RabbitMQ学习之spring-amqp的重要类的认识

潇洒紫焰

　　对于大多数应用来说都做了与spring整合，对于rabbitmq来说。也有与spring的整合。可能通过spring的官网找到spring-amqp项目下载。spring-amqp项目包括三个子项目：spring-amqp、spring-erlang、spring-rabbit.
　　下面来认识一下spring-amqp中的几个重要类；以spring-amqp-1.0.0.M3版本为例
　　1、Message : Spring AMQP定义的Message类是AMQP域模型中代表之一。Message类封装了body(消息BODY)和properties（消息属性） 。使得这个API看起来很简单。Message类定义如下：



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• public class Message {   
  
•     private final MessageProperties messageProperties;   
  
• 
  
•     private final byte[] body;   
  
• 
  
•     public Message(byte[] body, MessageProperties messageProperties) {   
  
•         this.body = body;   
  
•         this.messageProperties = messageProperties;   
  
•     }
  
• 
  
•     public byte[] getBody() {   
  
•         return this.body;   
  
•     }
  
• 
  
•     public MessageProperties getMessageProperties() {   
  
•         return this.messageProperties;   
  
•     }
  
• 
  
•     }
  

　　其中MessageProperties类中定义了例如messageId、timestamp、contentType等属性。这此属性可以扩展到用户通过setHeader(String key, Object value)方法来自定义“headers”。
　　2、Exchange
      Exchange接口代表一个AMQP的Exchange，决定消息生产者发送消息。每个Exchange都包括一个特定的唯一名字的虚拟主机的代理和一些其他属性。



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• public interface Exchange {   
  
• 
  
•     String getName();
  
• 
  
•     String getType();
  
• 
  
•     boolean isDurable();   
  
• 
  
•     boolean isAutoDelete();   
  
• 
  
•     Map<String, Object> getArguments();
  
• 
  
• }
  

　　其中 AbstractExchange类实现了Exchange类。而DirectExchange、TopicExchange、FanoutExchang、HeadersExchange四个类继承AbstractExchange。并重写了getType()类。根据各自相对应的Exchange类型。DirectExchange、TopicExchange、FanoutExchang、HeadersExchange分别对应的类型为direct,topic,fanout,headers.
　　3、Queue
Queue类是消息消费者接收消息中重要的一个组成部分。通过与Exchange判定来肯定消费者所接收的消息。伪代码如下：



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• public class Queue {   
  
•     private final String name;   
  
•     private volatile boolean durable;   
  
•     private volatile boolean exclusive;   
  
•     private volatile boolean autoDelete;   
  
•     private volatile Map<String, Object> arguments;   
  
•     public Queue(String name) {   
  
•     this.name = name;   
  
• }
  

　　其中name表示队列的名称、durable表示持久性。true表示是。exclusive表示独占性。由于在AmqpTemplate中提供一个方法来得到唯一的队列。这个队列可能是一个”reply-to“地址或者其他信息，因此一般exclusive和autoDelete一般设定为true.
　　4、Binding
     Bingding类通过多种构造参数来判定Exchange,Queue,routingkey;例如



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• Binding(Queue queue, FanoutExchange exchange)
  
• Binding(Queue queue, HeadersExchange exchange, Map<String, Object> arguments)
  
• Binding(Queue queue, DirectExchange exchange)
  
• Binding(Queue queue, DirectExchange exchange, String routingKey)
  
• Binding(Queue queue, TopicExchange exchange, String routingKey)
  

　　5、AmqpTemplate
AmqpTemplate是用来发送消息的模板类



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• /**
  
• * Specifies a basic set of AMQP operations.
  
• *  
  
• * Provides synchronous send and receive methods. The {@link #convertAndSend(Object)} and {@link #receiveAndConvert()}
  
• * methods allow let you send and receive POJO objects. Implementations are expected to delegate to an instance of
  
• * {@link MessageConverter} to perform conversion to and from AMQP byte[] payload type.
  
• *  
  
• * @author Mark Pollack
  
• * @author Mark Fisher
  
• */  
  
• public interface AmqpTemplate {  
  
• 
  
•     // send methods for messages  
  
• 
  
•     /**
  
•      * Send a message to a default exchange with a default routing key.
  
•      *  
  
•      * @param message a message to send
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     void send(Message message) throws AmqpException;  
  
• 
  
•     /**
  
•      * Send a message to a default exchange with a specific routing key.
  
