Chapter 2. Object Persistence Fundamentals

“We are made to persist. That's how we find out who we are.”

—Tobias Wolff, In Pharaoh's Army

This chapter looks at the challenges that a persistence solution must address. A closer look is taken at object-relational mapping solutions in particular. The effort of a “from-scratch” implementation of such a framework is then outlined.

It is perfectly possible to use JDO without indulging in the underlying issues that a JDO implementation solves for you. However, it may still be helpful to at least be aware of them. Read the rest of this chapter to get an idea of the questions that you would generally trust the JDO implementation to have solved for you.

Alternatively, you can skip this chapter at this point and plunge straight into the usage of JDO in the following chapters. Be sure to come back and read this chapter, though; it's full of great information.