非持久化模式下,Topic不会落地任何消息,消息入队即出队, 消费者如果想要保留离线后的消息需要告诉MQ实例,即注册过程, 代码上大概是这样的: connectionFactory = new ActiveMQConnectionFactory(username, password, brokerUrl); connection = connectionFactory.createConnection(); connection.setClientID(durableSubscribe.elem