(bytes, offset, length);
   }
 
   void writeSynResetLater(final int streamId, final int statusCode) {
@@ -278,9 +279,7 @@ public final class SpdyConnection implements Closeable {
   }
 
   public void flush() throws IOException {
-    synchronized (spdyWriter) {
-      spdyWriter.out.flush();
-    }
+    spdyWriter.flush();
   }
 
   /**
@@ -368,12 +367,21 @@ public final class SpdyConnection implements Closeable {
     if (thrown != null) throw thrown;
   }
 
+  /**
+   * Sends a connection header if the current variant requires it. This should
+   * be called after {@link Builder#build} for all new connections.
+   */
+  public void sendConnectionHeader() {
+    spdyWriter.connectionHeader();
+  }
+
   public static class Builder {
     private String hostName;
     private InputStream in;
     private OutputStream out;
     private IncomingStreamHandler handler = IncomingStreamHandler.REFUSE_INCOMING_STREAMS;
-    public boolean client;
+    private Variant variant = Variant.SPDY3;
+    private boolean client;
 
     public Builder(boolean client, Socket socket) throws IOException {
       this("", client, socket.getInputStream(), socket.getOutputStream());
@@ -407,6 +415,16 @@ public final class SpdyConnection implements Closeable {
       return this;
     }
 
+    public Builder spdy3() {
+      this.variant = Variant.SPDY3;
+      return this;
+    }
+
+    public Builder http20Draft04() {
+      this.variant = Variant.HTTP_20_DRAFT_04;
+      return this;
+    }
+
     public SpdyConnection build() {
       return new SpdyConnection(this);
     }

okhttp-protocols/src/main/java/com/squareup/okhttp/internal/spdy/SpdyReader.java

@@ -16,304 +16,19 @@
 
 package com.squareup.okhttp.internal.spdy;
 
-import com.squareup.okhttp.internal.Util;
 import java.io.Closeable;
-import java.io.DataInputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.io.UnsupportedEncodingException;
-import java.net.ProtocolException;
-import java.util.ArrayList;
 import java.util.List;
-import java.util.logging.Logger;
-import java.util.zip.DataFormatException;
-import java.util.zip.Inflater;
-import java.util.zip.InflaterInputStream;
 
