The Decorator pattern prefers composition over inheritance; therefore, it is an elegant alternative to the subclassing technique. With this, we mainly start from a base object and add additional features in a dynamic fashion.
For example, we can use this pattern to decorate a cake. The decoration process doesn't change the cake itself – it just adds some nuts, cream, fruit, and so on.
The following diagram illustrates what we will implement:
First, we create an interface called Cake:
public interface Cake { String decorate();}
Then, we implement this interface via BaseCake:
public class BaseCake implements ...
