What is the advantage of the Builder design pattern compared to a regular constructor?

The advantages are as follows:

• Readability and clarity of code: When there are many parameters, the constructor becomes bulky and hard to read. Builder allows assigning values to parameters by their names, making the code more understandable.

// Without Builder
ComplexObject obj = new ComplexObject(value1, value2, null, true, null, value6);

// With Builder
ComplexObject obj = new ComplexObject.Builder()
    .setValue1(value1)
    .setValue2(value2)
    .setFlag(true)
    .setValue6(value6)
    .build();

• Support for optional parameters: Not all parameters are always needed. Builder makes it easy to create objects with different combinations of optional parameters, avoiding a large number of overloaded constructors.
• Immutability (optional): Builder is often used to create immutable objects, which increases safety and simplifies multithreaded programming. The object is fully configured in one step.
• Control over the order of setting parameters: Although not obvious, Builder can control the order in which parameters are set if necessary (for example, for dependent parameters).
• Improved testability: Individual setter methods in Builder are easier to test compared to a single large constructor.