In previous installments of this series I've concentrated on the -javaagent parameter for agent access. In this installment I'll introduce another way to access the inner workings of a JVM via an undercover agent; the -agentpath and -agentlib parameters.

As prevously presented, agent access was obtained via a Java class that was loaded early in the JVM startup sequence. This class had access to many areas of the JVM, but not all. By using an 'undercover' agent, access to much more fine-grained behavior can be obtained - but at a price.