How to improve the builder pattern?

Question

Motivation

Recently I searched for a way to initialize a complex object without passing a lot of parameter to the constructor. I tried it with the builder pattern,

Answer 1

The Builder Pattern is generally used when you have a lot of optional parameters. If you find you need many required parameters, consider these options first:

• Your class might be doing too much. Double check that it doesn't violate Single Responsibility Principle. Ask yourself why you need a class with so many required instance variables.
• You constructor might be doing too much. The job of a constructor is to construct. (They didn't get very creative when they named it ;D ) Just like classes, methods have a Single Responsibility Principle. If your constructor is doing more than just field assignment, you need a good reason to justify that. You might find you need a Factory Method rather than a Builder.
• Your parameters might be doing too little. Ask yourself if your parameters can be grouped into a small struct (or struct-like object in the case of Java). Don't be afraid to make small classes. If you do find you need to make a struct or small class, don't forget to refactor out functionality that belongs in the struct rather than your larger class.