spring - 如何使用Spring Boot JMS收听主题

Question

我正在尝试使用以下代码段收听主题。但是，默认情况下，其监听队列。在这种情况下，没有xml配置。我完全依靠注释。此外，我完全依赖于Spring boot提供的AutoConfiguration。我不确定如何在JmsListener中将目标类型设置为主题。 Spring JMS专家请帮忙。

    @Component
    public class MyTopicListener {

        @JmsListener(destination = "${trans.alert.topic}")
        public void receiveMessage(TransactionAlert alert) {
            logger.info("AlertSubscriberEmail :: Sending Email => <" + alert + ">");
        }
    }

Answer 1

我只是从以下示例中获取了完整的Spring引导示例:https://github.com/spring-guides/gs-messaging-jms/

在此创建用于从队列发送和接收消息。要将其更改为主题，必须在Factory实例中设置Pub-Sub属性。

import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jms.DefaultJmsListenerContainerFactoryConfigurer;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.jms.annotation.EnableJms;
import org.springframework.jms.config.DefaultJmsListenerContainerFactory;
import org.springframework.jms.config.JmsListenerContainerFactory;
import org.springframework.jms.connection.CachingConnectionFactory;
import org.springframework.jms.core.JmsTemplate;
import org.springframework.jms.support.converter.MappingJackson2MessageConverter;
import org.springframework.jms.support.converter.MessageConverter;
import org.springframework.jms.support.converter.MessageType;

import javax.jms.ConnectionFactory;

@SpringBootApplication
@EnableJms
public class JmsSampleApplication {

public void registerBeans(ConfigurableApplicationContext context ){
    BeanDefinitionBuilder builder = BeanDefinitionBuilder.rootBeanDefinition(JmsTemplate.class);
    CachingConnectionFactory cachingConnectionFactory = new CachingConnectionFactory();

    builder.addPropertyValue("connectionFactory", cachingConnectionFactory);      // set property value
    DefaultListableBeanFactory factory = (DefaultListableBeanFactory) context.getAutowireCapableBeanFactory();
    factory.registerBeanDefinition("jmsTemplateName", builder.getBeanDefinition());
}

@Bean
public JmsListenerContainerFactory<?> topicListenerFactory(ConnectionFactory connectionFactory,
                                                DefaultJmsListenerContainerFactoryConfigurer configurer) {
    DefaultJmsListenerContainerFactory factory = new DefaultJmsListenerContainerFactory();
    factory.setPubSubDomain(true);
    // This provides all boot's default to this factory, including the message converter
    configurer.configure(factory, connectionFactory);
    // You could still override some of Boot's default if necessary.
    return factory;
}

@Bean
public JmsListenerContainerFactory<?> queueListenerFactory(ConnectionFactory connectionFactory,
                                                           DefaultJmsListenerContainerFactoryConfigurer configurer) {
    DefaultJmsListenerContainerFactory factory = new DefaultJmsListenerContainerFactory();
    //factory.setPubSubDomain(true);
    // This provides all boot's default to this factory, including the message converter
    configurer.configure(factory, connectionFactory);
    return factory;
}

@Bean // Serialize message content to json using TextMessage
public MessageConverter jacksonJmsMessageConverter() {
    MappingJackson2MessageConverter converter = new MappingJackson2MessageConverter();
    converter.setTargetType(MessageType.TEXT);
    converter.setTypeIdPropertyName("_type");
    return converter;
}
public static void main(String[] args) {
    ConfigurableApplicationContext context = SpringApplication.run(JmsSampleApplication.class, args);

    JmsTemplate jmsTemplate = context.getBean(JmsTemplate.class);

    // Send a message with a POJO - the template reuse the message converter
    System.out.println("Sending an email message.");
    jmsTemplate.convertAndSend("mailbox.topic", new Email("info@example.com", "Hello"));
    jmsTemplate.convertAndSend("mailbox.queue", new Email("info@example.com", "Hello"));

    }
}

监听器

package org.springboot.jms;

import org.springframework.jms.annotation.JmsListener;
import org.springframework.stereotype.Component;

/**
 * Created by RGOVIND on 10/20/2016.
 */
@Component
public class HelloTopicListener {

    @JmsListener(destination = "mailbox.topic", containerFactory = "topicListenerFactory")
    public void receiveTopicMessage(Email email) {
        System.out.println("Received <" + email + ">");
    }

    @JmsListener(destination = "mailbox.queue", containerFactory = "queueListenerFactory")
    public void receiveQueueMessage(Email email) {
        System.out.println("Received <" + email + ">");
    }
}

完成此操作后，您就可以全部订阅所选的主题。

当然，有多种方法，您可以为不同的jmsTemplates提供一个bean映射，当您基于队列或主题需要它们时可以使用每种bean。可以使用您喜欢的此 SO Question中讨论的方法来实例化模板和bean。希望能帮助到你