Using output adapters to speak with different 
data sources

What characterizes an object-oriented system is its ability to treat data and behavior as closely related things. This proximity happens to mimic the way things are in the real world. Both animate and inanimate beings have attributes and can perform or be the target of some action. For people starting to learn object-oriented programming, we present examples such as a car, which has four wheels and can drive – wheels being the data and driving the behavior. Examples such as this express the fundamental principle that data and behavior should not be treated as separate things but should be united inside what we call objects.

This object idea has laid the ground for the development of vast and complex systems over the last decades. A good part of those systems is business applications running on enterprise environments. The object paradigm has conquered enterprise development because its high-level approach...