Add examples using Virtual Threads.

Closes #665

README.adoc

@@ -29,13 +29,16 @@ Local Elasticsearch instance must be running to run the tests.
 == Spring Data JPA
 
 * `eclipselink` - Sample project to show how to use Spring Data JPA with Spring Boot and https://www.eclipse.org/eclipselink/[Eclipselink].
-* `example` - Probably the project you want to have a look at first. Contains a variety of sample packages, showcasing the different levels at which you can use Spring Data JPA. Have a look at the `simple` package for the most basic setup.
+* `example` - Probably the project you want to have a look at first.
+Contains a variety of sample packages, showcasing the different levels at which you can use Spring Data JPA.
+Have a look at the `simple` package for the most basic setup.
+Contains also examples running on Virtual Threads.
 * `interceptors` - Example of how to enrich the repositories with AOP.
 * `jpa21` - Shows support for JPA 2.1 specific features (stored procedures support).
 * `multiple-datasources` - Examples of how to use Spring Data JPA with multiple `DataSource`s.
 * `query-by-example` - Example project showing usage of Query by Example with Spring Data JPA.
 * `security` - Example of how to integrate Spring Data JPA Repositories with Spring Security.
-* `showcase` - Refactoring show case of how to improve a plain-JPA-based persistence layer by using Spring Data JPA (read: removing close to all of the implementation code). Follow the `demo.txt` file for detailed instructions.
+* `showcase` - Refactoring show case of how to improve a plain-JPA-based persistence layer by using Spring Data JPA (read: removing close to all of the implementation code).Follow the `demo.txt` file for detailed instructions.
 * `vavr` - Shows the support of https://www.vavr.io[Vavr] collection types as return types for query methods.
 
 == Spring Data LDAP
@@ -72,6 +75,7 @@ Local Elasticsearch instance must be running to run the tests.
 
 * `cluster` - Example for Redis Cluster support.
 * `example` - Example for basic Spring Data Redis setup.
+* `pubsub` - Example project to show Pub/Sub usage using Platform and Virtual Threads.
 * `reactive` - Example project to show reactive template support.
 * `repositories` - Example demonstrating Spring Data repository abstraction on top of Redis.
 * `sentinel` - Example for Redis Sentinel support.

jpa/example/src/main/java/example/springdata/jpa/simple/SimpleConfiguration.java

@@ -16,9 +16,11 @@
 package example.springdata.jpa.simple;
 
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.scheduling.annotation.EnableAsync;
 
 /**
  * @author Oliver Gierke
  */
 @SpringBootApplication
+@EnableAsync
 class SimpleConfiguration {}

jpa/example/src/main/java/example/springdata/jpa/simple/SimpleUserRepository.java

@@ -24,7 +24,7 @@ import org.springframework.data.domain.Pageable;
 import org.springframework.data.domain.Slice;
 import org.springframework.data.domain.Sort;
 import org.springframework.data.jpa.repository.Query;
-import org.springframework.data.repository.CrudRepository;
+import org.springframework.data.repository.ListCrudRepository;
 import org.springframework.scheduling.annotation.Async;
 
 /**
@@ -35,7 +35,7 @@ import org.springframework.scheduling.annotation.Async;
  * @author Thomas Darimont
  * @author Christoph Strobl
  */
-public interface SimpleUserRepository extends CrudRepository<User, Long> {
+public interface SimpleUserRepository extends ListCrudRepository<User, Long> {
 
 	/**
 	 * Find the user with the given username. This method will be translated into a query using the

