Reflection and Interfaces

You might wonder what happens if you want to sort user-defined data structures, such as phone records or numeric data, based on your own criteria, such as a surname or a statistical property such as the mean value of a dataset. What happens when you want to sort different datasets that share a common behavior without having to implement sorting from scratch for each one of the different data types using multiple functions? Also, imagine that you want to write a utility that sorts uncommon data. For example, imagine that you want to sort a slice that holds various kinds of 3D shapes based on their volume. Can this be performed easily and in a way that makes sense?

The answer to all these questions and concerns is the use of interfaces. However, interfaces are not just about data manipulation and sorting. Interfaces are about expressing abstractions and identifying and defining behaviors that can be shared among different data types. Once you have implemented...