1.paho.mqtt.java/Sample.java at master · eclipse/paho.mqtt.java · GitHub
https://github.com/eclipse/paho.mqtt.java/blob/master/org.eclipse.paho.sample.mqttv3app/src/main/java/org/eclipse/paho/sample/mqttv3app/Sample.java
客戶端收發同步的。客戶端的接收和發送消息是同步的,客戶端在收消息的時候,不能發送消息,反之亦反。
2.paho.mqtt.java/SampleAsyncCallBack.java at master · eclipse/paho.mqtt.java · GitHub
https://github.com/eclipse/paho.mqtt.java/blob/master/org.eclipse.paho.sample.mqttv3app/src/main/java/org/eclipse/paho/sample/mqttv3app/SampleAsyncCallBack.java
客戶端收發異步的。客戶端收發可以是同時的,兩條線程分別負責接收和發送。
3.paho.mqtt.java/SampleAsyncWait.java at master · eclipse/paho.mqtt.java · GitHub
https://github.com/eclipse/paho.mqtt.java/blob/master/org.eclipse.paho.sample.mqttv3app/src/main/java/org/eclipse/paho/sample/mqttv3app/SampleAsyncWait.java
這個也是收發異步的。跟第2個例子類似,但有區別,具體區別沒研究。