Class ProcessorAbstract is an abstract class that
provides support for JavaMail processors. Concrete implementations are
required to implement the abstract method void process() to
process a JavaMail element.
Typically, processors are chained. A Store processor delegates to a Folder
processor that delegates to a Message processor.
ProcessorAbstract wraps an Account - see
org.apache.james.fetchmail.Account
- providing contextual information about the environment for the processor.