java如何使用JMS API将NACK从Solace侦听器发送到Solace队列？

Question

需要你的帮助才能找到解决方案。目前的实施细节：

SolConnectionFactory connectionFactory = SolJmsUtility.createConnectionFactory(); // for create connection factory using host , vpn,trust store,keystore with auth scheme AUTHENTICATION_SCHEME_CLIENT_CERTIFICATE
this.connection = connectionFactory.createConnection(); // connection creation
session = connection.createSession(false, Session.CLIENT_ACKNOWLEDGE); // session creation using client acknowledge

使用MessageListener监听队列

public class MyListener implements MessageListener 

    public void onMessage(Message message) // receive the message and process
    { 
        /* in this method validating the message (poison message) 
         * and publish to kafka, once receive the success message
         * from kafka acknowledge the message
         */
        message.acknowledge();
    }

问题：如果卡夫卡经纪人倒台了，如何重试？我们与内部慰藉小组进行了讨论

我们假设如果客户机没有调用message.acknowledge()Solace将进行重试，但Solace内部团队澄清，它正在使用窗口机制，因此如果后续消息被确认，那么之前的消息也将被确认并删除

他们的建议是将失败消息的NACK（否定确认）发回，然后Solace可以重试该消息。如何使用Java API发送NACK

Max_Un_Ack_Message和Max_Redeliver_Count的建议值是多少

Maven Dependence for Solace：

<dependency>
    <groupId>com.solacesystems</groupId>
    <artifactId>sol-jms</artifactId>
    <version>10.0.0</version>
</dependency>

Answer 1

如果您正在使用JMS API，并且希望触发重新交付，那么您有几个选项

你可以使用transacted session。当处理消息成功时，您确认消息并commit()确认javax.jms.Session。处理不成功时，在javax.jms.Session上调用rollback()

或者，您可以使用^{}。以下是JavaDoc所说的：

Stops message delivery in this session, and restarts message delivery with the oldest unacknowledged message.

All consumers deliver messages in a serial order. Acknowledging a received message automatically acknowledges all messages that have been delivered to the client.

Restarting a session causes it to take the following actions:

• Stop message delivery
• Mark all messages that might have been delivered but not acknowledged as "redelivered"
• Restart the delivery sequence including all unacknowledged messages that had been previously delivered. Redelivered messages do not have to be delivered in exactly their original delivery order.

当然，这是假设Solace JMS客户端实际上实现了这里指定的行为

Answer 2

根据讨论here，message.acknowledge()与窗口无关。由于在示例中使用的是异步解决方案，因此如果不调用stop()，传输窗口将关闭，消息将不会得到确认

message.acknowledge()仅用于确认消息已被接收和使用，其中消息已从Solace broker上的持久存储中删除。请注意，未确认的消息只会在下一个要连接的消费者上重新发送