-/** Read spdy/3 frames. */
-final class SpdyReader implements Closeable {
-  static final byte[] DICTIONARY;
-  static {
-    try {
-      DICTIONARY = ("\u0000\u0000\u0000\u0007options\u0000\u0000\u0000\u0004hea"
-          + "d\u0000\u0000\u0000\u0004post\u0000\u0000\u0000\u0003put\u0000\u0000\u0000\u0006dele"
-          + "te\u0000\u0000\u0000\u0005trace\u0000\u0000\u0000\u0006accept\u0000\u0000\u0000"
-          + "\u000Eaccept-charset\u0000\u0000\u0000\u000Faccept-encoding\u0000\u0000\u0000\u000Fa"
-          + "ccept-language\u0000\u0000\u0000\raccept-ranges\u0000\u0000\u0000\u0003age\u0000"
-          + "\u0000\u0000\u0005allow\u0000\u0000\u0000\rauthorization\u0000\u0000\u0000\rcache-co"
-          + "ntrol\u0000\u0000\u0000\nconnection\u0000\u0000\u0000\fcontent-base\u0000\u0000"
-          + "\u0000\u0010content-encoding\u0000\u0000\u0000\u0010content-language\u0000\u0000"
-          + "\u0000\u000Econtent-length\u0000\u0000\u0000\u0010content-location\u0000\u0000\u0000"
-          + "\u000Bcontent-md5\u0000\u0000\u0000\rcontent-range\u0000\u0000\u0000\fcontent-type"
-          + "\u0000\u0000\u0000\u0004date\u0000\u0000\u0000\u0004etag\u0000\u0000\u0000\u0006expe"
-          + "ct\u0000\u0000\u0000\u0007expires\u0000\u0000\u0000\u0004from\u0000\u0000\u0000"
-          + "\u0004host\u0000\u0000\u0000\bif-match\u0000\u0000\u0000\u0011if-modified-since"
-          + "\u0000\u0000\u0000\rif-none-match\u0000\u0000\u0000\bif-range\u0000\u0000\u0000"
-          + "\u0013if-unmodified-since\u0000\u0000\u0000\rlast-modified\u0000\u0000\u0000\blocati"
-          + "on\u0000\u0000\u0000\fmax-forwards\u0000\u0000\u0000\u0006pragma\u0000\u0000\u0000"
-          + "\u0012proxy-authenticate\u0000\u0000\u0000\u0013proxy-authorization\u0000\u0000"
-          + "\u0000\u0005range\u0000\u0000\u0000\u0007referer\u0000\u0000\u0000\u000Bretry-after"
-          + "\u0000\u0000\u0000\u0006server\u0000\u0000\u0000\u0002te\u0000\u0000\u0000\u0007trai"
-          + "ler\u0000\u0000\u0000\u0011transfer-encoding\u0000\u0000\u0000\u0007upgrade\u0000"
-          + "\u0000\u0000\nuser-agent\u0000\u0000\u0000\u0004vary\u0000\u0000\u0000\u0003via"
-          + "\u0000\u0000\u0000\u0007warning\u0000\u0000\u0000\u0010www-authenticate\u0000\u0000"
-          + "\u0000\u0006method\u0000\u0000\u0000\u0003get\u0000\u0000\u0000\u0006status\u0000"
-          + "\u0000\u0000\u0006200 OK\u0000\u0000\u0000\u0007version\u0000\u0000\u0000\bHTTP/1.1"
-          + "\u0000\u0000\u0000\u0003url\u0000\u0000\u0000\u0006public\u0000\u0000\u0000\nset-coo"
-          + "kie\u0000\u0000\u0000\nkeep-alive\u0000\u0000\u0000\u0006origin100101201202205206300"
-          + "302303304305306307402405406407408409410411412413414415416417502504505203 Non-Authori"
-          + "tative Information204 No Content301 Moved Permanently400 Bad Request401 Unauthorized"
-          + "403 Forbidden404 Not Found500 Internal Server Error501 Not Implemented503 Service Un"
-          + "availableJan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec 00:00:00 Mon, Tue, Wed, Th"
-          + "u, Fri, Sat, Sun, GMTchunked,text/html,image/png,image/jpg,image/gif,application/xml"
-          + ",application/xhtml+xml,text/plain,text/javascript,publicprivatemax-age=gzip,deflate,"
-          + "sdchcharset=utf-8charset=iso-8859-1,utf-,*,enq=0.").getBytes(Util.UTF_8.name());
-    } catch (UnsupportedEncodingException e) {
-      throw new AssertionError();
-    }
-  }
-
-  private final DataInputStream in;
-  private final DataInputStream nameValueBlockIn;
-  private int compressedLimit;
-
-  SpdyReader(InputStream in) {
-    this.in = new DataInputStream(in);
-    this.nameValueBlockIn = newNameValueBlockStream();
-  }
-
-  /**
-   * Send the next frame to {@code handler}. Returns true unless there are no
-   * more frames on the stream.
-   */
-  public boolean nextFrame(Handler handler) throws IOException {
-    int w1;
-    try {
-      w1 = in.readInt();
