make less exception

Took 4 minutes

include/KawaiiMQ/MessageQueueManager.h

@@ -37,15 +37,13 @@ namespace KawaiiMQ {
          * relate a queue to a topic
          * @param topic topic you want to relate
          * @param queue queue you want to relate
-         * @exception TopicException if the topic is already related to the queue
          */
         void relate(const Topic& topic, std::shared_ptr<Queue> queue);
 
         /**
          * unrelate a queue from a topic
          * @param topic topic you want to unrelate
          * @param queue queue you want to unrelate
-         * @exception TopicException if the topic is not related to the queue
          * @remark this function will wait until the queue is empty
          */
         void unrelate(const Topic& topic, std::shared_ptr<Queue> queue);
@@ -54,7 +52,7 @@ namespace KawaiiMQ {
          * get all queues related to the topic
          * @param topic given topic
          * @return all queues related to the topic
-         * @exception TopicException if the topic is not related to any queue
+         * @remark this function will return a empty vector when there is nothing related to this topic
          */
         std::vector<std::shared_ptr<Queue>> getAllRelatedQueue(const Topic& topic) const;
 

src/MessageQueueManager.cpp

@@ -15,18 +15,13 @@ namespace KawaiiMQ {
 
     void MessageQueueManager::relate(const Topic &topic, std::shared_ptr<Queue> queue) {
         std::lock_guard lock(mtx);
-        bool find = false;
         for (const auto& q : topic_map[topic]) {
             if (q->getName() == queue->getName()) {
-                find = true;
-                break;
+                return;
             }
         }
-        if (!find) {
-            topic_map[topic].push_back(queue);
-        } else {
-            throw QueueException("Attempted to relate duplicated queue in same topic: " + topic.getName());
-        }
+        topic_map[topic].push_back(queue);
+
     }
 
 
@@ -36,22 +31,15 @@ namespace KawaiiMQ {
         bool find = false;
         for (const auto& q : topic_map[topic]) {
             if (q->getName() == queue->getName()) {
-                find = true;
-                break;
+                auto &queues = topic_map[topic];
+                auto it = std::find_if(
+                        queues.begin(), queues.end(),
+                        [&queue](const std::shared_ptr<Queue> &q) {
+                            return queue->getName() == q->getName();
+                        });
+                queues.erase(it);
             }
         }
-        if (find) {
-            auto &queues = topic_map[topic];
-            auto it = std::find_if(
-                    queues.begin(), queues.end(),
-                    [&queue](const std::shared_ptr<Queue> &q) {
-                        return queue->getName() == q->getName();
-                    });
-            queues.erase(it);
-        }
-        else{
-            throw QueueException("Attempted to unrelate nonexistent queue from topic: " + topic.getName());
-        }
     }
 
     std::vector<std::shared_ptr<Queue>> MessageQueueManager::getAllRelatedQueue(const Topic& topic) const {
@@ -60,9 +48,9 @@ namespace KawaiiMQ {
             return topic_map.at(topic);
         }
         catch (std::out_of_range& e) {
-            throw TopicException("Topic " + topic.getName() + " is not related to any queue");
+            std::cerr << "Topic " + topic.getName() + " is not related to any queue";
+            return std::vector<std::shared_ptr<Queue>>();
         }
-
     }
 
     bool MessageQueueManager::isRelated(const Topic& topic, std::shared_ptr<Queue> queue) {