Most common object models of distributed object systems have a limited
set of object-oriented features, lacking the advanced features of
`polymorphism' (an abstraction mechanism that represents a quality or
state of being able to assume different forms) and `concurrency' (the
ability to have more than one thread of execution in an object
simultaneously). The lack of support for advanced features is a
serious limitation because it restricts the development of new
components and limits reuse of existing of components that use these
advanced features. As a result, wrappers must be used that hide the
advanced features or components must be re-implemented using only the
features of the common object model.
In this dissertation, a new direction of research centered on a subset
of object-oriented languages, specifically statically typed languages,
is considered. One of the major drawbacks of existing distributed
object systems is that they cater to a broad domain of programming
languages including both object-oriented as well as non object-oriented
languages. Mapping an object model into a non object-oriented language
is a complex task and it does not appear natural to a native language
user.
The interoperable common object model (ICOM) proposed in this
dissertation is an attempt to elevate common object models (with the
advanced features of polymorphism and concurrency) closer to the object
models of statically typed object-oriented languages. Specific
features of the ICOM object model include: remote inheritance, method
overloading, parameterized types, and guard methods. The actor
model and reflection techniques are used to develop a uniform
implementation framework for the ICOM object model in C++ and
Modula-3. Prototype applications were implemented to demonstrate the
utility of the advanced features of the ICOM object model.
The main contributions of this dissertation are: design and
implementation of a powerful common object model, an architecture for
distributed compilation, and an implementation of a distributed object
model using the actor model.