-    } catch (IOException e) {
-      return false; // This might be a normal socket close.
-    }
-    int w2 = in.readInt();
-
-    boolean control = (w1 & 0x80000000) != 0;
-    int flags = (w2 & 0xff000000) >>> 24;
-    int length = (w2 & 0xffffff);
-
-    if (control) {
-      int version = (w1 & 0x7fff0000) >>> 16;
-      int type = (w1 & 0xffff);
-
-      if (version != 3) {
-        throw new ProtocolException("version != 3: " + version);
-      }
-
-      switch (type) {
-        case SpdyConnection.TYPE_SYN_STREAM:
-          readSynStream(handler, flags, length);
-          return true;
-
-        case SpdyConnection.TYPE_SYN_REPLY:
-          readSynReply(handler, flags, length);
-          return true;
-
-        case SpdyConnection.TYPE_RST_STREAM:
-          readRstStream(handler, flags, length);
-          return true;
-
-        case SpdyConnection.TYPE_SETTINGS:
-          readSettings(handler, flags, length);
-          return true;
-
-        case SpdyConnection.TYPE_NOOP:
-          if (length != 0) throw ioException("TYPE_NOOP length: %d != 0", length);
-          handler.noop();
-          return true;
-
-        case SpdyConnection.TYPE_PING:
-          readPing(handler, flags, length);
-          return true;
-
-        case SpdyConnection.TYPE_GOAWAY:
-          readGoAway(handler, flags, length);
-          return true;
-
-        case SpdyConnection.TYPE_HEADERS:
-          readHeaders(handler, flags, length);
-          return true;
-
-        case SpdyConnection.TYPE_WINDOW_UPDATE:
-          readWindowUpdate(handler, flags, length);
-          return true;
-
-        case SpdyConnection.TYPE_CREDENTIAL:
-          Util.skipByReading(in, length);
-          throw new UnsupportedOperationException("TODO"); // TODO: implement
-
-        default:
-          throw new IOException("Unexpected frame");
-      }
-    } else {
-      int streamId = w1 & 0x7fffffff;
-      handler.data(flags, streamId, in, length);
-      return true;
-    }
-  }
-
-  private void readSynStream(Handler handler, int flags, int length) throws IOException {
-    int w1 = in.readInt();
-    int w2 = in.readInt();
-    int s3 = in.readShort();
-    int streamId = w1 & 0x7fffffff;
-    int associatedStreamId = w2 & 0x7fffffff;
-    int priority = (s3 & 0xe000) >>> 13;
-    int slot = s3 & 0xff;
-    List<String> nameValueBlock = readNameValueBlock(length - 10);
-    handler.synStream(flags, streamId, associatedStreamId, priority, slot, nameValueBlock);
-  }
-
-  private void readSynReply(Handler handler, int flags, int length) throws IOException {
-    int w1 = in.readInt();
-    int streamId = w1 & 0x7fffffff;
-    List<String> nameValueBlock = readNameValueBlock(length - 4);
-    handler.synReply(flags, streamId, nameValueBlock);
-  }
-
-  private void readRstStream(Handler handler, int flags, int length) throws IOException {
-    if (length != 8) throw ioException("TYPE_RST_STREAM length: %d != 8", length);
-    int streamId = in.readInt() & 0x7fffffff;
-    int statusCode = in.readInt();
-    handler.rstStream(flags, streamId, statusCode);
-  }
-
-  private void readHeaders(Handler handler, int flags, int length) throws IOException {
-    int w1 = in.readInt();
-    int streamId = w1 & 0x7fffffff;
-    List<String> nameValueBlock = readNameValueBlock(length - 4);
-    handler.headers(flags, streamId, nameValueBlock);
-  }
-
-  private void readWindowUpdate(Handler handler, int flags, int length) throws IOException {
-    if (length != 8) throw ioException("TYPE_WINDOW_UPDATE length: %d != 8", length);
-    int w1 = in.readInt();
-    int w2 = in.readInt();
-    int streamId = w1 & 0x7fffffff;
-    int deltaWindowSize = w2 & 0x7fffffff;
-    handler.windowUpdate(flags, streamId, deltaWindowSize);
-  }
-
-  private DataInputStream newNameValueBlockStream() {
-    // Limit the inflater input stream to only those bytes in the Name/Value block.
-    final InputStream throttleStream = new InputStream() {
