Reinstate auto-configuration support for embedded ActiveMQ

This commit restores auto-configuration for using an Embedded broker
with ActiveMQ classic.

Contrary to its 2.7.x version, "spring-boot-starter-activemq" no longer
adds the broker for consistency with Artemis, and to keep the existing
3.x behavior. Rather than "inMemory", a "s.a.embedded.enabled"
property has been reintroduced that matches the name used by Artemis.

The documentation has been updated to mention that the broker
dependency must be added to use it.

Closes gh-38404

spring-boot-tests/spring-boot-smoke-tests/spring-boot-smoke-test-activemq-embedded/build.gradle

@@ -0,0 +1,14 @@
+plugins {
+	id "java"
+	id "org.springframework.boot.conventions"
+}
+
+description = "Spring Boot Actuator ActiveMQ Embedded smoke test"
+
+dependencies {
+	implementation(project(":spring-boot-project:spring-boot-starters:spring-boot-starter-activemq"))
+
+	runtimeOnly("org.apache.activemq:activemq-broker")
+
+	testImplementation(project(":spring-boot-project:spring-boot-starters:spring-boot-starter-test"))
+}

spring-boot-tests/spring-boot-smoke-tests/spring-boot-smoke-test-activemq-embedded/src/main/java/smoketest/activemq/embedded/Consumer.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2012-2024 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 smoketest.activemq.embedded;
+
+import org.springframework.jms.annotation.JmsListener;
+import org.springframework.stereotype.Component;
+
+@Component
+public class Consumer {
+
+	@JmsListener(destination = "sample.queue")
+	public void receiveQueue(String text) {
+		System.out.println(text);
+	}
+
+}

spring-boot-tests/spring-boot-smoke-tests/spring-boot-smoke-test-activemq-embedded/src/main/java/smoketest/activemq/embedded/Producer.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2012-2024 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 smoketest.activemq.embedded;
+
+import jakarta.jms.Queue;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.jms.core.JmsMessagingTemplate;
+import org.springframework.stereotype.Component;
+
+@Component
+public class Producer implements CommandLineRunner {
+
+	@Autowired
+	private JmsMessagingTemplate jmsMessagingTemplate;
+
+	@Autowired
+	private Queue queue;
+
+	@Override
+	public void run(String... args) throws Exception {
+		send("Sample message");
+		System.out.println("Message was sent to the Queue");
+	}
+
+	public void send(String msg) {
+		this.jmsMessagingTemplate.convertAndSend(this.queue, msg);
+	}
+
+}

spring-boot-tests/spring-boot-smoke-tests/spring-boot-smoke-test-activemq-embedded/src/main/java/smoketest/activemq/embedded/SampleActiveMQApplication.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2012-2024 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 smoketest.activemq.embedded;
+
+import jakarta.jms.Queue;
+import org.apache.activemq.command.ActiveMQQueue;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Bean;
+import org.springframework.jms.annotation.EnableJms;
+
+@SpringBootApplication
+@EnableJms
+public class SampleActiveMQApplication {
+
+	@Bean
+	public Queue queue() {
+		return new ActiveMQQueue("sample.queue");
+	}
+
+	public static void main(String[] args) {
+		SpringApplication.run(SampleActiveMQApplication.class, args);
+	}
+
+}

spring-boot-tests/spring-boot-smoke-tests/spring-boot-smoke-test-activemq-embedded/src/test/java/smoketest/activemq/embedded/SampleActiveMQApplicationTests.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2012-2024 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 smoketest.activemq.embedded;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.system.CapturedOutput;
+import org.springframework.boot.test.system.OutputCaptureExtension;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Integration tests for ActiveMQ smoke test with embedded broker.
+ *
+ * @author Stephane Nicoll
+ */
+@SpringBootTest
+@ExtendWith(OutputCaptureExtension.class)
+class SampleActiveMQApplicationTests {
+
+	@Autowired
+	private Producer producer;
+
+	@Test
+	void sendSimpleMessage(CapturedOutput output) throws InterruptedException {
+		this.producer.send("Test message");
+		Thread.sleep(1000L);
+		assertThat(output).contains("Test message");
+	}
+
+}