=str #22437 replace require() with if calls to avoid fn allocs

akka-bench-jmh/src/main/scala/akka/stream/MaterializationBenchmark.scala

@@ -84,7 +84,7 @@ class MaterializationBenchmark {
   var graphWithNestedImports: RunnableGraph[NotUsed] = _
   var graphWithImportedFlow: RunnableGraph[NotUsed] = _
 
-  @Param(Array("1", "10"))
+  @Param(Array("1", "10", "100", "1000"))
   var complexity = 0
 
   @Setup

akka-stream/src/main/scala/akka/stream/impl/ActorMaterializerImpl.scala

@@ -87,8 +87,6 @@ abstract class ExtendedActorMaterializer extends ActorMaterializer {
  * The default phases are left in-tact since we still respect `.async` and other tags that were marked within a sub-fused graph.
  */
 private[akka] class SubFusingActorMaterializerImpl(val delegate: ExtendedActorMaterializer, registerShell: GraphInterpreterShell ⇒ ActorRef) extends Materializer {
-  require(registerShell ne null, "When using SubFusing the subflowFuser MUST NOT be null.") // FIXME remove check?
-
   val subFusingPhase = new Phase[Any] {
     override def apply(settings: ActorMaterializerSettings, materializer: PhasedFusingActorMaterializer, islandName: String): PhaseIsland[Any] = {
       new GraphStageIsland(settings, materializer, islandName, OptionVal(registerShell)).asInstanceOf[PhaseIsland[Any]]

akka-stream/src/main/scala/akka/stream/impl/ActorProcessor.scala

@@ -47,8 +47,9 @@ private[akka] class ActorProcessor[I, O](impl: ActorRef) extends ActorPublisher[
  * INTERNAL API
  */
 private[akka] abstract class BatchingInputBuffer(val size: Int, val pump: Pump) extends DefaultInputTransferStates {
-  require(size > 0, "buffer size cannot be zero")
-  require((size & (size - 1)) == 0, "buffer size must be a power of two")
+  if (size < 1) throw new IllegalArgumentException(s"buffer size MSUT be positive (was: $size")
+  if ((size & (size - 1)) != 0) throw new IllegalArgumentException("buffer size must be a power of two")
+
   // TODO: buffer and batch sizing heuristics
   private var upstream: Subscription = _
   private val inputBuffer = Array.ofDim[AnyRef](size)
@@ -114,7 +115,7 @@ private[akka] abstract class BatchingInputBuffer(val size: Int, val pump: Pump)
   }
 
   protected def onSubscribe(subscription: Subscription): Unit = {
-    require(subscription != null)
+    ReactiveStreamsCompliance.requireNonNullSubscription(subscription)
     if (upstreamCompleted) subscription.cancel()
     else {
       upstream = subscription

akka-stream/src/main/scala/akka/stream/impl/TraversalBuilder.scala

@@ -480,8 +480,8 @@ object LinearTraversalBuilder {
    * than its generic counterpart. It can be freely mixed with the generic builder in both ways.
    */
   def fromModule(module: AtomicModule[Shape, Any], attributes: Attributes): LinearTraversalBuilder = {
-    require(module.shape.inlets.size <= 1, "Modules with more than one input port cannot be linear.")
-    require(module.shape.outlets.size <= 1, "Modules with more than one input port cannot be linear.")
+    if (module.shape.inlets.size > 1) throw new IllegalStateException("Modules with more than one input port cannot be linear.")
+    if (module.shape.outlets.size > 1) throw new IllegalStateException("Modules with more than one input port cannot be linear.")
     TraversalBuilder.initShape(module.shape)
 
     val inPortOpt = OptionVal(module.shape.inlets.headOption.orNull)
@@ -708,8 +708,8 @@ final case class LinearTraversalBuilder(
         traversalSoFar = toAppend.traversalSoFar.concat(LinearTraversalBuilder.addMatCompose(traversal, matCompose)))
     } else {
       if (outPort.isDefined) {
-        require(toAppend.inPort.isDefined, "Appended linear module must have an unwired input port " +
-          "because there is a dangling output.")
+        if (toAppend.inPort.isEmpty)
+          throw new IllegalArgumentException("Appended linear module must have an unwired input port because there is a dangling output.")
 
         /*
          * To understand how append work, first the general structure of the LinearTraversalBuilder must be

akka-stream/src/main/scala/akka/stream/impl/fusing/ActorGraphInterpreter.scala

@@ -89,8 +89,8 @@ object ActorGraphInterpreter {
       override def logic: GraphStageLogic = BatchingActorInputBoundary.this
     }
 
-    require(size > 0, "buffer size cannot be zero")
-    require((size & (size - 1)) == 0, "buffer size must be a power of two")
+    if (size <= 0) throw new IllegalArgumentException("buffer size cannot be zero")
+    if ((size & (size - 1)) != 0) throw new IllegalArgumentException("buffer size must be a power of two")
 
     private var actor: ActorRef = ActorRef.noSender
     private var upstream: Subscription = _
@@ -136,7 +136,7 @@ object ActorGraphInterpreter {
 
     private def dequeue(): Any = {
       val elem = inputBuffer(nextInputElementCursor)
-      require(elem ne null, "Internal queue must never contain a null")
+      if (elem eq null) throw new IllegalArgumentException("Internal queue must never contain a null")
       inputBuffer(nextInputElementCursor) = null
 
       batchRemaining -= 1
@@ -196,7 +196,7 @@ object ActorGraphInterpreter {
       }
 
     def onSubscribe(subscription: Subscription): Unit = {
-      require(subscription != null, "Subscription cannot be null")
+      ReactiveStreamsCompliance.requireNonNullSubscription(subscription)
       if (upstreamCompleted) {
         tryCancel(subscription)
       } else if (downstreamCanceled) {