-      @Override public int read() throws IOException {
-        return Util.readSingleByte(this);
-      }
-
-      @Override public int read(byte[] buffer, int offset, int byteCount) throws IOException {
-        byteCount = Math.min(byteCount, compressedLimit);
-        int consumed = in.read(buffer, offset, byteCount);
-        compressedLimit -= consumed;
-        return consumed;
-      }
-
-      @Override public void close() throws IOException {
-        in.close();
-      }
-    };
-
-    // Subclass inflater to install a dictionary when it's needed.
-    Inflater inflater = new Inflater() {
-      @Override public int inflate(byte[] buffer, int offset, int count)
-          throws DataFormatException {
-        int result = super.inflate(buffer, offset, count);
-        if (result == 0 && needsDictionary()) {
-          setDictionary(DICTIONARY);
-          result = super.inflate(buffer, offset, count);
-        }
-        return result;
-      }
-    };
-
-    return new DataInputStream(new InflaterInputStream(throttleStream, inflater));
-  }
-
-  private List<String> readNameValueBlock(int length) throws IOException {
-    this.compressedLimit += length;
-    try {
-      int numberOfPairs = nameValueBlockIn.readInt();
-      if (numberOfPairs < 0) {
-        Logger.getLogger(getClass().getName()).warning("numberOfPairs < 0: " + numberOfPairs);
-        throw ioException("numberOfPairs < 0");
-      }
-      List<String> entries = new ArrayList<String>(numberOfPairs * 2);
-      for (int i = 0; i < numberOfPairs; i++) {
-        String name = readString();
-        String values = readString();
-        if (name.length() == 0) throw ioException("name.length == 0");
-        if (values.length() == 0) throw ioException("values.length == 0");
-        entries.add(name);
-        entries.add(values);
-      }
-
-      if (compressedLimit != 0) {
-        Logger.getLogger(getClass().getName()).warning("compressedLimit > 0: " + compressedLimit);
-      }
-
-      return entries;
-    } catch (DataFormatException e) {
-      throw new IOException(e.getMessage());
-    }
-  }
-
-  private String readString() throws DataFormatException, IOException {
-    int length = nameValueBlockIn.readInt();
-    byte[] bytes = new byte[length];
-    Util.readFully(nameValueBlockIn, bytes);
-    return new String(bytes, 0, length, "UTF-8");
-  }
-
-  private void readPing(Handler handler, int flags, int length) throws IOException {
-    if (length != 4) throw ioException("TYPE_PING length: %d != 4", length);
-    int id = in.readInt();
-    handler.ping(flags, id);
-  }
-
-  private void readGoAway(Handler handler, int flags, int length) throws IOException {
-    if (length != 8) throw ioException("TYPE_GOAWAY length: %d != 8", length);
-    int lastGoodStreamId = in.readInt() & 0x7fffffff;
-    int statusCode = in.readInt();
-    handler.goAway(flags, lastGoodStreamId, statusCode);
-  }
-
-  private void readSettings(Handler handler, int flags, int length) throws IOException {
-    int numberOfEntries = in.readInt();
-    if (length != 4 + 8 * numberOfEntries) {
-      throw ioException("TYPE_SETTINGS length: %d != 4 + 8 * %d", length, numberOfEntries);
-    }
-    Settings settings = new Settings();
-    for (int i = 0; i < numberOfEntries; i++) {
-      int w1 = in.readInt();
-      int value = in.readInt();
-      int idFlags = (w1 & 0xff000000) >>> 24;
-      int id = w1 & 0xffffff;
-      settings.set(id, idFlags, value);
-    }
-    handler.settings(flags, settings);
-  }
-
-  private static IOException ioException(String message, Object... args) throws IOException {
-    throw new IOException(String.format(message, args));
-  }
-
-  @Override public void close() throws IOException {
-    Util.closeAll(in, nameValueBlockIn);
-  }
+/** Reads transport frames for SPDY/3 or HTTP/2.0. */
+public interface SpdyReader extends Closeable {
+  boolean nextFrame(Handler handler) throws IOException;
 
