!str #17039 change default materialization placeholder type from Unit to Any

akka-stream-tests/src/test/java/akka/stream/javadsl/FlowGraphTest.java

@@ -66,10 +66,10 @@ public class FlowGraphTest extends StreamTest {
         .of(String.class)
         .section(
             OperationAttributes.name("f1"),
-            new Function<Flow<String, String, BoxedUnit>, Flow<String, String, BoxedUnit>>() {
+            new Function<Flow<String, String, Object>, Flow<String, String, Object>>() {
               @Override
-              public Flow<String, String, BoxedUnit> apply(
+              public Flow<String, String, Object> apply(
-                  Flow<String, String, BoxedUnit> flow) {
+                  Flow<String, String, Object> flow) {
                 return flow.transform(FlowGraphTest.this.<String> op());
               }
             });
@@ -77,10 +77,10 @@ public class FlowGraphTest extends StreamTest {
         .of(String.class)
         .section(
             OperationAttributes.name("f2"),
-            new Function<Flow<String, String, BoxedUnit>, Flow<String, String, BoxedUnit>>() {
+            new Function<Flow<String, String, Object>, Flow<String, String, Object>>() {
               @Override
-              public Flow<String, String, BoxedUnit> apply(
+              public Flow<String, String, Object> apply(
-                  Flow<String, String, BoxedUnit> flow) {
+                  Flow<String, String, Object> flow) {
                 return flow.transform(FlowGraphTest.this.<String> op());
               }
             });
@@ -88,10 +88,10 @@ public class FlowGraphTest extends StreamTest {
         .of(String.class)
         .section(
             OperationAttributes.name("f3"),
-            new Function<Flow<String, String, BoxedUnit>, Flow<String, String, BoxedUnit>>() {
+            new Function<Flow<String, String, Object>, Flow<String, String, Object>>() {
               @Override
-              public Flow<String, String, BoxedUnit> apply(
+              public Flow<String, String, Object> apply(
-                  Flow<String, String, BoxedUnit> flow) {
+                  Flow<String, String, Object> flow) {
                 return flow.transform(FlowGraphTest.this.<String> op());
               }
             });

akka-stream-tests/src/test/java/akka/stream/javadsl/FlowTest.java

@@ -19,6 +19,7 @@ import akka.testkit.JavaTestKit;
 
 import org.reactivestreams.Publisher;
 
+import scala.runtime.Boxed;
 import scala.runtime.BoxedUnit;
 
 import org.junit.ClassRule;
@@ -245,10 +246,10 @@ public class FlowTest extends StreamTest {
         .of(String.class)
         .section(
             OperationAttributes.name("f1"),
-            new Function<Flow<String, String, BoxedUnit>, Flow<String, String, BoxedUnit>>() {
+            new Function<Flow<String, String, Object>, Flow<String, String, Object>>() {
               @Override
-              public Flow<String, String, BoxedUnit> apply(
+              public Flow<String, String, Object> apply(
-                  Flow<String, String, BoxedUnit> flow) {
+                  Flow<String, String, Object> flow) {
                 return flow.transform(FlowTest.this.<String> op());
               }
             });
@@ -256,10 +257,10 @@ public class FlowTest extends StreamTest {
         .of(String.class)
         .section(
             OperationAttributes.name("f2"),
-            new Function<Flow<String, String, BoxedUnit>, Flow<String, String, BoxedUnit>>() {
+            new Function<Flow<String, String, Object>, Flow<String, String, Object>>() {
               @Override
-              public Flow<String, String, BoxedUnit> apply(
+              public Flow<String, String, Object> apply(
-                  Flow<String, String, BoxedUnit> flow) {
+                  Flow<String, String, Object> flow) {
                 return flow.transform(FlowTest.this.<String> op());
               }
             });
@@ -267,10 +268,10 @@ public class FlowTest extends StreamTest {
         .of(String.class)
         .section(
             OperationAttributes.name("f3"),
-            new Function<Flow<String, String, BoxedUnit>, Flow<String, String, BoxedUnit>>() {
+            new Function<Flow<String, String, Object>, Flow<String, String, Object>>() {
               @Override
-              public Flow<String, String, BoxedUnit> apply(
+              public Flow<String, String, Object> apply(
-                  Flow<String, String, BoxedUnit> flow) {
+                  Flow<String, String, Object> flow) {
                 return flow.transform(FlowTest.this.<String> op());
               }
             });
@@ -375,7 +376,7 @@ public class FlowTest extends StreamTest {
     mainInputs.add(Source.from(input2));
 
     final Flow<Source<Integer, BoxedUnit>, List<Integer>, BoxedUnit> flow = Flow.<Source<Integer, BoxedUnit>>create().
-      flatten(akka.stream.javadsl.FlattenStrategy.<Integer> concat()).grouped(6);
+      flatten(akka.stream.javadsl.FlattenStrategy.<Integer, BoxedUnit> concat()).grouped(6);
     Future<List<Integer>> future = Source.from(mainInputs).via(flow)
         .runWith(Sink.<List<Integer>>head(), materializer);
 

akka-stream-tests/src/test/java/akka/stream/javadsl/SourceTest.java

@@ -342,7 +342,7 @@ public class SourceTest extends StreamTest {
     mainInputs.add(Source.from(input2));
 
