RabbitMQ案例七之RPC远程过程调用

目的：到服务器请求数据

Client的代码如下：

package yy.rabbitstudy.rpc;import com.rabbitmq.client.AMQP.BasicProperties;import com.rabbitmq.client.Channel;import com.rabbitmq.client.QueueingConsumer;import yy.rabbitstudy.util.RabbitMQUtil;public class RPCClient {    private Channel channel;    private String requestQueueName = "rpc_queue";    private String replyQueueName;    private QueueingConsumer consumer;    public RPCClient() throws Exception {        channel=RabbitMQUtil.getChannel();        replyQueueName = channel.queueDeclare().getQueue();         consumer = new QueueingConsumer(channel);        channel.basicConsume(replyQueueName, true, consumer);    }    public String call(String message) throws Exception {             String response = null;        String corrId = java.util.UUID.randomUUID().toString();        BasicProperties props = new BasicProperties                                    .Builder()                                    .correlationId(corrId)                                    .replyTo(replyQueueName)                                    .build();        channel.basicPublish("", requestQueueName, props, message.getBytes());        while (true) {            QueueingConsumer.Delivery delivery = consumer.nextDelivery();            if (delivery.getProperties().getCorrelationId().equals(corrId)) {                response = new String(delivery.getBody());                break;            }        }        return response;     }    public static void main(String[] args) throws Exception {        RPCClient client=new RPCClient();        String response = client.call("15");        System.out.println(response);            }}

Server的代码如下：

package yy.rabbitstudy.rpc;import java.io.IOException;import com.rabbitmq.client.AMQP.BasicProperties;import com.rabbitmq.client.Channel;import com.rabbitmq.client.ConsumerCancelledException;import com.rabbitmq.client.QueueingConsumer;import com.rabbitmq.client.ShutdownSignalException;import yy.rabbitstudy.util.RabbitMQUtil;public class RPCServer {    private static final String RPC_QUEUE_NAME = "rpc_queue";    public static void main(String[] args) {        Channel channel = RabbitMQUtil.getChannel();        try {            channel.queueDeclare(RPC_QUEUE_NAME,false,false,false,null);            channel.basicQos(1);            QueueingConsumer consumer=new QueueingConsumer(channel);            channel.basicConsume(RPC_QUEUE_NAME, false, consumer);            System.out.println(" [x] Awaiting RPC requests");            while(true){                QueueingConsumer.Delivery delivery=consumer.nextDelivery();                BasicProperties properties = delivery.getProperties();                BasicProperties replyProps=new BasicProperties                        .Builder()                        .correlationId(properties.getCorrelationId())                        .build();                String message=new String(delivery.getBody());                int n=Integer.parseInt(message);                String response=""+fib(n);                channel.basicPublish("", properties.getReplyTo(), replyProps, response.getBytes());                channel.basicAck(delivery.getEnvelope().getDeliveryTag(), false);                                    }        } catch (IOException e) {            e.printStackTrace();        } catch (ShutdownSignalException e) {            // TODO Auto-generated catch block            e.printStackTrace();        } catch (ConsumerCancelledException e) {            // TODO Auto-generated catch block            e.printStackTrace();        } catch (InterruptedException e) {            // TODO Auto-generated catch block            e.printStackTrace();        }finally {            RabbitMQUtil.close();        }            }    private static int fib(int n) {        if (n == 0) return 0;        if (n == 1) return 1;        return fib(n-1) + fib(n-2);    }}