Handle invalid unit data in menu.txt

src/main/java/seedu/cafectrl/storage/Decoder.java

@@ -68,19 +68,26 @@ private static void decodeDishString(String dishString, ArrayList<Dish> menuDish
      * @param ingredientsStringArray An array of strings containing encoded ingredient data.
      * @return An ArrayList of Ingredient objects containing the decoded ingredient information.
      */
-    private static ArrayList<Ingredient> decodeIngredientData(String[] ingredientsStringArray) {
+    private static ArrayList<Ingredient> decodeIngredientData(String[] ingredientsStringArray) throws Exception{
         ArrayList<Ingredient> ingredientList = new ArrayList<>();
         for(String ingredientString : ingredientsStringArray) {
             logger.info("Ingredient to decode: " + ingredientString);
             String[] array = ingredientString.split(INGREDIENT_DIVIDER);
             String name = array[0].trim();
             int qty = Integer.parseInt(array[1].trim());
             String unit = array[2].trim();
+            checkUnitValidity(unit);
             ingredientList.add(new Ingredient(name, qty, unit));
         }
         return ingredientList;
     }
 
+    private static void checkUnitValidity(String unit) throws Exception {
+        if (!Parser.isValidUnit(unit) || Parser.isEmptyUnit(unit)) {
+            throw new Exception();
+        }
+    }
+
     //@@author ziyi105
     /**
      * Decodes raw string from pantry stock data file and create ingredient object from the data