     Future<List<Integer>> future = Source.from(mainInputs)
-      .flatten(akka.stream.javadsl.FlattenStrategy.<Integer>concat()).grouped(6)
+      .flatten(akka.stream.javadsl.FlattenStrategy.<Integer, BoxedUnit>concat()).grouped(6)
       .runWith(Sink.<List<Integer>>head(), materializer);
 
     List<Integer> result = Await.result(future, probe.dilated(FiniteDuration.create(3, TimeUnit.SECONDS)));

akka-stream/src/main/scala/akka/stream/extra/Timed.scala

@@ -3,14 +3,12 @@
  */
 package akka.stream.extra
 
-import scala.collection.immutable
 import java.util.concurrent.atomic.AtomicLong
 import scala.concurrent.duration._
 import scala.language.implicitConversions
 import scala.language.existentials
 import akka.stream.scaladsl.OperationAttributes._
-import akka.stream.scaladsl.Source
+import akka.stream.scaladsl.{ Keep, Source, Flow }
-import akka.stream.scaladsl.Flow
 import akka.stream.stage._
 
 /**
@@ -28,11 +26,11 @@ private[akka] trait TimedOps {
   def timed[I, O, Mat, Mat2](source: Source[I, Mat], measuredOps: Source[I, Mat] ⇒ Source[O, Mat2], onComplete: FiniteDuration ⇒ Unit): Source[O, Mat2] = {
     val ctx = new TimedFlowContext
 
-    val startTimed = (f: Flow[I, I, Unit]) ⇒ f.transform(() ⇒ new StartTimedFlow(ctx))
+    val startTimed = (f: Flow[I, I, Any]) ⇒ f.transform(() ⇒ new StartTimedFlow(ctx))
-    val stopTimed = (f: Flow[O, O, Unit]) ⇒ f.transform(() ⇒ new StopTimed(ctx, onComplete))
+    val stopTimed = (f: Flow[O, O, Any]) ⇒ f.transform(() ⇒ new StopTimed(ctx, onComplete))
 
-    val begin = source.section(name("startTimed"), (originalMat: Mat, _: Unit) ⇒ originalMat)(startTimed)
+    val begin = source.section(name("startTimed"))(startTimed)
-    measuredOps(begin).section(name("stopTimed"), (originalMat: Mat2, _: Unit) ⇒ originalMat)(stopTimed)
+    measuredOps(begin).section(name("stopTimed"))(stopTimed)
   }
 
   /**
@@ -45,11 +43,11 @@ private[akka] trait TimedOps {
     // they do share a super-type (FlowOps), but all operations of FlowOps return path dependant type
     val ctx = new TimedFlowContext
 
-    val startTimed = (f: Flow[O, O, Unit]) ⇒ f.transform(() ⇒ new StartTimedFlow(ctx))
+    val startTimed = (f: Flow[O, O, Any]) ⇒ f.transform(() ⇒ new StartTimedFlow(ctx))
-    val stopTimed = (f: Flow[Out, Out, Unit]) ⇒ f.transform(() ⇒ new StopTimed(ctx, onComplete))
+    val stopTimed = (f: Flow[Out, Out, Any]) ⇒ f.transform(() ⇒ new StopTimed(ctx, onComplete))
 
-    val begin: Flow[I, O, Mat] = flow.section(name("startTimed"), (originalMat: Mat, _: Unit) ⇒ originalMat)(startTimed)
+    val begin: Flow[I, O, Mat] = flow.section(name("startTimed"))(startTimed)
-    measuredOps(begin).section(name("stopTimed"), (originalMat: Mat2, _: Unit) ⇒ originalMat)(stopTimed)
+    measuredOps(begin).section(name("stopTimed"))(stopTimed)
   }
 
