Materializer settings as attributes (#27499)

* Replace MaterializerSettings with Attributes #25559 
 * Field access to settings deprecated to make stages use attributes instead
 * Internal stages updated to use attributes
 * Docs on ActorMaterializerSettings updated to recommend away from using it
 * Verify all stages stopped after each testcase in FlowGroupBySpec
 * Subscription timeout attributes merged into one

akka-docs/src/test/java/jdocs/stream/FlowErrorDocTest.java

@@ -13,6 +13,7 @@ import java.util.concurrent.TimeUnit;
 
 import akka.NotUsed;
 import akka.japi.pf.PFBuilder;
+import akka.stream.javadsl.*;
 import jdocs.AbstractJavaTest;
 import akka.testkit.javadsl.TestKit;
 import org.junit.AfterClass;
@@ -22,10 +23,7 @@ import org.junit.Test;
 import akka.actor.ActorSystem;
 import akka.stream.Materializer;
 import akka.stream.Supervision;
-import akka.stream.javadsl.Flow;
 import akka.stream.ActorAttributes;
-import akka.stream.javadsl.Sink;
-import akka.stream.javadsl.Source;
 import akka.japi.function.Function;
 
 public class FlowErrorDocTest extends AbstractJavaTest {
@@ -71,7 +69,13 @@ public class FlowErrorDocTest extends AbstractJavaTest {
             .map(elem -> 100 / elem)
             .withAttributes(ActorAttributes.withSupervisionStrategy(decider));
     final Sink<Integer, CompletionStage<Integer>> fold = Sink.fold(0, (acc, elem) -> acc + elem);
-    final CompletionStage<Integer> result = source.runWith(fold, system);
+
+    final RunnableGraph<CompletionStage<Integer>> runnableGraph = source.toMat(fold, Keep.right());
+
+    final RunnableGraph<CompletionStage<Integer>> withCustomSupervision =
+        runnableGraph.withAttributes(ActorAttributes.withSupervisionStrategy(decider));
+
+    final CompletionStage<Integer> result = withCustomSupervision.run(system);
     // the element causing division by zero will be dropped
     // result here will be a CompletionStage completed with 228
     // #resume

akka-docs/src/test/java/jdocs/stream/IntegrationDocTest.java

@@ -663,10 +663,6 @@ public class IntegrationDocTest extends AbstractJavaTest {
         final Executor blockingEc = system.dispatchers().lookup("blocking-dispatcher");
         final SometimesSlowService service = new SometimesSlowService(blockingEc);
 
-        final ActorMaterializer mat =
-            ActorMaterializer.create(
-                ActorMaterializerSettings.create(system).withInputBuffer(4, 4), system);
-
         Source.from(Arrays.asList("a", "B", "C", "D", "e", "F", "g", "H", "i", "J"))
             .map(
                 elem -> {
@@ -674,7 +670,9 @@ public class IntegrationDocTest extends AbstractJavaTest {
                   return elem;
                 })
             .mapAsync(4, service::convert)
-            .runForeach(elem -> System.out.println("after: " + elem), system);
+            .to(Sink.foreach(elem -> System.out.println("after: " + elem)))
+            .withAttributes(Attributes.inputBuffer(4, 4))
+            .run(system);
         // #sometimes-slow-mapAsync
 
         probe.expectMsg("after: A");

akka-docs/src/test/java/jdocs/stream/StreamBuffersRateDocTest.java

@@ -66,12 +66,6 @@ public class StreamBuffersRateDocTest extends AbstractJavaTest {
   @Test
   @SuppressWarnings("unused")
   public void demonstrateBufferSizes() {
-    // #materializer-buffer
-    final Materializer materializer =
-        ActorMaterializer.create(
-            ActorMaterializerSettings.create(system).withInputBuffer(64, 64), system);
-    // #materializer-buffer
-
     // #section-buffer
     final Flow<Integer, Integer, NotUsed> flow1 =
         Flow.of(Integer.class)
@@ -81,7 +75,13 @@ public class StreamBuffersRateDocTest extends AbstractJavaTest {
     final Flow<Integer, Integer, NotUsed> flow2 =
         flow1
             .via(Flow.of(Integer.class).map(elem -> elem / 2))
-            .async(); // the buffer size of this map is the default
+            .async(); // the buffer size of this map is the value from the surrounding graph it is
+    // used in
+    final RunnableGraph<NotUsed> runnableGraph =
+        Source.range(1, 10).via(flow1).to(Sink.foreach(elem -> System.out.println(elem)));
+
+    final RunnableGraph<NotUsed> withOverridenDefaults =
+        runnableGraph.withAttributes(Attributes.inputBuffer(64, 64));
     // #section-buffer
   }