   public interface Handler {
     void data(int flags, int streamId, InputStream in, int length) throws IOException;
-
     void synStream(int flags, int streamId, int associatedStreamId, int priority, int slot,
         List<String> nameValueBlock);
-
     void synReply(int flags, int streamId, List<String> nameValueBlock) throws IOException;
     void headers(int flags, int streamId, List<String> nameValueBlock) throws IOException;
     void rstStream(int flags, int streamId, int statusCode);

okhttp-protocols/src/main/java/com/squareup/okhttp/internal/spdy/SpdyWriter.java

@@ -16,161 +16,25 @@
 
 package com.squareup.okhttp.internal.spdy;
 
-import com.squareup.okhttp.internal.Platform;
-import com.squareup.okhttp.internal.Util;
-import java.io.ByteArrayOutputStream;
 import java.io.Closeable;
-import java.io.DataOutputStream;
 import java.io.IOException;
-import java.io.OutputStream;
 import java.util.List;
-import java.util.zip.Deflater;
 
-/** Write spdy/3 frames. */
-final class SpdyWriter implements Closeable {
-  final DataOutputStream out;
-  private final ByteArrayOutputStream nameValueBlockBuffer;
-  private final DataOutputStream nameValueBlockOut;
-
-  SpdyWriter(OutputStream out) {
-    this.out = new DataOutputStream(out);
-
-    Deflater deflater = new Deflater();
-    deflater.setDictionary(SpdyReader.DICTIONARY);
-    nameValueBlockBuffer = new ByteArrayOutputStream();
-    nameValueBlockOut = new DataOutputStream(
-        Platform.get().newDeflaterOutputStream(nameValueBlockBuffer, deflater, true));
-  }
-
-  public synchronized void synStream(int flags, int streamId, int associatedStreamId, int priority,
-      int slot, List<String> nameValueBlock) throws IOException {
-    writeNameValueBlockToBuffer(nameValueBlock);
-    int length = 10 + nameValueBlockBuffer.size();
-    int type = SpdyConnection.TYPE_SYN_STREAM;
-
-    int unused = 0;
-    out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
-    out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
-    out.writeInt(streamId & 0x7fffffff);
-    out.writeInt(associatedStreamId & 0x7fffffff);
-    out.writeShort((priority & 0x7) << 13 | (unused & 0x1f) << 8 | (slot & 0xff));
-    nameValueBlockBuffer.writeTo(out);
-    out.flush();
-  }
-
-  public synchronized void synReply(int flags, int streamId, List<String> nameValueBlock)
-      throws IOException {
-    writeNameValueBlockToBuffer(nameValueBlock);
-    int type = SpdyConnection.TYPE_SYN_REPLY;
-    int length = nameValueBlockBuffer.size() + 4;
-
-    out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
-    out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
-    out.writeInt(streamId & 0x7fffffff);
-    nameValueBlockBuffer.writeTo(out);
-    out.flush();
-  }
-
-  public synchronized void headers(int flags, int streamId, List<String> nameValueBlock)
-      throws IOException {
-    writeNameValueBlockToBuffer(nameValueBlock);
-    int type = SpdyConnection.TYPE_HEADERS;
-    int length = nameValueBlockBuffer.size() + 4;
-
-    out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
-    out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
-    out.writeInt(streamId & 0x7fffffff);
-    nameValueBlockBuffer.writeTo(out);
-    out.flush();
-  }
-
-  public synchronized void rstStream(int streamId, int statusCode) throws IOException {
-    int flags = 0;
-    int type = SpdyConnection.TYPE_RST_STREAM;
-    int length = 8;
-    out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
-    out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
-    out.writeInt(streamId & 0x7fffffff);
-    out.writeInt(statusCode);
-    out.flush();
-  }
-
-  public synchronized void data(int flags, int streamId, byte[] data) throws IOException {
-    int length = data.length;
-    out.writeInt(streamId & 0x7fffffff);
-    out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
-    out.write(data);
-    out.flush();
-  }
-
-  private void writeNameValueBlockToBuffer(List<String> nameValueBlock) throws IOException {
-    nameValueBlockBuffer.reset();
-    int numberOfPairs = nameValueBlock.size() / 2;
-    nameValueBlockOut.writeInt(numberOfPairs);
-    for (String s : nameValueBlock) {
-      nameValueBlockOut.writeInt(s.length());
-      nameValueBlockOut.write(s.getBytes("UTF-8"));
-    }
-    nameValueBlockOut.flush();
-  }
-
-  public synchronized void settings(int flags, Settings settings) throws IOException {
-    int type = SpdyConnection.TYPE_SETTINGS;
-    int size = settings.size();
-    int length = 4 + size * 8;
-    out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
-    out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
-    out.writeInt(size);
-    for (int i = 0; i <= Settings.COUNT; i++) {
-      if (!settings.isSet(i)) continue;
-      int settingsFlags = settings.flags(i);
-      out.writeInt((settingsFlags & 0xff) << 24 | (i & 0xffffff));
-      out.writeInt(settings.get(i));
-    }
-    out.flush();
-  }
-
-  public synchronized void noop() throws IOException {
-    int type = SpdyConnection.TYPE_NOOP;
-    int length = 0;
-    int flags = 0;
-    out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
-    out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
-    out.flush();
-  }
-
-  public synchronized void ping(int flags, int id) throws IOException {
-    int type = SpdyConnection.TYPE_PING;
-    int length = 4;
-    out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
-    out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
-    out.writeInt(id);
-    out.flush();
-  }
-
-  public synchronized void goAway(int flags, int lastGoodStreamId, int statusCode)
-      throws IOException {
-    int type = SpdyConnection.TYPE_GOAWAY;
-    int length = 8;
-    out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
-    out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
-    out.writeInt(lastGoodStreamId);
-    out.writeInt(statusCode);
-    out.flush();
-  }
-
-  public synchronized void windowUpdate(int streamId, int deltaWindowSize) throws IOException {
-    int type = SpdyConnection.TYPE_WINDOW_UPDATE;
-    int flags = 0;
-    int length = 8;
-    out.writeInt(0x80000000 | (SpdyConnection.VERSION & 0x7fff) << 16 | type & 0xffff);
-    out.writeInt((flags & 0xff) << 24 | length & 0xffffff);
-    out.writeInt(streamId);
-    out.writeInt(deltaWindowSize);
-    out.flush();
-  }
-
-  @Override public void close() throws IOException {
-    Util.closeAll(out, nameValueBlockOut);
-  }
+/** Writes transport frames for SPDY/3 or HTTP/2.0. */
+public interface SpdyWriter extends Closeable {
+  void connectionHeader();
+  /** Writes a complete variant-specific frame. */
+  void writeFrame(byte[] data, int offset, int length) throws IOException;
+  void flush() throws IOException;
+  void synStream(int flags, int streamId, int associatedStreamId, int priority, int slot,
+      List<String> nameValueBlock) throws IOException;
+  void synReply(int flags, int streamId, List<String> nameValueBlock) throws IOException;
+  void headers(int flags, int streamId, List<String> nameValueBlock) throws IOException;
+  void rstStream(int streamId, int statusCode) throws IOException;
+  void data(int flags, int streamId, byte[] data) throws IOException;
+  void settings(int flags, Settings settings) throws IOException;
+  void noop() throws IOException;
+  void ping(int flags, int id) throws IOException;
+  void goAway(int flags, int lastGoodStreamId, int statusCode) throws IOException;
+  void windowUpdate(int streamId, int deltaWindowSize) throws IOException;
 }

