覆盖 Boot 的侦听器容器工厂 bean,如 Enable Listener Endpoint Annotations 中所述。
@Bean
public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory() {
SimpleRabbitListenerContainerFactory factory = new SimpleRabbitListenerContainerFactory();
factory.setConnectionFactory(connectionFactory);
factory.setErrorHandler(myErrorHandler());
...
return factory;
}
您可以注入 ErrorHandler 的自定义实现,它将添加到工厂创建的每个侦听器容器中。
void handleError(Throwable t);
throwable 将是 ListenerExecutionFailedException,从版本 1.6.7(启动 1.4.4)开始,其 failedMessage 属性中包含原始入站消息。
默认错误处理程序认为MessageConversionException 等原因是致命的(它们不会被重新排队)。
如果您希望保留该行为(对于此类问题是正常的),您应该在处理错误后抛出AmqpRejectAndDontRequeueException。
顺便说一句,你不需要那个RabbitTemplate bean;如果您的应用程序中只有一个MessageConverter bean,启动会自动将其连接到容器和模板中。
由于您将覆盖引导的工厂,您将必须在那里连接转换器。
编辑
您可以使用默认的ConditionalRejectingErrorHandler,但使用FatalExceptionStrategy 的自定义实现注入它。实际上,您可以继承它的DefaultExceptionStrategy 并覆盖isFatal(Throwable t),然后在处理错误后返回super.isFatal(t)。
EDIT2
完整示例;发送 1 条好消息和 1 条坏消息:
package com.example;
import org.slf4j.Logger;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.core.Queue;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.amqp.rabbit.config.SimpleRabbitListenerContainerFactory;
import org.springframework.amqp.rabbit.connection.ConnectionFactory;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.amqp.rabbit.listener.ConditionalRejectingErrorHandler;
import org.springframework.amqp.rabbit.listener.exception.ListenerExecutionFailedException;
import org.springframework.amqp.support.converter.Jackson2JsonMessageConverter;
import org.springframework.amqp.support.converter.MessageConverter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.util.ErrorHandler;
@SpringBootApplication
public class So42215050Application {
public static void main(String[] args) throws Exception {
ConfigurableApplicationContext context = SpringApplication.run(So42215050Application.class, args);
context.getBean(So42215050Application.class).runDemo();
context.close();
}
@Autowired
private RabbitTemplate template;
private void runDemo() throws Exception {
this.template.convertAndSend(queue().getName(), new Foo("bar"));
this.template.convertAndSend(queue().getName(), new Foo("bar"), m -> {
return new Message("some bad json".getBytes(), m.getMessageProperties());
});
Thread.sleep(5000);
}
@RabbitListener(queues = "So42215050")
public void handle(Foo in) {
System.out.println("Received: " + in);
}
@Bean
public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory(ConnectionFactory connectionFactory) {
SimpleRabbitListenerContainerFactory factory = new SimpleRabbitListenerContainerFactory();
factory.setConnectionFactory(connectionFactory);
factory.setMessageConverter(jsonConverter());
factory.setErrorHandler(errorHandler());
return factory;
}
@Bean
public ErrorHandler errorHandler() {
return new ConditionalRejectingErrorHandler(new MyFatalExceptionStrategy());
}
@Bean
public Queue queue() {
return new Queue("So42215050", false, false, true);
}
@Bean
public MessageConverter jsonConverter() {
return new Jackson2JsonMessageConverter();
}
public static class MyFatalExceptionStrategy extends ConditionalRejectingErrorHandler.DefaultExceptionStrategy {
private final Logger logger = org.slf4j.LoggerFactory.getLogger(getClass());
@Override
public boolean isFatal(Throwable t) {
if (t instanceof ListenerExecutionFailedException) {
ListenerExecutionFailedException lefe = (ListenerExecutionFailedException) t;
logger.error("Failed to process inbound message from queue "
+ lefe.getFailedMessage().getMessageProperties().getConsumerQueue()
+ "; failed message: " + lefe.getFailedMessage(), t);
}
return super.isFatal(t);
}
}
public static class Foo {
private String foo;
public Foo() {
super();
}
public Foo(String foo) {
this.foo = foo;
}
public String getFoo() {
return this.foo;
}
public void setFoo(String foo) {
this.foo = foo;
}
@Override
public String toString() {
return "Foo [foo=" + this.foo + "]";
}
}
}
结果:
Received: Foo [foo=bar]
2017-02-14 09:42:50.972 错误 44868 --- [cTaskExecutor-1] 5050Application$MyFatalExceptionStrategy:无法处理来自队列 So42215050 的入站消息;失败的消息:(正文:'some bad json' MessageProperties [headers={TypeId=com.example.So42215050Application$Foo},timestamp=null,messageId=null,userId=null,receivedUserId=null, appId=null,clusterId=null,type=null,correlationId=null,correlationIdString=null,replyTo=null,contentType=application/json,contentEncoding=UTF-8,contentLength=0,deliveryMode=null,receivedDeliveryMode=PERSISTENT,expiration= null, priority=0, redelivered=false, receivedExchange=, receivedRoutingKey=So42215050, receivedDelay=null, deliveryTag=2, messageCount=0, consumerTag=amq.ctag-P2QqY0PMD1ppX5NnkUPhFA, consumerQueue=So42215050])
EDIT3
JSON 不传达任何类型信息。默认情况下,要转换的类型将从方法参数类型中推断出来。如果您希望拒绝任何无法转换为该类型的内容,则需要适当地配置消息转换器。
例如:
@Bean
public MessageConverter jsonConverter() {
Jackson2JsonMessageConverter converter = new Jackson2JsonMessageConverter();
DefaultClassMapper mapper = new DefaultClassMapper();
mapper.setDefaultType(Foo.class);
converter.setClassMapper(mapper);
return converter;
}
现在,当我将示例更改为发送 Bar 而不是 Foo...
public static class Bar {
...
