add comments

src/fr/api/Configuration.java

@@ -3,11 +3,43 @@ import java.util.Set;
 import java.util.Optional;
 
 public interface Configuration {
-    boolean isValid();
-    boolean isComplete();
+    /*
+    * @return true if there is no compatibility issue between PartType else false
+    */
+   boolean isValid();
+
+   /*
+    * @return true if the configuration is valid and done
+    */
+   boolean isComplete();
+
+    /*
+    * @return the list of the Part in the configuration
+    */
     public Set<Part> getSelectedParts(); 
+    
+    /*
+     * @return the Part that we chose earlier which has Category we choose
+     * it is optional
+     * @param catgeory : Category that we want to know about the PartType can be null
+     */
     public Optional<Part> getSelectionForCategory(Category category); 
+
+    /*
+     * Select a PartType to add to the configuration
+     * @param chosenPart : the PartType that we wish to add to the configuration
+     */
     void selectPart(PartType chosenPart);
+
+    /*
+     * DeSelect PartType has Catgerory catgoryToClear to delete from the configuration
+     * @param categoryToClear : the PartType has categoryToClear Category
+     * that we wish to delete from the configuration
+     */
     void unselectPartType(Category categoryToClear);
+    
+    /*
+     * Remove all PartType from configuation
+     */
     void clear();
 }