### Question:
AWSIotMqttTopic { public AWSIotMqttNewMessageCallback getCallback() { return callback; } AWSIotMqttTopic(String topic, AWSIotMqttQos qos, AWSIotMqttNewMessageCallback callback); String getTopic(); void setTopic(String topic); AWSIotMqttQos getQos(); void setQos(AWSIotMqttQos qos); AWSIotMqttNewMessageCallback getCallback(); void setCallback(AWSIotMqttNewMessageCallback callback);  }### Answer:
@Test public void testGetCallback() throws Exception { assertEquals(callback1, topicModel.getCallback()); }