This class represents a reference to an object that is found outside of
the naming/directory system.
Reference provides a way of recording address information about
objects which themselves are not directly bound to the naming/directory system.
A Reference consists of an ordered list of addresses and class information
about the object being referenced.
Each address in the list identifies a communications endpoint
for the same conceptual object. The "communications endpoint"
is information that indicates how to contact the object. It could
be, for example, a network address, a location in memory on the
local machine, another process on the same machine, etc.
The order of the addresses in the list may be of significance
to object factories that interpret the reference.
Multiple addresses may arise for
various reasons, such as replication or the object offering interfaces
over more than one communication mechanism. The addresses are indexed
starting with zero.
A Reference also contains information to assist in creating an instance
of the object to which this Reference refers. It contains the class name
of that object, and the class name and location of the factory to be used
to create the object.
The class factory location is a space-separated list of URLs representing
the class path used to load the factory. When the factory class (or
any class or resource upon which it depends) needs to be loaded,
each URL is used (in order) to attempt to load the class.
A Reference instance is not synchronized against concurrent access by multiple
threads. Threads that need to access a single Reference concurrently should
synchronize amongst themselves and provide the necessary locking.