In this chapter, we explain how to instrument (or "aspectize") the POJOs via JBossAop. There are two steps needed by JBossAop: 1) POJO declaration, 2) instrumentation. But depends on the JDK and instrumentation mode that you are using, you may not need to pre-process your POJO at all. That is, if you use JDK5.0 and load-time mode, then all you need to do is annotation your POJO (or declare it in a xml file). This makes your PojoCache programming nearly transparent.

For the first step, since we are using the dynamic Aop feature, a POJO is only required to be declared "prepare". Basically, there are two ways to do this: either via explicit xml or annotation (new since release 1.2.3.)

As for the second step, either we can ask JBossAop to do load-time (through a special class loader, so-called loadtime mode) or compile-time instrumentation (use of an aopc pre-compiler, so-called precompiled mode)