From 0a4ea4173f77775ba7251e07ea74113f91094db0 Mon Sep 17 00:00:00 2001
From: Christoph Strobl <cstrobl@vmware.com>
Date: Wed, 22 Mar 2023 08:35:56 +0100
Subject: [PATCH] Add test for result streaming with data-jpa

See: spring-projects/spring-data-jpa#2848
---
 .../com/example/data/jpa/DataJpaApplicationAotTests.java  | 8 ++++++++
 .../main/java/com/example/data/jpa/AuthorRepository.java  | 3 +++
 data/data-jpa/src/main/java/com/example/data/jpa/CLR.java | 8 ++++++++
 3 files changed, 19 insertions(+)

diff --git a/data/data-jpa/src/appTest/java/com/example/data/jpa/DataJpaApplicationAotTests.java b/data/data-jpa/src/appTest/java/com/example/data/jpa/DataJpaApplicationAotTests.java
index 239a2dd3..19f01e6a 100644
--- a/data/data-jpa/src/appTest/java/com/example/data/jpa/DataJpaApplicationAotTests.java
+++ b/data/data-jpa/src/appTest/java/com/example/data/jpa/DataJpaApplicationAotTests.java
@@ -56,6 +56,14 @@ void queryAnnotatedMethod(AssertableOutput output) {
 		});
 	}
 
+	@Test
+	void streamingResult(AssertableOutput output) {
+		Awaitility.await().atMost(Duration.ofSeconds(10)).untilAsserted(() -> {
+			assertThat(output).hasSingleLineContaining("streamAuthors(): author = Author{name='Martin Kleppmann'}")
+				.hasNoLinesContaining("streamAuthors(): author = Author{name='Josh Long'}");
+		});
+	}
+
 	@Test
 	void deleteAll(AssertableOutput output) {
 		Awaitility.await().atMost(Duration.ofSeconds(10)).untilAsserted(() -> {
diff --git a/data/data-jpa/src/main/java/com/example/data/jpa/AuthorRepository.java b/data/data-jpa/src/main/java/com/example/data/jpa/AuthorRepository.java
index 235cab13..794f72b6 100644
--- a/data/data-jpa/src/main/java/com/example/data/jpa/AuthorRepository.java
+++ b/data/data-jpa/src/main/java/com/example/data/jpa/AuthorRepository.java
@@ -1,6 +1,7 @@
 package com.example.data.jpa;
 
 import java.util.Optional;
+import java.util.stream.Stream;
 
 import com.example.data.jpa.model.Author;
 
@@ -14,4 +15,6 @@ public interface AuthorRepository extends ListCrudRepository<Author, Long> {
 	@Query("SELECT a FROM Author a WHERE a.name = :name")
 	Optional<Author> queryFindByName(String name);
 
+	Stream<Author> findByNameContaining(String name);
+
 }
diff --git a/data/data-jpa/src/main/java/com/example/data/jpa/CLR.java b/data/data-jpa/src/main/java/com/example/data/jpa/CLR.java
index 8b8ac80a..bf44ff6a 100644
--- a/data/data-jpa/src/main/java/com/example/data/jpa/CLR.java
+++ b/data/data-jpa/src/main/java/com/example/data/jpa/CLR.java
@@ -4,6 +4,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Set;
+import java.util.stream.Stream;
 
 import com.example.data.jpa.model.Author;
 import com.example.data.jpa.model.Book;
@@ -32,6 +33,7 @@ public void run(String... args) {
 		findById(authors);
 		findByPartialName();
 		queryFindByName();
+		streamAuthors();
 		deleteAll();
 		entityGraph();
 	}
@@ -87,6 +89,12 @@ private void listAllAuthors() {
 		}
 	}
 
+	private void streamAuthors() {
+
+		Stream<Author> authors = this.authorRepository.findByNameContaining("Martin");
+		authors.forEach(author -> System.out.printf("streamAuthors(): author = %s%n", author));
+	}
+
 	private List<Author> insertAuthors() {
 		Author author1 = this.authorRepository.save(new Author(null, "Josh Long",
 				Set.of(new Book(null, "Reactive Spring"), new Book(null, "Cloud Native Java"))));