•      *  
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     void send(String routingKey, Message message) throws AmqpException;  
  
• 
  
•     /**
  
•      * Send a message to a specific exchange with a specific routing key.
  
•      *  
  
•      * @param exchange the name of the exchange
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     void send(String exchange, String routingKey, Message message) throws AmqpException;  
  
• 
  
•     // send methods with conversion  
  
• 
  
•     /**
  
•      * Convert a Java object to an Amqp {@link Message} and send it to a default exchange with a default routing key.
  
•      *  
  
•      * @param message a message to send
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     void convertAndSend(Object message) throws AmqpException;  
  
• 
  
•     /**
  
•      * Convert a Java object to an Amqp {@link Message} and send it to a default exchange with a specific routing key.
  
•      *  
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     void convertAndSend(String routingKey, Object message) throws AmqpException;  
  
• 
  
•     /**
  
•      * Convert a Java object to an Amqp {@link Message} and send it to a specific exchange with a specific routing key.
  
•      *  
  
•      * @param exchange the name of the exchange
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     void convertAndSend(String exchange, String routingKey, Object message) throws AmqpException;  
  
• 
  
•     /**
  
•      * Convert a Java object to an Amqp {@link Message} and send it to a default exchange with a default routing key.
  
•      *  
  
•      * @param message a message to send
  
•      * @param messagePostProcessor a processor to apply to the message before it is sent
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     void convertAndSend(Object message, MessagePostProcessor messagePostProcessor) throws AmqpException;  
  
• 
  
•     /**
  
•      * Convert a Java object to an Amqp {@link Message} and send it to a default exchange with a specific routing key.
  
•      *  
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @param messagePostProcessor a processor to apply to the message before it is sent
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     void convertAndSend(String routingKey, Object message, MessagePostProcessor messagePostProcessor)  
  
•             throws AmqpException;  
  
• 
  
•     /**
  
•      * Convert a Java object to an Amqp {@link Message} and send it to a specific exchange with a specific routing key.
  
•      *  
  
•      * @param exchange the name of the exchange
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @param messagePostProcessor a processor to apply to the message before it is sent
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     void convertAndSend(String exchange, String routingKey, Object message, MessagePostProcessor messagePostProcessor)  
  
•             throws AmqpException;  
  
• 
  
•     // receive methods for messages  
  
• 
  
•     /**
  
•      * Receive a message if there is one from a default queue. Returns immediately, possibly with a null value.
  
•      *  
  
•      * @return a message or null if there is none waiting
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Message receive() throws AmqpException;  
  
• 
  
•     /**
  
•      * Receive a message if there is one from a specific queue. Returns immediately, possibly with a null value.
  
•      *  
  
•      * @param queueName the name of the queue to poll
  
•      * @return a message or null if there is none waiting
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Message receive(String queueName) throws AmqpException;  
  
• 
  
•     // receive methods with conversion  
  
• 
  
•     /**
  
•      * Receive a message if there is one from a default queue and convert it to a Java object. Returns immediately,
  
•      * possibly with a null value.
  
•      *  
  
•      * @return a message or null if there is none waiting
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Object receiveAndConvert() throws AmqpException;  
  
• 
  
•     /**
  
•      * Receive a message if there is one from a specific queue and convert it to a Java object. Returns immediately,
  
•      * possibly with a null value.
  
•      *  
  
•      * @param queueName the name of the queue to poll
  
•      * @return a message or null if there is none waiting
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Object receiveAndConvert(String queueName) throws AmqpException;  
  
• 
  
•     // send and receive methods for messages  
  
• 
  
•     /**
  
•      * Basic RPC pattern. Send a message to a default exchange with a default routing key and attempt to receive a
  
•      * response. Implementations will normally set the reply-to header to an exclusive queue and wait up for some time
  
•      * limited by a timeout.
  
•      *  
  
•      * @param message a message to send
  
•      * @return the response if there is one
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Message sendAndReceive(Message message) throws AmqpException;  
  
• 
  
•     /**
  
•      * Basic RPC pattern. Send a message to a default exchange with a specific routing key and attempt to receive a
  
•      * response. Implementations will normally set the reply-to header to an exclusive queue and wait up for some time
  
•      * limited by a timeout.
  
