2. Introduction

While the default Spring Framework version dependency is 4.3.x, Spring AMQP is generally compatible with earlier versions of Spring Framework. Annotation-based listeners and the RabbitMessagingTemplate require Spring Framework 4.1 or higher, however.

The minimum amqp-client java client library version is 4.0.0.

Note the this refers to the java client library; generally, it will work with older broker versions.

Using plain, imperative Java to send and receive a message:

ConnectionFactory connectionFactory = new CachingConnectionFactory();
AmqpAdmin admin = new RabbitAdmin(connectionFactory);
admin.declareQueue(new Queue("myqueue"));
AmqpTemplate template = new RabbitTemplate(connectionFactory);
template.convertAndSend("myqueue", "foo");
String foo = (String) template.receiveAndConvert("myqueue");

Note that there is a ConnectionFactory in the native Java Rabbit client as well. We are using the Spring abstraction in the code above. We are relying on the default exchange in the broker (since none is specified in the send), and the default binding of all queues to the default exchange by their name (hence we can use the queue name as a routing key in the send). Those behaviours are defined in the AMQP specification.

The same example as above, but externalizing the resource configuration to XML:

ApplicationContext context =
    new GenericXmlApplicationContext("classpath:/rabbit-context.xml");
AmqpTemplate template = context.getBean(AmqpTemplate.class);
template.convertAndSend("myqueue", "foo");
String foo = (String) template.receiveAndConvert("myqueue");

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:rabbit="http://www.springframework.org/schema/rabbit"
       xsi:schemaLocation="http://www.springframework.org/schema/rabbit
           http://www.springframework.org/schema/rabbit/spring-rabbit.xsd
           http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans.xsd">

    <rabbit:connection-factory id="connectionFactory"/>

    <rabbit:template id="amqpTemplate" connection-factory="connectionFactory"/>

    <rabbit:admin connection-factory="connectionFactory"/>

    <rabbit:queue name="myqueue"/>

</beans>

The <rabbit:admin/> declaration by default automatically looks for beans of type Queue, Exchange and Binding and declares them to the broker on behalf of the user, hence there is no need to use that bean explicitly in the simple Java driver. There are plenty of options to configure the properties of the components in the XML schema - you can use auto-complete features of your XML editor to explore them and look at their documentation.

The same example again with the external configuration in Java:

ApplicationContext context =
    new AnnotationConfigApplicationContext(RabbitConfiguration.class);
AmqpTemplate template = context.getBean(AmqpTemplate.class);
template.convertAndSend("myqueue", "foo");
String foo = (String) template.receiveAndConvert("myqueue");

........

@Configuration
public class RabbitConfiguration {

    @Bean
    public ConnectionFactory connectionFactory() {
        return new CachingConnectionFactory("localhost");
    }

    @Bean
    public AmqpAdmin amqpAdmin() {
        return new RabbitAdmin(connectionFactory());
    }

    @Bean
    public RabbitTemplate rabbitTemplate() {
        return new RabbitTemplate(connectionFactory());
    }

    @Bean
    public Queue myQueue() {
       return new Queue("myqueue");
    }
}

Spring AMQP now uses the new 4.0.x version of the amqp-client library provided by the RabbitMQ team. This client has auto recovery configured by default; see the section called “RabbitMQ Automatic Connection/Topology recovery”.

The minimum Log4j2 version (for the AmqpAppender) is now 2.7. The framework is no longer compatible with previous versions. See Section 3.2, “Logging Subsystem AMQP Appenders” for more information.

The minimum Spring Retry version is now 1.2. The framework is no longer compatible with previous versions.

The minimum Jackson version is now 2.8. The framework is no longer compatible with previous versions.

Rules that have up until now been used internally by the framework have now been made available in a separate jar spring-rabbit-junit. See Section 3.4.4, “JUnit @Rules” for more information.

When using an external transaction manager (e.g. JDBC), rule-based rollback is now supported when providing the container with a transaction attribute. It is also now more flexible when using a transaction advice.

A new ConnectionNameStrategy is now provided to populate the application-specific identification of the target RabbitMQ connection from the AbstractConnectionFactory. See Section 3.1.2, “Connection and Resource Management” for more information.