From 29a595f82cbba7d8fba2a6f3c7ccda53c25e7e67 Mon Sep 17 00:00:00 2001
From: Andrei Arlou <andrei.arlou@gmail.com>
Date: Mon, 23 Aug 2021 12:16:34 +0300
Subject: [PATCH] Use generic type inference and method references in
 FlowDocTest.java (#30478)

---
 .../test/java/jdocs/stream/FlowDocTest.java    | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/akka-docs/src/test/java/jdocs/stream/FlowDocTest.java b/akka-docs/src/test/java/jdocs/stream/FlowDocTest.java
index f6ee45791b..a874616ef2 100644
--- a/akka-docs/src/test/java/jdocs/stream/FlowDocTest.java
+++ b/akka-docs/src/test/java/jdocs/stream/FlowDocTest.java
@@ -52,12 +52,11 @@ public class FlowDocTest extends AbstractJavaTest {
     final Source<Integer, NotUsed> source =
         Source.from(Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10));
     source.map(x -> 0); // has no effect on source, since it's immutable
-    source.runWith(Sink.fold(0, (agg, next) -> agg + next), system); // 55
+    source.runWith(Sink.fold(0, Integer::sum), system); // 55
 
     // returns new Source<Integer>, with `map()` appended
     final Source<Integer, NotUsed> zeroes = source.map(x -> 0);
-    final Sink<Integer, CompletionStage<Integer>> fold =
-        Sink.<Integer, Integer>fold(0, (agg, next) -> agg + next);
+    final Sink<Integer, CompletionStage<Integer>> fold = Sink.fold(0, Integer::sum);
     zeroes.runWith(fold, system); // 0
     // #source-immutable
 
@@ -71,8 +70,7 @@ public class FlowDocTest extends AbstractJavaTest {
     final Source<Integer, NotUsed> source =
         Source.from(Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10));
     // note that the Future is scala.concurrent.Future
-    final Sink<Integer, CompletionStage<Integer>> sink =
-        Sink.<Integer, Integer>fold(0, (aggr, next) -> aggr + next);
+    final Sink<Integer, CompletionStage<Integer>> sink = Sink.fold(0, Integer::sum);
 
     // connect the Source to the Sink, obtaining a RunnableFlow
     final RunnableGraph<CompletionStage<Integer>> runnable = source.toMat(sink, Keep.right());
@@ -90,8 +88,7 @@ public class FlowDocTest extends AbstractJavaTest {
     // #materialization-runWith
     final Source<Integer, NotUsed> source =
         Source.from(Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10));
-    final Sink<Integer, CompletionStage<Integer>> sink =
-        Sink.<Integer, Integer>fold(0, (aggr, next) -> aggr + next);
+    final Sink<Integer, CompletionStage<Integer>> sink = Sink.fold(0, Integer::sum);
 
     // materialize the flow, getting the Sinks materialized value
     final CompletionStage<Integer> sum = source.runWith(sink, system);
@@ -105,8 +102,7 @@ public class FlowDocTest extends AbstractJavaTest {
   public void materializedMapUnique() throws Exception {
     // #stream-reuse
     // connect the Source to the Sink, obtaining a RunnableGraph
-    final Sink<Integer, CompletionStage<Integer>> sink =
-        Sink.<Integer, Integer>fold(0, (aggr, next) -> aggr + next);
+    final Sink<Integer, CompletionStage<Integer>> sink = Sink.fold(0, Integer::sum);
     final RunnableGraph<CompletionStage<Integer>> runnable =
         Source.from(Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)).toMat(sink, Keep.right());
 
@@ -147,7 +143,7 @@ public class FlowDocTest extends AbstractJavaTest {
   public void creatingSourcesSinks() throws Exception {
     // #source-sink
     // Create a source from an Iterable
-    List<Integer> list = new LinkedList<Integer>();
+    List<Integer> list = new LinkedList<>();
     list.add(1);
     list.add(2);
     list.add(3);
@@ -164,7 +160,7 @@ public class FlowDocTest extends AbstractJavaTest {
 
     // Sink that folds over the stream and returns a Future
     // of the final result in the MaterializedMap
-    Sink.fold(0, (Integer aggr, Integer next) -> aggr + next);
+    Sink.fold(0, Integer::sum);
 
     // Sink that returns a Future in the MaterializedMap,
     // containing the first element of the stream