What is Java factory class?

The factory design pattern says that define an interface ( A java interface or an abstract class) and let the subclasses decide which object to instantiate. The factory method in the interface lets a class defer the instantiation to one or more concrete subclasses.

What is factory object in Java?

In object-oriented programming (OOP), a factory is an object for creating other objects – formally a factory is a function or method that returns objects of a varying prototype or class from some method call, which is assumed to be “new”.

What is the use of factory class?

Factory Method Pattern allows the sub-classes to choose the type of objects to create. It promotes the loose-coupling by eliminating the need to bind application-specific classes into the code.

What is a factory class and how does it work?

A Factory Pattern or Factory Method Pattern says that just define an interface or abstract class for creating an object but let the subclasses decide which class to instantiate. In other words, subclasses are responsible to create the instance of the class.

How do you write a factory class in Java?

Design Pattern – Factory Pattern

  1. Implementation.
  2. Create an interface.
  3. Create concrete classes implementing the same interface.
  4. Create a Factory to generate object of concrete class based on given information.
  5. Use the Factory to get object of concrete class by passing an information such as type.
  6. Verify the output.

Why do we use Factory Pattern?

Factory design pattern is used to create objects or Class in Java and it provides loose coupling and high cohesion. Factory pattern encapsulate object creation logic which makes it easy to change it later when you change how object gets created or you can even introduce new object with just change in one class.

What is singleton factory in Java?

As the above UML diagram shows, a singleton class has a single instance defined and we access it by the getInstance () method. So a singleton factory that is responsible for creating objects makes use of the getInstance method to return the same object (which is there in the class) again and again.

Where is Factory Pattern used in Java?

The factory design pattern is used when we have a superclass with multiple sub-classes and based on input, we need to return one of the sub-class. This pattern takes out the responsibility of the instantiation of a class from the client program to the factory class.