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本文主要研究一下rocketmq的ListenerContainerConfiguration
ListenerContainerConfiguration
rocketmq-spring-boot-2.0.3-sources.jar!/org/apache/rocketmq/spring/autoconfigure/ListenerContainerConfiguration.java
@Configuration
public class ListenerContainerConfiguration implements ApplicationContextAware, SmartInitializingSingleton {
private final static Logger log = LoggerFactory.getLogger(ListenerContainerConfiguration.class);
private ConfigurableApplicationContext applicationContext;
private AtomicLong counter = new AtomicLong(0);
private StandardEnvironment environment;
private RocketMQProperties rocketMQProperties;
private ObjectMapper objectMapper;
public ListenerContainerConfiguration(ObjectMapper rocketMQMessageObjectMapper,
StandardEnvironment environment,
RocketMQProperties rocketMQProperties) {
this.objectMapper = rocketMQMessageObjectMapper;
this.environment = environment;
this.rocketMQProperties = rocketMQProperties;
}
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
this.applicationContext = (ConfigurableApplicationContext) applicationContext;
}
@Override
public void afterSingletonsInstantiated() {
Map beans = this.applicationContext.getBeansWithAnnotation(RocketMQMessageListener.class);
if (Objects.nonNull(beans)) {
beans.forEach(this::registerContainer);
}
}
private void registerContainer(String beanName, Object bean) {
Class clazz = AopProxyUtils.ultimateTargetClass(bean);
if (!RocketMQListener.class.isAssignableFrom(bean.getClass())) {
throw new IllegalStateException(clazz + " is not instance of " + RocketMQListener.class.getName());
}
RocketMQMessageListener annotation = clazz.getAnnotation(RocketMQMessageListener.class);
validate(annotation);
String containerBeanName = String.format("%s_%s", DefaultRocketMQListenerContainer.class.getName(),
counter.incrementAndGet());
GenericApplicationContext genericApplicationContext = (GenericApplicationContext) applicationContext;
genericApplicationContext.registerBean(containerBeanName, DefaultRocketMQListenerContainer.class,
() -> createRocketMQListenerContainer(containerBeanName, bean, annotation));
DefaultRocketMQListenerContainer container = genericApplicationContext.getBean(containerBeanName,
DefaultRocketMQListenerContainer.class);
if (!container.isRunning()) {
try {
container.start();
} catch (Exception e) {
log.error("Started container failed. {}", container, e);
throw new RuntimeException(e);
}
}
log.info("Register the listener to container, listenerBeanName:{}, containerBeanName:{}", beanName, containerBeanName);
}
private DefaultRocketMQListenerContainer createRocketMQListenerContainer(String name, Object bean, RocketMQMessageListener annotation) {
DefaultRocketMQListenerContainer container = new DefaultRocketMQListenerContainer();
String nameServer = environment.resolvePlaceholders(annotation.nameServer());
nameServer = StringUtils.isEmpty(nameServer) ? rocketMQProperties.getNameServer() : nameServer;
String accessChannel = environment.resolvePlaceholders(annotation.accessChannel());
container.setNameServer(nameServer);
if (!StringUtils.isEmpty(accessChannel)) {
container.setAccessChannel(AccessChannel.valueOf(accessChannel));
}
container.setTopic(environment.resolvePlaceholders(annotation.topic()));
container.setConsumerGroup(environment.resolvePlaceholders(annotation.consumerGroup()));
container.setRocketMQMessageListener(annotation);
container.setRocketMQListener((RocketMQListener) bean);
container.setObjectMapper(objectMapper);
container.setName(name); // REVIEW ME, use the same clientId or multiple?
