我目前正在爲持久訂閱編寫一個messenger服務(它可能最終會變得不耐用,我們仍在討論這一點),並且正在尋找一些關於如何處理我們的服務器由於某種原因暫時關閉的場景,我們需要自動重新訂閱該主題。下面是它如何連接的示例代碼:設置JMS連接以便自動重新連接的理想方法
public void DurableChatter(String broker, String username, String password)
{
javax.jms.MessageProducer publisher = null;
javax.jms.MessageConsumer subscriber = null;
javax.jms.Topic topic = null;
//Create a connection:
try{
javax.jms.ConnectionFactory factory;
factory = (new progress.message.jclient.ConnectionFactory (broker));
connection = factory.createConnection (username, password);
//Durable Subscriptions are indexed by username, clientID and subscription name
//It is a good proactice to set the clientID:
connection.setClientID(CLIENT_ID);
pubSession = connection.createSession(false,javax.jms.Session.AUTO_ACKNOWLEDGE);
subSession = connection.createSession(false,javax.jms.Session.AUTO_ACKNOWLEDGE);
}
catch (javax.jms.JMSException jmse){
System.err.println ("Error: Cannot connect to Broker - " + broker);
jmse.printStackTrace();
System.exit(1);
}
//Create Publisher and Durable Subscriber:
try{
topic = pubSession.createTopic(APP_TOPIC);
subscriber = subSession.createDurableSubscriber(topic, "SampleSubscription");
subscriber.setMessageListener(this);
publisher = pubSession.createProducer(topic);
connection.start();
}
catch (javax.jms.JMSException jmse){
System.out.println("Error: connection not started.");
jmse.printStackTrace();
System.exit(1);
}
//Wait for user input
try
{
System.out.println("Enter text to send as message and press enter.");
java.io.BufferedReader stdin =
new java.io.BufferedReader(new java.io.InputStreamReader(System.in));
while (true)
{
String s = stdin.readLine();
if(s == null){
exit();
}
else if (s.length()>0)
{
try
{
javax.jms.TextMessage msg = pubSession.createTextMessage();
msg.setText(username + ": " + s);
//Publish the message persistantly:
publisher.send(
msg, //message
javax.jms.DeliveryMode.PERSISTENT, //publish persistantly
javax.jms.Message.DEFAULT_PRIORITY,//priority
MESSAGE_LIFESPAN); //Time to Live
}
catch (javax.jms.JMSException jmse){
System.err.println("Error publishing message:" + jmse.getMessage());
}
}
}
}
catch (java.io.IOException ioe)
{
ioe.printStackTrace();
}
}
如果這就是你要求的,它不一定是瞬間的。無論如何,這可以通過try/catch塊來完成嗎? – Icebreaker 2012-07-20 17:16:14
僅當底層連接斷開時引發某種異常。我不能不告訴你。 – radai 2012-07-22 20:03:32