jpa/example/src/test/java/example/springdata/jpa/simple/VirtualThreadsTests.java

@@ -0,0 +1,114 @@
+/*
+ * Copyright 2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package example.springdata.jpa.simple;
+
+import static org.assertj.core.api.Assertions.*;
+
+import java.util.List;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.TimeUnit;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.condition.EnabledOnJre;
+import org.junit.jupiter.api.condition.JRE;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.core.task.SimpleAsyncTaskExecutor;
+import org.springframework.transaction.annotation.Propagation;
+import org.springframework.transaction.annotation.Transactional;
+
+/**
+ * Integration test showing the basic usage of {@link SimpleUserRepository} with Virtual Threads.
+ *
+ * @author Mark Paluch
+ */
+@Transactional
+@SpringBootTest(properties = "spring.threads.virtual.enabled=true")
+@EnabledOnJre(JRE.JAVA_21)
+class VirtualThreadsTests {
+
+	@Autowired SimpleUserRepository repository;
+	private User user;
+
+	@BeforeEach
+	void setUp() {
+
+		user = new User();
+		user.setUsername("foobar");
+		user.setFirstname("firstname");
+		user.setLastname("lastname");
+	}
+
+	/**
+	 * This repository invocation runs on a dedicated virtual thread.
+	 */
+	@Test
+	@Transactional(propagation = Propagation.NOT_SUPPORTED)
+	void supportsVirtualThreads() throws Exception {
+
+		BlockingQueue<String> thread = new LinkedBlockingQueue<>();
+		repository.save(new User("Customer1", "Foo"));
+		repository.save(new User("Customer2", "Bar"));
+
+		try (SimpleAsyncTaskExecutor executor = new SimpleAsyncTaskExecutor()) {
+			executor.setVirtualThreads(true);
+
+			var future = executor.submit(() -> {
+				thread.add(Thread.currentThread().toString());
+				return repository.findAll();
+			});
+
+			List<User> users = future.get();
+			String threadName = thread.poll(1, TimeUnit.SECONDS);
+
+			assertThat(threadName).contains("VirtualThread");
+			assertThat(users).hasSize(2);
+		}
+
+		repository.deleteAll();
+	}
+
+	/**
+	 * Here we demonstrate the usage of {@link CompletableFuture} as a result wrapper for asynchronous repository query
+	 * methods running on Virtual Threads. Note, that we need to disable the surrounding transaction to be able to
+	 * asynchronously read the written data from another thread within the same test method.
+	 */
+	@Test
+	@Transactional(propagation = Propagation.NOT_SUPPORTED)
+	void asyncUsesVirtualThreads() throws Exception {
+
+		BlockingQueue<String> thread = new LinkedBlockingQueue<>();
+		repository.save(new User("Customer1", "Foo"));
+		repository.save(new User("Customer2", "Bar"));
+
+		var future = repository.readAllBy().thenAccept(users -> {
+
+			assertThat(users).hasSize(2);
+			thread.add(Thread.currentThread().toString());
+		});
+
+		future.join();
+		String threadName = thread.poll(1, TimeUnit.SECONDS);
+
+		assertThat(threadName).contains("VirtualThread");
+
+		repository.deleteAll();
+	}
+}

redis/pom.xml

@@ -18,6 +18,7 @@
 	<modules>
 		<module>cluster</module>
 		<module>example</module>
+		<module>pubsub</module>
 		<module>reactive</module>
 		<module>repositories</module>
 		<module>sentinel</module>

redis/pubsub/README.md

@@ -0,0 +1,4 @@
+# Spring Data Redis Pub/Sub Example
+
+This project contains samples of specific features of Spring Data Redis.
+

redis/pubsub/pom.xml

@@ -0,0 +1,27 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+
+	<artifactId>spring-data-redis-pubsub</artifactId>
+	<name>Spring Data Redis - Pub/Sub</name>
+
+	<parent>
+		<groupId>org.springframework.data.examples</groupId>
+		<artifactId>spring-data-redis-examples</artifactId>
+		<version>2.0.0.BUILD-SNAPSHOT</version>
+		<relativePath>../pom.xml</relativePath>
+	</parent>
+
+	<dependencies>
+
+		<dependency>
+			<groupId>${project.groupId}</groupId>
+			<artifactId>spring-data-redis-example-utils</artifactId>
+			<version>${project.version}</version>
+			<scope>test</scope>
+		</dependency>
+
+	</dependencies>
+
+</project>