return container;
}
private void validate(RocketMQMessageListener annotation) {
if (annotation.consumeMode() == ConsumeMode.ORDERLY &&
annotation.messageModel() == MessageModel.BROADCASTING) {
throw new BeanDefinitionValidationException(
"Bad annotation definition in @RocketMQMessageListener, messageModel BROADCASTING does not support ORDERLY message!");
}
}
} - ListenerContainerConfiguration实现了ApplicationContextAware、SmartInitializingSingleton接口
- 其setApplicationContext方法保存了applicationContext；其afterSingletonsInstantiated方法会获取标注了RocketMQMessageListener注解的bean，然后挨个执行registerContainer
- registerContainer方法首先判断该bean是否是RocketMQListener的实现类，不是则抛出IllegalStateException；接着获取RocketMQMessageListener注解的信息，判断是否设置了不支持的属性；之后通过createRocketMQListenerContainer创建DefaultRocketMQListenerContainer并注册到applicationContext，然后对于没有running的container执行start方法
RocketMQMessageListener
rocketmq-spring-boot-2.0.3-sources.jar!/org/apache/rocketmq/spring/annotation/RocketMQMessageListener.java
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface RocketMQMessageListener {
String NAME_SERVER_PLACEHOLDER = "${rocketmq.name-server:}";
String ACCESS_KEY_PLACEHOLDER = "${rocketmq.consumer.access-key:}";
String SECRET_KEY_PLACEHOLDER = "${rocketmq.consumer.secret-key:}";
String TRACE_TOPIC_PLACEHOLDER = "${rocketmq.consumer.customized-trace-topic:}";
String ACCESS_CHANNEL_PLACEHOLDER = "${rocketmq.access-channel:}";
/**
* Consumers of the same role is required to have exactly same subscriptions and consumerGroup to correctly achieve
* load balance. It's required and needs to be globally unique.
*
*
* See here for further discussion.
*/
String consumerGroup();
/**
* Topic name.
*/
String topic();
/**
* Control how to selector message.
*
* @see SelectorType
*/
SelectorType selectorType() default SelectorType.TAG;
/**
* Control which message can be select. Grammar please see {@link SelectorType#TAG} and {@link SelectorType#SQL92}
*/
String selectorExpression() default "*";
/**
* Control consume mode, you can choice receive message concurrently or orderly.
*/
ConsumeMode consumeMode() default ConsumeMode.CONCURRENTLY;
/**
* Control message mode, if you want all subscribers receive message all message, broadcasting is a good choice.
*/
MessageModel messageModel() default MessageModel.CLUSTERING;
/**
* Max consumer thread number.
*/
int consumeThreadMax() default 64;
/**
* Max consumer timeout, default 30s.
*/
long consumeTimeout() default 30000L;
/**
* The property of "access-key".
*/
String accessKey() default ACCESS_KEY_PLACEHOLDER;
/**
* The property of "secret-key".
*/
String secretKey() default SECRET_KEY_PLACEHOLDER;
/**
* Switch flag instance for message trace.
*/
boolean enableMsgTrace() default true;
/**
* The name value of message trace topic.If you don't config,you can use the default trace topic name.
*/
String customizedTraceTopic() default TRACE_TOPIC_PLACEHOLDER;
/**
* The property of "name-server".
*/
String nameServer() default NAME_SERVER_PLACEHOLDER;
/**
* The property of "access-channel".
*/
String accessChannel() default ACCESS_CHANNEL_PLACEHOLDER;
}- RocketMQMessageListener注解定义了consumerGroup、topic、selectorType、selectorExpression、consumeMode、messageModel、consumeThreadMax、consumeTimeout、accessKey、secretKey、enableMsgTrace、customizedTraceTopic、nameServer、accessChannel属性
小结
- ListenerContainerConfiguration实现了ApplicationContextAware、SmartInitializingSingleton接口
- 其setApplicationContext方法保存了applicationContext；其afterSingletonsInstantiated方法会获取标注了RocketMQMessageListener注解的bean，然后挨个执行registerContainer
- registerContainer方法首先判断该bean是否是RocketMQListener的实现类，不是则抛出IllegalStateException；接着获取RocketMQMessageListener注解的信息，判断是否设置了不支持的属性；之后通过createRocketMQListenerContainer创建DefaultRocketMQListenerContainer并注册到applicationContext，然后对于没有running的container执行start方法
doc
- ListenerContainerConfiguration