The Builder Design Pattern allows creating complex objects step-by-step in a consistent way. It solves issues with Factory patterns by using a builder class with setters for optional parameters that returns the builder, allowing chaining, rather than requiring all parameters up front. The final object is then built by calling a build method on the fully configured builder.

1. Builder Design Pattern
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2. What ?
• It Is a object creation software design pattern
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3. Why?
• Introduced to solve problems with Factory and Abstract-Factory
patterns.
• if object creation is with ‘n’ number of arguments, then It is difficult maintain
order of arguments.
• Some times few arguments are optional, but need to send as null.
• Creation of complex object creation will fall in Factory classes.
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4. Why?
• Issues with Factory patterns can be solved by creating constructors
with large number of required arguments and by having setter
methods for optional parameters.
• Problem with this is, object state would be not consistent until and unless all
optional parameters are set explicitly.
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5. How?
• Builder pattern solves the issue in the following way
• Create static nested builder class by copying all the argument from outer
class.
• Create public constructor with required attributes and setter methods for
optional parameters.( Setter methods should return the builder class).
• Provide build method which returns desired class object, for this need to
create private constructor in desired class.
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6. Example
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