Java Design Patterns: A Hands-On Experience with Real-World Examples

© The Author(s), under exclusive license to APress Media, LLC, part of Springer Nature 2022

V. SarcarJava Design Patternshttps://doi.org/10.1007/978-1-4842-7971-7_26

26. Null Object Pattern

Vaskaran Sarcar¹  

(1)

Garia, Kolkata, India

 

This chapter covers the Null Object pattern.

Definition

It’s not a GoF design pattern. Here’s the definition from Wikipedia:

“In object-oriented computer programming, a null object is an object with no referenced value or with defined neutral (‘null’) behavior. The null object design pattern describes the uses of such objects and their behavior (or lack thereof). It was first published in the Pattern Languages of Program Design book series.”

Concept

The pattern can implement a “do-nothing” relationship, or it can provide ...