What is factory design pattern in JS?
The factory pattern is a type of Object Oriented pattern which follows the DRY methodology. As the name suggests, object instances are created by using a factory to make the required object for us. … Dynamic object creation: It can be used in cases where the type of the object is decided at runtime.
What type of design pattern is factory?
Factory method is a creational design pattern, i.e., related to object creation. In Factory pattern, we create objects without exposing the creation logic to the client and the client uses the same common interface to create a new type of object.
Why is factory design pattern used?
The Factory Method pattern is generally used in the following situations: A class cannot anticipate the type of objects it needs to create beforehand. A class requires its subclasses to specify the objects it creates. You want to localize the logic to instantiate a complex object.
What is constructor pattern?
Object constructors are used to create specific types of objects—both preparing the object for use and accepting arguments a constructor can use to set the values of member properties and methods when the object is first created (Figure 9-1). …
What is a factory function C++?
A factory method is a static method of a class that returns an object of that class’ type. But unlike a constructor, the actual object it returns might be an instance of a subclass. Another advantage of a factory method is that it can return existing instances multiple times.
Which are the three types of factory method?
There are 3 types of factory design pattern.
- Simple factory.
- Factory method.
- Abstract factory.
What problem does factory pattern solve?
Factory method is a creational design pattern which solves the problem of creating product objects without specifying their concrete classes. Factory Method defines a method, which should be used for creating objects instead of direct constructor call ( new operator).
Why is factory pattern bad?
That’s just a bad habit. The Factory Method is a design pattern that relies on inheritance. If you make it static , you can no longer extend it in subclasses, which defeats the purpose of the pattern. When a static creation method returns new objects it becomes an alternative constructor.
What are the different design patterns?
There are five well-known design patterns possible to implement in a wide scope of programming languages:
- Abstract Factory Pattern.
- Builder Pattern.
- Factory Method Pattern.
- Prototype Pattern.
- Singleton Pattern.