订阅关系不一致

原因描述

在不同的JVM中启动了多个Consumer，并且给相同的Group ID配置了不同的Topic，或者是相同的Topic但Tag不同，最终导致订阅关系不一致，消息不符合预期。

错误代码示例

• 错误示例一：同一个Group ID（GID-MQ-FAQ）订阅的Topic不同（分别是MQ-FAQ-TOPIC-1、MQ-FAQ-TOPIC-2）。

  JVM-1上的代码：

  
      Properties properties = new Properties();
      properties.put(PropertyKeyConst.GROUP_ID, "GID-MQ-FAQ");
      Consumer consumer = ONSFactory.createConsumer(properties);
      consumer.subscribe("MQ-FAQ-TOPIC-1", "NM-MQ-FAQ", new MessageListener() {
          public Action consume(Message message, ConsumeContext context) {
              System.out.println("Receive: " + message);
              return Action.CommitMessage;
          }
      });
      consumer.start();            

  JVM-2上的代码

  
  
  
       Properties properties = new Properties();
      properties.put(PropertyKeyConst.GROUP_ID, "GID-MQ-FAQ");
      Consumer consumer = ONSFactory.createConsumer(properties);
      consumer.subscribe("MQ-FAQ-TOPIC-2", "NM-MQ-FAQ", new MessageListener() {
          public Action consume(Message message, ConsumeContext context) {
              System.out.println("Receive: " + message);
              return Action.CommitMessage;
          }
      });
  
      consumer.start();

• 错误示例二：同一Group ID（GID-MQ-FAQ）订阅的Topic相同，但Tag不同（分别NM-MQ-FAQ-1、NM-MQ-FAQ-2）。

  JVM-1上的代码：

  
  
  
      Properties properties = new Properties();
      properties.put(PropertyKeyConst.GROUP_ID, "GID-MQ-FAQ");
      Consumer consumer = ONSFactory.createConsumer(properties);
      consumer.subscribe("MQ-FAQ-TOPIC-1", "NM-MQ-FAQ-1", new MessageListener() {
          public Action consume(Message message, ConsumeContext context) {
              System.out.println("Receive: " + message);
              return Action.CommitMessage;
          }
      });
      consumer.start();
                      

  JVM-2上的代码

  
  
  
       Properties properties = new Properties();
      properties.put(PropertyKeyConst.GROUP_ID, "GID-MQ-FAQ");
      Consumer consumer = ONSFactory.createConsumer(properties);
      consumer.subscribe("MQ-FAQ-TOPIC-1", "NM-MQ-FAQ-2", new MessageListener() {
          public Action consume(Message message, ConsumeContext context) {
              System.out.println("Receive: " + message);
              return Action.CommitMessage;
          }
      });
  
      consumer.start();

建议解决方案

请确保在不同JVM中使用相同的Group ID启动多个Consumer时，配置的Topic和Tag是一致的。