•      *  
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @return the response if there is one
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Message sendAndReceive(String routingKey, Message message) throws AmqpException;  
  
• 
  
•     /**
  
•      * Basic RPC pattern. Send a message to a specific exchange with a specific routing key and attempt to receive a
  
•      * response. Implementations will normally set the reply-to header to an exclusive queue and wait up for some time
  
•      * limited by a timeout.
  
•      *  
  
•      * @param exchange the name of the exchange
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @return the response if there is one
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Message sendAndReceive(String exchange, String routingKey, Message message) throws AmqpException;  
  
• 
  
•     // send and receive methods with conversion  
  
• 
  
•     /**
  
•      * Basic RPC pattern with conversion. Send a Java object converted to a message to a default exchange with a default
  
•      * routing key and attempt to receive a response, converting that to a Java object. Implementations will normally
  
•      * set the reply-to header to an exclusive queue and wait up for some time limited by a timeout.
  
•      *  
  
•      * @param message a message to send
  
•      * @return the response if there is one
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Object convertSendAndReceive(Object message) throws AmqpException;  
  
• 
  
•     /**
  
•      * Basic RPC pattern with conversion. Send a Java object converted to a message to a default exchange with a
  
•      * specific routing key and attempt to receive a response, converting that to a Java object. Implementations will
  
•      * normally set the reply-to header to an exclusive queue and wait up for some time limited by a timeout.
  
•      *  
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @return the response if there is one
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Object convertSendAndReceive(String routingKey, Object message) throws AmqpException;  
  
• 
  
•     /**
  
•      * Basic RPC pattern with conversion. Send a Java object converted to a message to a specific exchange with a
  
•      * specific routing key and attempt to receive a response, converting that to a Java object. Implementations will
  
•      * normally set the reply-to header to an exclusive queue and wait up for some time limited by a timeout.
  
•      *  
  
•      * @param exchange the name of the exchange
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @return the response if there is one
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Object convertSendAndReceive(String exchange, String routingKey, Object message) throws AmqpException;  
  
• 
  
•     /**
  
•      * Basic RPC pattern with conversion. Send a Java object converted to a message to a default exchange with a default
  
•      * routing key and attempt to receive a response, converting that to a Java object. Implementations will normally
  
•      * set the reply-to header to an exclusive queue and wait up for some time limited by a timeout.
  
•      *  
  
•      * @param message a message to send
  
•      * @param messagePostProcessor a processor to apply to the message before it is sent
  
•      * @return the response if there is one
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Object convertSendAndReceive(Object message, MessagePostProcessor messagePostProcessor) throws AmqpException;  
  
• 
  
•     /**
  
•      * Basic RPC pattern with conversion. Send a Java object converted to a message to a default exchange with a
  
•      * specific routing key and attempt to receive a response, converting that to a Java object. Implementations will
  
•      * normally set the reply-to header to an exclusive queue and wait up for some time limited by a timeout.
  
•      *  
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @param messagePostProcessor a processor to apply to the message before it is sent
  
•      * @return the response if there is one
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Object convertSendAndReceive(String routingKey, Object message, MessagePostProcessor messagePostProcessor) throws AmqpException;  
  
• 
  
•     /**
  
•      * Basic RPC pattern with conversion. Send a Java object converted to a message to a specific exchange with a
  
•      * specific routing key and attempt to receive a response, converting that to a Java object. Implementations will
  
•      * normally set the reply-to header to an exclusive queue and wait up for some time limited by a timeout.
  
•      *  
  
•      * @param exchange the name of the exchange
  
•      * @param routingKey the routing key
  
•      * @param message a message to send
  
•      * @param messagePostProcessor a processor to apply to the message before it is sent
  
•      * @return the response if there is one
  
•      * @throws AmqpException if there is a problem
  
•      */  
  
•     Object convertSendAndReceive(String exchange, String routingKey, Object message, MessagePostProcessor messagePostProcessor) throws AmqpException;  
  
• }
  

　　
6、AmqpAdmin和RabbitAdmin
   用户配置Queue、Exchange、Binding的代理类。代理类会自动声明或创建这些配置信息。
下面这个类用于异步接收消息的处理类
7、MessageConverter 消息转换器类
　　8、SimpleMessageListenerContainer 监听消息容器类
　　spring-amqp:
　　http://projects.spring.io/spring-amqp/
　　https://github.com/spring-projects/spring-amqp-samples
　　
转载：http://wubin850219.iteye.com/blog/1050251