From 54d91c180ae9d4a5ed264e5cbcb24bdc17257df0 Mon Sep 17 00:00:00 2001
From: Johannes Rudolph <johannes.rudolph@gmail.com>
Date: Tue, 9 Apr 2013 12:25:43 +0200
Subject: [PATCH] Tcp: abstract writing into WriteCommand to make place for
 other kinds of writing

---
 akka-actor/src/main/scala/akka/io/Tcp.scala       | 13 ++++++++-----
 .../src/main/scala/akka/io/TcpConnection.scala    | 15 ++++++++-------
 2 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/akka-actor/src/main/scala/akka/io/Tcp.scala b/akka-actor/src/main/scala/akka/io/Tcp.scala
index b1a9bb62f2..490619f67f 100644
--- a/akka-actor/src/main/scala/akka/io/Tcp.scala
+++ b/akka-actor/src/main/scala/akka/io/Tcp.scala
@@ -92,15 +92,18 @@ object Tcp extends ExtensionKey[TcpExt] {
   case class NoAck(token: Any)
   object NoAck extends NoAck(null)
 
+  sealed trait WriteCommand extends Command {
+    require(ack != null, "ack must be non-null. Use NoAck if you don't want acks.")
+
+    def ack: Any
+    def wantsAck: Boolean = !ack.isInstanceOf[NoAck]
+  }
+
   /**
    * Write data to the TCP connection. If no ack is needed use the special
    * `NoAck` object.
    */
-  case class Write(data: ByteString, ack: Any) extends Command {
-    require(ack != null, "ack must be non-null. Use NoAck if you don't want acks.")
-
-    def wantsAck: Boolean = !ack.isInstanceOf[NoAck]
-  }
+  case class Write(data: ByteString, ack: Any) extends WriteCommand
   object Write {
     val Empty: Write = Write(ByteString.empty, NoAck)
     def apply(data: ByteString): Write =
diff --git a/akka-actor/src/main/scala/akka/io/TcpConnection.scala b/akka-actor/src/main/scala/akka/io/TcpConnection.scala
index 98c2c0cf1f..d64cd71fec 100644
--- a/akka-actor/src/main/scala/akka/io/TcpConnection.scala
+++ b/akka-actor/src/main/scala/akka/io/TcpConnection.scala
@@ -103,7 +103,7 @@ private[io] abstract class TcpConnection(val channel: SocketChannel,
   def handleWriteMessages(handler: ActorRef): Receive = {
     case ChannelWritable ⇒ if (writePending) doWrite(handler)
 
-    case write: Write if writePending ⇒
+    case write: WriteCommand if writePending ⇒
       if (TraceLogging) log.debug("Dropping write because queue is full")
       sender ! write.failureMessage
 
@@ -111,7 +111,7 @@ private[io] abstract class TcpConnection(val channel: SocketChannel,
       if (write.wantsAck)
         sender ! write.ack
 
-    case write: Write ⇒
+    case write: WriteCommand ⇒
       pendingWrite = createWrite(write)
       doWrite(handler)
   }
@@ -297,12 +297,13 @@ private[io] abstract class TcpConnection(val channel: SocketChannel,
         copy(remainingData = remainingData.drop(copied))
       } else this
   }
-  def createWrite(write: Write): PendingWrite = {
-    val buffer = bufferPool.acquire()
-    val copied = write.data.copyToBuffer(buffer)
-    buffer.flip()
+  def createWrite(write: WriteCommand): PendingWrite = write match {
+    case write: Write ⇒
+      val buffer = bufferPool.acquire()
+      val copied = write.data.copyToBuffer(buffer)
+      buffer.flip()
 
-    PendingBufferWrite(sender, write.ack, write.data.drop(copied), buffer)
+      PendingBufferWrite(sender, write.ack, write.data.drop(copied), buffer)
   }
 }