What Is Factory Design Pattern9 min read

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The factory design pattern is a software engineering pattern that facilitates the creation of objects without specifying the exact class to create. The pattern defines a generic Factory interface that contains a create() method. Concrete factories are implemented to create objects of specific types. The pattern allows the creation of objects without relying on hard-coded class names. This pattern also allows the creation of subclasses without changing the factory.

The factory design pattern is useful when:

– You need to create objects of specific types but don’t know the class names.

– You need to create a subclass of a specific class but don’t know the class name.

– You want to create objects without specifying the exact class to create.

The factory design pattern has four components:

1. Factory interface – Defines a create() method that returns an object of a specific type.

2. Concrete factories – Implement the Factory interface and create objects of specific types.

3. Client – Uses the Factory interface to create objects.

4. Factory registry – Stores a list of factories and the type of object each factory creates.

The factory design pattern is implemented using Java. The following example shows how to create a factory interface and two concrete factories.

Factory interface

public interface Factory {

public Object create();

}

Concrete factories

public class SquareFactory implements Factory {

public Object create() {

return new Square();

}

}

public class CircleFactory implements Factory {

public Object create() {

return new Circle();

}

}

Client

public class Client {

public static void main(String[] args) {

Factory squareFactory = new SquareFactory();

Factory circleFactory = new CircleFactory();

Square square = squareFactory.create();

Circle circle = circleFactory.create();

}

}

Factory registry

Factory registry

public class FactoryRegistry {

private Factory[] factories;

private String type;

public FactoryRegistry() {

factories = new Factory[2];

type = “square”;

factory1 = factories[0];

factory2 = factories[1];

}

public Factory getFactory(String type) {

return factories[type];

}

}

The factory design pattern is useful for creating objects without knowing the class name. The pattern also allows the creation of subclasses without changing the factory.

What is meant by factory design pattern?

Factory design pattern is a creational design pattern that creates objects without specifying the exact class of object to be created. Factory design pattern uses a template method to create objects. The template method defines the steps needed to create a particular object, but leaves the actual work of creating the object to subclasses. Factory design pattern is also known as Abstract Factory Pattern.

What is the purpose of factory design pattern?

The factory design pattern is one of the most commonly used patterns in object-oriented programming. It is a creational pattern that allows you to create objects without specifying the exact class of object to be created. This pattern is useful when you want to create a number of objects of the same type, but you do not know in advance what type of object to create.

The factory pattern relies on a factory object that is responsible for creating the objects you want to create. The factory object contains a method that creates objects of a particular type. You can then call the factory object’s method to create an object of the desired type.

The factory pattern is often used when you need to create objects that belong to a specific interface, but you do not know what class to create the objects from. For example, imagine that you need to create a number of objects that all implement the same interface. You could create a factory object that contains a method that creates objects that implement the desired interface.

The factory pattern can also be used to create objects that are based on a template. For example, you could create a factory object that contains a method that creates objects that are based on a specific template.

What is factory design pattern with real time example?

Factory design pattern is one of the creational patterns in software engineering. It is used to create objects without specifying the exact class of the object. Factory design pattern is implemented by creating a separate factory class which is responsible for creating objects.

Factory design pattern is implemented by creating a separate factory class which is responsible for creating objects. The factory class contains a method which creates an object of a specific type. The client class calls the factory method to create an object. The factory class contains a list of classes which it can create. The client class can then call the factory method to create an object of the desired class.

Factory design pattern is often used when the client does not know the exact class of the object that it needs. For example, the client may need an object of type A but the factory may only have objects of type B. In this case, the factory can create an object of type A by using a class that is specific to type A.

Factory design pattern is often used in GUI applications. For example, a factory class may be used to create windows, menus, and other GUI components.

What is the use of factory design pattern in Java?

The Factory Method pattern is one of the most commonly used patterns in Java. It is a creational pattern that allows you to create objects without specifying the class of the object. This pattern relies on the use of a factory method, which is a method that returns an object of a specific type.