okhttp-protocols/src/main/java/com/squareup/okhttp/internal/spdy/Variant.java

@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2013 Square, Inc.
+ *
+ * Licensed 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 com.squareup.okhttp.internal.spdy;
+
+import java.io.InputStream;
+import java.io.OutputStream;
+
+/** A version and dialect of the framed socket protocol. */
+interface Variant {
+  Variant SPDY3 = new Spdy3();
+  Variant HTTP_20_DRAFT_04 = new Http20Draft04();
+
+  SpdyReader newReader(InputStream in);
+  SpdyWriter newWriter(OutputStream out);
+}

okhttp-protocols/src/test/java/com/squareup/okhttp/internal/spdy/MockSpdyPeer.java

@@ -38,7 +38,7 @@ import static java.util.concurrent.Executors.defaultThreadFactory;
 public final class MockSpdyPeer implements Closeable {
   private int frameCount = 0;
   private final ByteArrayOutputStream bytesOut = new ByteArrayOutputStream();
-  private final SpdyWriter spdyWriter = new SpdyWriter(bytesOut);
+  private final SpdyWriter spdyWriter = Variant.SPDY3.newWriter(bytesOut);
   private final List<OutFrame> outFrames = new ArrayList<OutFrame>();
   private final BlockingQueue<InFrame> inFrames = new LinkedBlockingQueue<InFrame>();
   private int port;
@@ -94,7 +94,7 @@ public final class MockSpdyPeer implements Closeable {
     socket = serverSocket.accept();
     OutputStream out = socket.getOutputStream();
     InputStream in = socket.getInputStream();
-    SpdyReader reader = new SpdyReader(in);
+    SpdyReader reader = Variant.SPDY3.newReader(in);
 
     Iterator<OutFrame> outFramesIterator = outFrames.iterator();
     byte[] outBytes = bytesOut.toByteArray();

okhttp/src/main/java/com/squareup/okhttp/Connection.java

@@ -159,6 +159,7 @@ public final class Connection implements Closeable {
         sslSocket.setSoTimeout(0); // SPDY timeouts are set per-stream.
         spdyConnection = new SpdyConnection.Builder(route.address.getUriHost(), true, in, out)
             .build();
+        spdyConnection.sendConnectionHeader();
       } else if (!Arrays.equals(selectedProtocol, HTTP_11)) {
         throw new IOException(
             "Unexpected NPN transport " + new String(selectedProtocol, "ISO-8859-1"));
@@ -256,7 +257,8 @@ public final class Connection implements Closeable {
 
   /** Returns the transport appropriate for this connection. */
   public Object newTransport(HttpEngine httpEngine) throws IOException {
-    return (spdyConnection != null) ? new SpdyTransport(httpEngine, spdyConnection)
+    return (spdyConnection != null)
+        ? new SpdyTransport(httpEngine, spdyConnection)
         : new HttpTransport(httpEngine, out, in);
   }