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[paho-dev] ?????? How to receive a "last will" message
Thxs Darren  , How to make "last will" trigger , I have tried a lot : disuse the network of subscriber , make a exception , run System.exit(1) or just terminate the subscriber .


------------------ ???????? ------------------
??????: "Darren Clark"<dclark@xxxxxxxxxxxxx>;
????????: 2013??8??24??(??????) ????5:48
??????: "General development discussions for paho project"<paho-dev@xxxxxxxxxxx>;
????: Re: [paho-dev] How to receive a "last will" message

Not sure if it's the same, probably depends on the client and where the exception happens, but  I was a bit confused at first about LWT. It is a message posted by the broker when it sees the client disconnect unexpectedly, not just any disconnect.

So if the exception handling on the client causes it to send a disconnect message to the broker then the LWT won't be sent. It will only be sent if the socket is dropped or some other scenario without a valid disconnect being sent.

-D

On Aug 24, 2013 2:14 AM, "??(Grey)??" <86267306@xxxxxx> wrote:

Hi,all:

         I am confused how to receive a LWT messsge. I have set a last will in a subscriber A , the last will topic is called "lastwill". and start subscriber B to listen the "lastwill" topic .

         When I make some exception in Subscriber A ,to make the Subscriber disconnect from broker , no message arrived in subscriber B. I noticed some document said Server will
      
         publish the last will message. I spent lots of time and found no answer , any help will be appreciated , thanks.

   mqttClient = new MqttClient("tcp://192.168.100.80:1883", MqttClient.generateClientId());
   

   MqttConnectOptions connectOptions = new  MqttConnectOptions();

   //set will
   connectOptions.setWill(mqttClient.getTopic("lastwill"), new String("I am offline").getBytes(), 1, false);
   mqttClient.connect(connectOptions);
   mqttClient.setCallback(new MqttCallback(){...}

 

 

 

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