}
和
this.template.convertAndSend(queue().getName(), new Bar("baz"));
我明白了……
Caused by: org.springframework.amqp.support.converter.MessageConversionException: Cannot handle message
... 13 common frames omitted
Caused by: org.springframework.messaging.converter.MessageConversionException: Cannot convert from [com.example.So42215050Application$Bar] to [com.example.So42215050Application$Foo] for GenericMessage [payload=Bar [foo=baz], headers={amqp_receivedDeliveryMode=PERSISTENT, amqp_receivedRoutingKey=So42215050, amqp_contentEncoding=UTF-8, amqp_deliveryTag=3, amqp_consumerQueue=So42215050, amqp_redelivered=false, id=6d7e23a3-c2a7-2417-49c9-69e3335aa485, amqp_consumerTag=amq.ctag-6JIGkpmkrTKaG32KVpf8HQ, contentType=application/json, __TypeId__=com.example.So42215050Application$Bar, timestamp=1488489538017}]
但这只有在发件人设置__TypeId__ 标头时才有效(如果模板配置了相同的适配器,则模板会这样做)。
EDIT4
@SpringBootApplication
public class So42215050Application {
private final Logger logger = org.slf4j.LoggerFactory.getLogger(getClass());
public static void main(String[] args) throws Exception {
ConfigurableApplicationContext context = SpringApplication.run(So42215050Application.class, args);
context.getBean(So42215050Application.class).runDemo();
context.close();
}
@Autowired
private RabbitTemplate template;
private void runDemo() throws Exception {
this.template.convertAndSend(queue().getName(), new Foo("bar")); // good - converter sets up type
this.template.convertAndSend(queue().getName(), new Foo("bar"), m -> {
return new Message("some bad json".getBytes(), m.getMessageProperties()); // fail bad json
});
Message message = MessageBuilder
.withBody("{\"foo\":\"bar\"}".getBytes())
.andProperties(
MessagePropertiesBuilder
.newInstance()
.setContentType("application/json")
.build())
.build();
this.template.send(queue().getName(), message); // Success - default Foo class when no header
message.getMessageProperties().setHeader("__TypeId__", "foo");
this.template.send(queue().getName(), message); // Success - foo is mapped to Foo
message.getMessageProperties().setHeader("__TypeId__", "bar");
this.template.send(queue().getName(), message); // fail - mapped to a Map
Thread.sleep(5000);
}
@RabbitListener(queues = "So42215050")
public void handle(Foo in) {
logger.info("Received: " + in);
}
@Bean
public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory(ConnectionFactory connectionFactory) {
SimpleRabbitListenerContainerFactory factory = new SimpleRabbitListenerContainerFactory();
factory.setConnectionFactory(connectionFactory);
factory.setMessageConverter(jsonConverter());
factory.setErrorHandler(errorHandler());
return factory;
}
@Bean
public ErrorHandler errorHandler() {
return new ConditionalRejectingErrorHandler(new MyFatalExceptionStrategy());
}
@Bean
public Queue queue() {
return new Queue("So42215050", false, false, true);
}
@Bean
public MessageConverter jsonConverter() {
Jackson2JsonMessageConverter converter = new Jackson2JsonMessageConverter();
DefaultClassMapper mapper = new DefaultClassMapper();
mapper.setDefaultType(Foo.class);
Map<String, Class<?>> mappings = new HashMap<>();
mappings.put("foo", Foo.class);
mappings.put("bar", Object.class);
mapper.setIdClassMapping(mappings);
converter.setClassMapper(mapper);
return converter;
}
public static class MyFatalExceptionStrategy extends ConditionalRejectingErrorHandler.DefaultExceptionStrategy {
private final Logger logger = org.slf4j.LoggerFactory.getLogger(getClass());
@Override
public boolean isFatal(Throwable t) {
if (t instanceof ListenerExecutionFailedException) {
ListenerExecutionFailedException lefe = (ListenerExecutionFailedException) t;
logger.error("Failed to process inbound message from queue "
+ lefe.getFailedMessage().getMessageProperties().getConsumerQueue()
+ "; failed message: " + lefe.getFailedMessage(), t);
}
return super.isFatal(t);
}
}
public static class Foo {
private String foo;
public Foo() {
super();
}
public Foo(String foo) {
this.foo = foo;
}
public String getFoo() {
return this.foo;
}
public void setFoo(String foo) {
this.foo = foo;
}
@Override
public String toString() {
return "Foo [foo=" + this.foo + "]";
}
}
public static class Bar {
private String foo;
public Bar() {
super();
}
public Bar(String foo) {
this.foo = foo;
}
public String getFoo() {
return this.foo;
}
public void setFoo(String foo) {
this.foo = foo;
}
@Override
public String toString() {
return "Bar [foo=" + this.foo + "]";
}
}
}