Null Object Design Pattern

Provides a default object.

Advantages

• You don't need to validate if the always is null before using it every single time
• Avoid null references if you forget to validate it before using
• It speeds up the code, by eliminating unnecessary if checks

Disadvantages

• Can waste memory if there are a lot of null objects
• The “do-nothing” behavior may not be well defined
• Sometimes a null object must be replaced by a real object