 }
@@ -67,7 +65,7 @@ private[akka] trait TimedIntervalBetweenOps {
    * Measures rolling interval between immediately subsequent `matching(o: O)` elements.
    */
   def timedIntervalBetween[O, Mat](source: Source[O, Mat], matching: O ⇒ Boolean, onInterval: FiniteDuration ⇒ Unit): Source[O, Mat] = {
-    source.section(name("timedInterval"), (originalMat: Mat, _: Unit) ⇒ originalMat) {
+    source.section(name("timedInterval")) {
       _.transform(() ⇒ new TimedIntervalTransformer[O](matching, onInterval))
     }
   }
@@ -78,7 +76,7 @@ private[akka] trait TimedIntervalBetweenOps {
   def timedIntervalBetween[I, O, Mat](flow: Flow[I, O, Mat], matching: O ⇒ Boolean, onInterval: FiniteDuration ⇒ Unit): Flow[I, O, Mat] = {
     // todo is there any other way to provide this for Flow / Duct, without duplicating impl?
     // they do share a super-type (FlowOps), but all operations of FlowOps return path dependant type
-    flow.section(name("timedInterval"), (originalMat: Mat, _: Unit) ⇒ originalMat) {
+    flow.section(name("timedInterval")) {
       _.transform(() ⇒ new TimedIntervalTransformer[O](matching, onInterval))
     }
   }

akka-stream/src/main/scala/akka/stream/javadsl/FlattenStrategy.scala

@@ -17,11 +17,11 @@ object FlattenStrategy {
    * emitting its elements directly to the output until it completes and then taking the next stream. This has the
    * consequence that if one of the input stream is infinite, no other streams after that will be consumed from.
    */
-  def concat[T]: FlattenStrategy[Source[T, Unit], T] = Concat[T]()
+  def concat[T, U]: FlattenStrategy[Source[T, U], T] = Concat[T, U]()
 
   /**
    * INTERNAL API
    */
-  private[akka] final case class Concat[T]() extends FlattenStrategy[Source[T, _], T]
+  private[akka] final case class Concat[T, U]() extends FlattenStrategy[Source[T, U], T]
 
 }

akka-stream/src/main/scala/akka/stream/javadsl/Flow.scala

@@ -411,10 +411,10 @@ class Flow[-In, +Out, +Mat](delegate: scaladsl.Flow[In, Out, Mat]) extends Graph
   /**
    * Applies given [[OperationAttributes]] to a given section.
    */
-  def section[O, M](attributes: OperationAttributes, section: japi.Function[javadsl.Flow[Out, Out, Unit], javadsl.Flow[Out, O, M]] @uncheckedVariance): javadsl.Flow[In, O, M] =
+  def section[O](attributes: OperationAttributes, section: japi.Function[javadsl.Flow[Out, Out, Any], javadsl.Flow[Out, O, Any]] @uncheckedVariance): javadsl.Flow[In, O, Mat] =
     new Flow(delegate.section(attributes.asScala) {
-      val scalaToJava = (flow: scaladsl.Flow[Out, Out, Unit]) ⇒ new javadsl.Flow(flow)
+      val scalaToJava = (flow: scaladsl.Flow[Out, Out, Any]) ⇒ new javadsl.Flow(flow)
-      val javaToScala = (flow: javadsl.Flow[Out, O, M]) ⇒ flow.asScala
+      val javaToScala = (flow: javadsl.Flow[Out, O, Any]) ⇒ flow.asScala
       scalaToJava andThen section.apply andThen javaToScala
     })
 

akka-stream/src/main/scala/akka/stream/javadsl/Source.scala

@@ -501,10 +501,10 @@ class Source[+Out, +Mat](delegate: scaladsl.Source[Out, Mat]) extends Graph[Sour
   /**
    * Applies given [[OperationAttributes]] to a given section.
    */
-  def section[O, M](attributes: OperationAttributes, section: japi.Function[javadsl.Flow[Out, Out, Unit], javadsl.Flow[Out, O, M]] @uncheckedVariance): javadsl.Source[O, M] =
+  def section[O](attributes: OperationAttributes, section: japi.Function[javadsl.Flow[Out, Out, Any], javadsl.Flow[Out, O, Any]] @uncheckedVariance): javadsl.Source[O, Mat] =
     new Source(delegate.section(attributes.asScala) {
-      val scalaToJava = (source: scaladsl.Flow[Out, Out, Unit]) ⇒ new javadsl.Flow(source)
+      val scalaToJava = (source: scaladsl.Flow[Out, Out, Any]) ⇒ new javadsl.Flow(source)
-      val javaToScala = (source: javadsl.Flow[Out, O, M]) ⇒ source.asScala
+      val javaToScala = (source: javadsl.Flow[Out, O, Any]) ⇒ source.asScala
       scalaToJava andThen section.apply andThen javaToScala
     })
 

akka-stream/src/main/scala/akka/stream/scaladsl/FlattenStrategy.scala

@@ -3,12 +3,10 @@
  */
 package akka.stream.scaladsl
 
-import akka.stream.javadsl
-
 /**
  * Strategy that defines how a stream of streams should be flattened into a stream of simple elements.
  */
-abstract class FlattenStrategy[-S, T]
+abstract class FlattenStrategy[-S, +T]
 
 object FlattenStrategy {
 
@@ -17,7 +15,7 @@ object FlattenStrategy {
    * emitting its elements directly to the output until it completes and then taking the next stream. This has the
    * consequence that if one of the input stream is infinite, no other streams after that will be consumed from.
    */
-  def concat[T]: FlattenStrategy[Source[T, _], T] = Concat[T]()
+  def concat[T]: FlattenStrategy[Source[T, Any], T] = Concat[T]()
 
