Creational Design Pattern - Builder
Design Pattern
10 Articles
In this article, let's learn about Builder Design Pattern
in .NET.
Table of Contents
Introduction
Embarking on the journey of software design often involves constructing complex objects
with varying representations.
One tool in our design toolkit
that excels at this task is the Builder Pattern
.
As a creational pattern, it gracefully tackles the challenge of creating intricate objects by separating their construction from
their representation
.
In this exploration, we'll delve into the structure, use cases, advantages, and disadvantages of the
Builder Pattern
, accompanied by real-life examples.
Structure
At the core of the Builder Pattern
lies a structured framework that facilitates the
step-by-step construction of complex objects
. The fundamental components include:
Code Sample - Code Sample - Builder Pattern
In the above code, Builder Interface
is an abstract interface
defining the
creation of parts for the product object
. In our analogy, this is akin to a car builder
interface
, outlining methods like buildEngine
and
buildFrame
.
Concrete Builders
is an Implementations
of the builder
interface
, such as the BMW
and Mini
builders. These class
'es assemble the product and keep track of its representation, providing a method to
retrieve the final product.
Product
is the complex object
under construction, represented by the
car
in our example. It may include constituent parts like a frame or an engine.
Director
is the entity responsible for constructing the object
using
the builder interface
. In our analogy, think of a garage
orchestrating the
construction of cars.
Note: The builder can be implemented using interface
or
abstract class
.
Demo - Builder Pattern Demo
Let's try Builder
Demo, Click on the Build Mini Card and Build BMW Car to see the builder pattern in action.
The results will be displayed next to the buttons after building the respective cars.
Code Sample - Builder Pattern Demo
Mini Car :
BMW Car :
Use Cases
Algorithm Independence
- When you want the algorithm for creating a complex object independent of its parts and assembly process.Diverse Representations
- When the construction process should allow for different representations of the same object, like building distinct cars using the same construction process.- Other Real-world applications include generating documents, constructing database queries, designing game characters, and creating user interfaces or forms.
Advantages
Internal Representation Variability
- Enables variation in the internal representation of the product by providing a new builder.Isolation of Construction and Representation Code
- Enhances modularity by encapsulating the construction and representation details, following theSingle Responsibility Principle
.Fine-grained Construction Control
- Allows finer control over the construction process with step-by-step creation.
Disadvantages
While powerful, the Builder Pattern
introduces complexity to the codebase due to the creation of multiple classes. It's crucial to balance the benefits with the increased complexity.
Related Patterns
Abstract Factory
patternComposite
pattern
Summary
In the vast landscape of software design, the Builder Pattern
stands as a reliable guide for
constructing complex objects
with elegance and flexibility. Its ability to
separate construction from representation
empowers developers to navigate the intricacies of design,
providing a valuable tool for crafting robust and maintainable software.