Correction étourderie (NPE), traces supplémentaires et logger.error à la place de printStackTrace

@@ -68,12 +68,11 @@ public class PostprocessingApplication {
                 sampleItemIds.add(itemId);
                 sampleUserIds.add(userId);
                 if (!sampleItemUserIds.containsKey(itemId)) {
-                    Set<Long> set = sampleItemUserIds.get(itemId);
-// NPE !!!
+                    Set<Long> set = new HashSet<>();
                     set.add(userId);
                     sampleItemUserIds.put(itemId, set);
                 } else {
-                    Set<Long> set = new HashSet<>();
+                    Set<Long> set = sampleItemUserIds.get(itemId);
                     set.add(userId);
                     sampleItemUserIds.put(itemId, set);
                 }
@@ -87,10 +86,10 @@ public class PostprocessingApplication {
             }
 
             logger.trace("Nombre de couples item-user dans l'échantillon {}", sampleCoupleCount);
+            logger.trace("Nombre de couples item-user recommandables {}", sampleItemIds.size() * sampleUserIds.size() - sampleCoupleCount);
 
         } catch (IOException e) {
-            //fixme use logger instead of e.printStackTrace() !!!
-            e.printStackTrace();
+            logger.error("analyzeSample IOException : {}", e.getStackTrace());
         }
 
     }
@@ -112,8 +111,6 @@ public class PostprocessingApplication {
 
     void loadParametersProperties() {
 
-        //fixme use logger instead of e.printStackTrace() !!!
-
         Properties properties = new Properties();
         InputStream in = null;
         try {
@@ -122,9 +119,9 @@ public class PostprocessingApplication {
             properties.load(in);
             in.close();
         } catch (FileNotFoundException e) {
-            e.printStackTrace();
+            logger.error("analyzeSample FileNotFoundException : {}", e.getStackTrace());
         } catch (IOException e) {
-            e.printStackTrace();
+            logger.error("analyzeSample IOException : {}", e.getStackTrace());
         }
 
         this.properties = properties;