-  private[akka] final case class Concat[T]() extends FlattenStrategy[Source[T, _], T]
+  private[akka] final case class Concat[T]() extends FlattenStrategy[Source[T, Any], T]
 }

akka-stream/src/main/scala/akka/stream/scaladsl/Flow.scala

@@ -269,7 +269,8 @@ final class Flow[-In, +Out, +Mat](private[stream] override val module: Module)
   }
 
   // FIXME remove (in favor of .via)
-  def section[O, O2 >: Out, Mat2, Mat3](attributes: OperationAttributes, combine: (Mat, Mat2) ⇒ Mat3)(section: Flow[O2, O2, Unit] ⇒ Flow[O2, O, Mat2]): Flow[In, O, Mat3] = {
+  def section[O, O2 >: Out, Mat2, Mat3](attributes: OperationAttributes, combine: (Mat, Mat2) ⇒ Mat3)(
+    section: Flow[O2, O2, Unit] ⇒ Flow[O2, O, Mat2]): Flow[In, O, Mat3] = {
     val subFlow = section(Flow[O2]).module.carbonCopy.withAttributes(attributes).wrap()
     if (this.isIdentity) new Flow(subFlow).asInstanceOf[Flow[In, O, Mat3]]
     else new Flow(
@@ -282,8 +283,8 @@ final class Flow[-In, +Out, +Mat](private[stream] override val module: Module)
    * Applies given [[OperationAttributes]] to a given section.
    */
   // FIXME remove (in favor of .via)
-  def section[O, O2 >: Out, Mat2](attributes: OperationAttributes)(section: Flow[O2, O2, Unit] ⇒ Flow[O2, O, Mat2]): Flow[In, O, Mat2] = {
+  def section[O, O2 >: Out](attributes: OperationAttributes)(section: Flow[O2, O2, Unit] ⇒ Flow[O2, O, Any]): Flow[In, O, Mat] = {
-    this.section[O, O2, Mat2, Mat2](attributes, Keep.right)(section)
+    this.section[O, O2, Any, Mat](attributes, Keep.left)(section)
   }
 
   /** Converts this Scala DSL element to it's Java DSL counterpart. */
@@ -632,7 +633,7 @@ trait FlowOps[+Out, +Mat] {
    * This operation can be used on a stream of element type [[akka.stream.scaladsl.Source]].
    */
   def flatten[U](strategy: FlattenStrategy[Out, U]): Repr[U, Mat] = strategy match {
-    case _: FlattenStrategy.Concat[Out] | _: javadsl.FlattenStrategy.Concat[Out] ⇒ andThen(ConcatAll())
+    case _: FlattenStrategy.Concat[Out] | _: javadsl.FlattenStrategy.Concat[Out, _] ⇒ andThen(ConcatAll())
     case _ ⇒
       throw new IllegalArgumentException(s"Unsupported flattening strategy [${strategy.getClass.getName}]")
   }

akka-stream/src/main/scala/akka/stream/scaladsl/Graph.scala

@@ -327,7 +327,7 @@ object FlowGraph extends GraphApply {
         b.addEdge(importAndGetPort(b), to)
       }
 
-      def ~>[Out](via: Flow[T, Out, _])(implicit b: Builder[_]): PortOps[Out, Unit] = {
+      def ~>[Out](via: Flow[T, Out, Any])(implicit b: Builder[_]): PortOps[Out, Unit] = {
         val s = b.add(via)
         b.addEdge(importAndGetPort(b), s.inlet)
         s.outlet

akka-stream/src/main/scala/akka/stream/scaladsl/Source.scala

@@ -147,9 +147,8 @@ final class Source[+Out, +Mat](private[stream] override val module: Module)
         .replaceShape(SourceShape(subFlow.shape.outlets.head)))
   }
 
-  def section[O, O2 >: Out, Mat2](attributes: OperationAttributes)(section: Flow[O2, O2, Unit] ⇒ Flow[O2, O, Mat2]): Source[O, Mat2] = {
+  def section[O, O2 >: Out](attributes: OperationAttributes)(section: Flow[O2, O2, Unit] ⇒ Flow[O2, O, Any]): Source[O, Mat] =
-    this.section[O, O2, Mat2, Mat2](attributes, (parentm: Mat, subm: Mat2) ⇒ subm)(section)
+    this.section[O, O2, Any, Mat](attributes, Keep.left)(section)
-  }
 
   override def withAttributes(attr: OperationAttributes): Repr[Out, Mat] =
     new Source(module.withAttributes(attr).wrap())