Home

Design patterns

1. Singleton pattern

- change visibility of constructor to private in order to prevent the creation of multiple instances.
- Declare a static instance in the class.
- Create static method that will return the instance.

2. Factory method pattern

- Create an interface that will be implemented by differents classes.
- Create differents classes to implement the interface.
- Create factory classe to get instance by passing the instance type.

3. Decorator pattern

This pattern allows you to add new functionality to an existing object without changing its structure.
- Create an interface that will be implemented by differents classes.
- Create differents classes to implement the interface.
- Create abstract class implement the interface in order to override methods .
- Create decorator class to extends this abstract class which wraps the original class and provides additional functionality keeping class methods signature intact.