redis/pubsub/src/test/java/example/springdata/redis/PubSubTests.java

@@ -0,0 +1,109 @@
+/*
+ * Copyright 2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package example.springdata.redis;
+
+import static org.assertj.core.api.Assertions.*;
+
+import java.util.Collection;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.LinkedBlockingDeque;
+import java.util.concurrent.TimeUnit;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.data.redis.connection.RedisConnectionFactory;
+import org.springframework.data.redis.core.StringRedisTemplate;
+import org.springframework.data.redis.listener.ChannelTopic;
+import org.springframework.data.redis.listener.RedisMessageListenerContainer;
+import org.springframework.data.redis.listener.adapter.MessageListenerAdapter;
+import org.springframework.data.redis.serializer.StringRedisSerializer;
+
+/**
+ * Show usage of Redis Pub/Sub operations.
+ *
+ * @author Mark Paluch
+ */
+@SpringBootTest
+public class PubSubTests {
+
+	@Autowired RedisConnectionFactory connectionFactory;
+
+	@Autowired StringRedisTemplate redisTemplate;
+
+	@Test
+	void shouldListenToPubSubEvents() throws Exception {
+
+		BlockingQueue<String> events = new LinkedBlockingDeque<>();
+
+		RedisMessageListenerContainer container = new RedisMessageListenerContainer();
+		container.setConnectionFactory(connectionFactory);
+		container.afterPropertiesSet();
+		container.addMessageListener(
+				(message, pattern) -> events.add(String.format("%s@%s", new String(message.getBody()), new String(pattern))),
+				ChannelTopic.of("my-channel"));
+
+		container.start();
+
+		redisTemplate.convertAndSend("my-channel", "Hello, world!");
+
+		String event = events.poll(5, TimeUnit.SECONDS);
+
+		container.stop();
+		container.destroy();
+
+		assertThat(event).isEqualTo("Hello, world!@my-channel");
+	}
+
+	@Test
+	void shouldNotifyListener() throws Exception {
+
+		BlockingQueue<String> events = new LinkedBlockingDeque<>();
+
+		RedisMessageListenerContainer container = new RedisMessageListenerContainer();
+		container.setConnectionFactory(connectionFactory);
+		container.afterPropertiesSet();
+
+		MessageListenerAdapter messageListenerAdapter = new MessageListenerAdapter(new MyListener(events));
+		messageListenerAdapter.afterPropertiesSet();
+		messageListenerAdapter.setSerializer(StringRedisSerializer.UTF_8);
+		container.addMessageListener(messageListenerAdapter, ChannelTopic.of("my-channel"));
+
+		container.start();
+
+		redisTemplate.convertAndSend("my-channel", "Hello, world!");
+
+		String event = events.poll(5, TimeUnit.SECONDS);
+
+		container.stop();
+		container.destroy();
+
+		assertThat(event).isEqualTo("Hello, world!@my-channel");
+	}
+
+	static class MyListener {
+		private final Collection<String> events;
+
+		public MyListener(Collection<String> events) {
+			this.events = events;
+		}
+
+		public void handleMessage(String message, String channel) {
+			events.add(String.format("%s@%s", message, channel));
+		}
+	}
+}

redis/pubsub/src/test/java/example/springdata/redis/PubSubVirtualThreadsTests.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package example.springdata.redis;
+
+import static org.assertj.core.api.Assertions.*;
+
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.LinkedBlockingDeque;
+import java.util.concurrent.TimeUnit;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.condition.EnabledOnJre;
+import org.junit.jupiter.api.condition.JRE;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.core.task.AsyncTaskExecutor;
+import org.springframework.data.redis.connection.RedisConnectionFactory;
+import org.springframework.data.redis.core.StringRedisTemplate;
+import org.springframework.data.redis.listener.ChannelTopic;
+import org.springframework.data.redis.listener.RedisMessageListenerContainer;
+
+/**
+ * Show usage of Redis Pub/Sub operations using Virtual Threads.
+ *
+ * @author Mark Paluch
+ */
+@SpringBootTest(properties = "spring.threads.virtual.enabled=true")
+@EnabledOnJre(JRE.JAVA_21)
+public class PubSubVirtualThreadsTests {
+
+	@Autowired RedisConnectionFactory connectionFactory;
+
+	@Autowired AsyncTaskExecutor taskExecutor;
+
+	@Autowired StringRedisTemplate redisTemplate;
+
+	@Test
+	void shouldListenToPubSubEvents() throws Exception {
+
+		BlockingQueue<String> events = new LinkedBlockingDeque<>();
+
+		RedisMessageListenerContainer container = new RedisMessageListenerContainer();
+		container.setConnectionFactory(connectionFactory);
+		container.setTaskExecutor(taskExecutor);
+		container.afterPropertiesSet();
+		container.addMessageListener(
+				(message, pattern) -> events
+						.add(String.format("%s on Thread %s", new String(message.getBody()), Thread.currentThread())),
+				ChannelTopic.of("my-channel"));
+
+		container.start();
+
+		redisTemplate.convertAndSend("my-channel", "Hello, world!");
+
+		String event = events.poll(5, TimeUnit.SECONDS);
+
+		container.stop();
+		container.destroy();
+
+		assertThat(event).isNotNull().contains("Hello, world!").contains("VirtualThread");
+	}
+}

redis/pubsub/src/test/java/example/springdata/redis/RedisTestConfiguration.java

@@ -0,0 +1,24 @@
+/*
+ * Copyright 2014-2021 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package example.springdata.redis;
+
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+/**
+ * @author Mark Paluch
+ */
+@SpringBootApplication
+public class RedisTestConfiguration {}

redis/pubsub/src/test/resources/application.properties

@@ -0,0 +1 @@
+logging.level.root=WARN