The Builder pattern is used in situations where the creation of a complex object is required, and the creation is generally achieved through a number of steps until the final product is ready.
A classic example is that of a car as a final product, which is created in steps by adding the engine, chassis, body, tires, and so on. The main client asks for the product and receives the final product with all the creation steps hidden from it. This is achieved via a Director class.
The basic builder pattern involves a Director, Builder, and Product class, as shown in the following diagram:
Let's look at an example in the code. We ...
