RabbitMQ学习之队列监控

对于RabbitMQ的监控，除了服务器基本信息（硬盘、CPU、内存、IO等）以及MQ的进程和端口，我们也可以通过请求url访问管理API监控其集群和队列的情况。在Java api 3.6.0以后，channel接口为我们提供了如下接口：

/**
 * Returns the number of messages in a queue ready to be delivered
 * to consumers. This method assumes the queue exists. If it doesn't,
 * an exception will be closed with an exception.
 * @param queue the name of the queue
 * @return the number of messages in ready state
 * @throws IOException Problem transmitting method.
 */
    long messageCount(String queue) throws IOException;

  /**
   * Returns the number of consumers on a queue.
   * This method assumes the queue exists. If it doesn't,
   * an exception will be closed with an exception.
   * @param queue the name of the queue
   * @return the number of consumers
   * @throws IOException Problem transmitting method.
   */
    long consumerCount(String queue) throws IOException;

messageCount：查询队列未消费的消息数，可以监控消息堆积的情况。 
consumerCount：队列的消费者个数，可以对消费者进行监控 
Java实例：

public class JavaAPIMonitor {

    private static String queue_name = "test_queue";

    public static void main(String[] args) throws Exception {
        ConnectionFactory factory = new ConnectionFactory();
        // amqp://userName:password@hostName:portNumber/virtualHost
        factory.setUri("amqp://test:test@10.1.199.169:5672/test");
        Connection conn = factory.newConnection();
        // System.out.println(conn.getChannelMax());
        Channel channel = conn.createChannel();
        // System.out.println(channel.getChannelNumber());
        System.out.println(channel.messageCount(queue_name));
        System.out.println(channel.consumerCount(queue_name));
        channel.close();
        conn.close();
    }
}
运行结果：
277782
3

除此之外，也可以通过连接的状态变化，进行监控，如：连接被阻塞（内存，CPU等不足）

ConnectionFactory factory = new ConnectionFactory();
        Connection connection = factory.newConnection();
        connection.addBlockedListener(new BlockedListener() {

            public void handleUnblocked() throws IOException {
                // 连接取消阻塞
            }
            public void handleBlocked(String reason) throws IOException {
                // 连接阻塞
            }
        });
        connection.addShutdownListener(new ShutdownListener() {
            public void shutdownCompleted(ShutdownSignalException cause) {
                //连接关闭
            }
        });

先关监控参考文章： 
1.RabbitMQ之管理与监控 
2.REST API监控RabbitMQ 
3.如何监控RabbitMQ 
4.使用AMQP模拟检测来确认RabbitMQ是否运行 
5.监控队列状态