The Factory Method pattern can be used to create objects of different types, depending on the needs of your application. For example, you might use the Factory Method pattern to create different types of objects depending on the user’s role. You could also use the Factory Method pattern to create objects that are specific to the current environment.

The Factory Method pattern is a good choice for creating objects because it allows you to decouple the object creation process from the object’s actual implementation. This can be useful in situations where you need to create multiple objects of the same type, but you don’t want to create the objects in the same way.

The Factory Method pattern can also be used to create mock objects. Mock objects are objects that are used for testing purposes. They allow you to test your code without actually invoking the code’s dependencies.

The Factory Method pattern is a good choice for creating mock objects because it allows you to create mock objects without knowing the class of the object that you want to create. This can be useful in situations where you need to test code that relies on a specific type of object.

What is the factory method patterns explain with examples?

What is the factory method patterns?

The factory method pattern is a creational design pattern in software engineering. It is a pattern for creating objects, often used when the object’s constructor is long or complex. The factory method pattern uses a factory class to create objects, rather than having the constructor of the class itself create the objects.

The factory method pattern can be used to create objects in two ways. The first way is to create a subclass of the factory class, and then override the factory method to create the desired object. The second way is to create an instance of the factory class, and then call the factory method to create the desired object.

The factory method pattern has the following benefits:

The factory method pattern makes it possible to create objects without knowing the exact class of the object that will be created.

The factory method pattern makes it possible to create objects without knowing the exact constructor arguments that will be used to create the object.

The factory method pattern makes it possible to create objects without knowing the exact order of the constructor arguments.

The factory method pattern makes it possible to create objects without knowing the name of the constructor.

The factory method pattern is often used when the constructor of a class is long or complex.

The factory method pattern is often used when the constructor of a class requires a lot of arguments.

The factory method pattern is often used when the order of the constructor arguments is important.

The factory method pattern is often used when the name of the constructor is not known.

The following example shows how to use the factory method pattern to create a Date object. The Date constructor requires three arguments: the year, the month, and the day. The factory method in the Date class creates a Date object by calling the Date constructor with the values for the year, the month, and the day.

The following example shows how to use the factory method pattern to create a Point object. The Point constructor requires two arguments: the x-coordinate and the y-coordinate. The factory method in the Point class creates a Point object by calling the Point constructor with the values for the x-coordinate and the y-coordinate.

The following example shows how to use the factory method pattern to create a Rectangle object. The Rectangle constructor requires four arguments: the length, the width, the height, and the angle. The factory method in the Rectangle class creates a Rectangle object by calling the Rectangle constructor with the values for the length, the width, the height, and the angle.

The following example shows how to use the factory method pattern to create a Triangle object. The Triangle constructor requires three arguments: the base, the height, and the angle. The factory method in the Triangle class creates a Triangle object by calling the Triangle constructor with the values for the base, the height, and the angle.

What are the types of factory pattern?

There are three types of factory pattern:

1. Abstract factory pattern: This type of factory pattern is used to create families of related objects.

2. Prototype pattern: This type of factory pattern is used to create a new object by cloning an existing object.

3. Builder pattern: This type of factory pattern is used to create complex objects by assembling them from simple parts.

What is factory used for?

Factory can be used for a variety of purposes. The most common use of factory is to produce goods or products. Factories can be used to produce a wide range of products, from cars to clothes to electronic devices. Factories can be very large and complex, with multiple production lines and workers.

Another common use of factory is to produce energy. Factories can be used to produce electricity, either through burning coal or other fuels or through renewable sources like solar or wind power. Factories can also be used to produce ethanol or other biofuels.

Factory can also be used for research and development. Many large companies have their own research and development divisions, and these divisions often operate out of factories. Factory can also be used to produce medicines and other pharmaceutical products.

Factory is a very versatile word, and it can be used for a variety of purposes. The most common use of factory is to produce goods or products, but factories can also be used to produce energy or to conduct research and development.