Null Object Design Pattern: → Replace “null” check. → Traditional method: null check for every value which has some limitations in code flow. If we follow “null object design pattern” then we can over that hurdle. → Default behaviour for objects which has “null” or “nothing. → Null object class is the default implementation. → It would very useful if we want some special flow for something which has nothing or null value. → Example: Spam classification. ------------------------------