What are the advantages and features of using composition in programming?

Composition is a principle where an object is created from other objects, using their functionality instead of inheritance. In Android and general programming, composition has several advantages:

• Flexibility: the behavior of an object can be changed at runtime by replacing components.
• Reusability: components can be used in different objects.
• Avoidance of inheritance issues: composition does not lead to rigid class hierarchies and problems with multiple inheritance.
• Simplified testing: individual components are easier to test separately.

For example, in Android, composition is often used to add functionality to an Activity or View through delegates or helper classes, instead of creating complex inheritance hierarchies.