Like Article. Next Prototype Design Pattern. Recommended Articles. Article Contributed By :. Easy Normal Medium Hard Expert. Writing code in comment? Please use ide. Load Comments. What's New. Most popular in Design Pattern. More related articles in Design Pattern. A metal car and a paper manual, although related, are still very different things. Hence, we obtain the result of the construction from the builder which performed the job.
Say you have a constructor with ten optional parameters. Calling such a beast is very inconvenient; therefore, you overload the constructor and create several shorter versions with fewer parameters. These constructors still refer to the main one, passing some default values into any omitted parameters. Creating such a monster is only possible in languages that support method overloading, such as C or Java. The Builder pattern lets you build objects step by step, using only those steps that you really need.
Use the Builder pattern when you want your code to be able to create different representations of some product for example, stone and wooden houses. The Builder pattern can be applied when construction of various representations of the product involves similar steps that differ only in the details. The base builder interface defines all possible construction steps, and concrete builders implement these steps to construct particular representations of the product.
Meanwhile, the director class guides the order of construction. Use the Builder to construct Composite trees or other complex objects. The Builder pattern lets you construct products step-by-step. You could defer execution of some steps without breaking the final product. You can even call steps recursively, which comes in handy when you need to build an object tree. This prevents the client code from fetching an incomplete result.
Make sure that you can clearly define the common construction steps for building all available product representations. Create a concrete builder class for each of the product representations and implement their construction steps. Think about creating a director class. It may encapsulate various ways to construct a product using the same builder object. The client code creates both the builder and the director objects.
Before construction starts, the client must pass a builder object to the director. The director uses the builder object in all further construction. The construction result can be obtained directly from the director only if all products follow the same interface. Otherwise, the client should fetch the result from the builder.
Many designs start by using Factory Method less complicated and more customizable via subclasses and evolve toward Abstract Factory , Prototype , or Builder more flexible, but more complicated. Builder focuses on constructing complex objects step by step. Abstract Factory specializes in creating families of related objects.
Abstract Factory returns the product immediately, whereas Builder lets you run some additional construction steps before fetching the product. You can use Builder when creating complex Composite trees because you can program its construction steps to work recursively. You can combine Builder with Bridge : the director class plays the role of the abstraction, while different builders act as implementations.
Abstract Factories , Builders and Prototypes can all be implemented as Singletons. Hey, I have just reduced the price for all products. Check it out ». Intent Builder is a creational design pattern that lets you construct complex objects step by step.
Arnab Chakraborty. Manoj Kumar. Zach Miller. Sasha Miller. Design Patterns - Builder Pattern Advertisements.
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