Methodology Section Index
What is session facade?
Session facade is one design pattern that is often used while developing enterprise applications.
It is implemented as a higher level component (i.e.: Session EJB), and it contains all the iteract...more
Where can I find a glossary of UML-related terms?
Kendall Scott has written several UML-related books and maintains a dictionary of over 600 related terms for them.
What is the Reactor pattern?
The new book "Pattern-oriented Software Architecture Volume 2" ISBN 0471606952 has a chapter on the Reactor pattern. It falls under the general category of "Event Handling Patterns...more
How do you write a Thread-Safe Singleton?
I have written plenty of non-thread-safe Singletons but it wasn't until recently when I tracked it down that I realized that thread-safety could be a big problem.
The problem is that in the typic...more
How would you use UML to model multiple relationships between the same two classes?
How would you use UML to model multiple relationships between the same two classes? For example, an employee has both a permanent address and a temporary address.
What is an association class?
An association class is used to model an
association as a class. Association classes often
occur in many-to-one and many-to-many associations
where the association itself has attributes.
As an e...more
What is the difference between composition and aggregation?
Both aggregation and composition are
special kinds of associations. Aggregation is
used to represent ownership or a whole/part
relationship, and composition is used to
represent an even stronger ...more
What tools are good for generating UML diagrams from Java class definitions?
There are a number of tools for working
with UML, and most of them support both Java code
generation from UML diagrams and reverse
engineering into UML from Java source code or
Java byte code. Se...more
What are the plans to represent a Java throws signature element in a UML method signature and how should I represent a Java throws signature element in a UML method signature?
As far as official plans, you'll have to get word directly from someone on the UML 2.0 committee at the OMG - of which I am not (said with a sign of relief :-)
Looking at Grady's book (UML User's...more
What is a stereotype? Where can this be used? What is a stereotype? Where can this be used?
I think you are referring to a concept in UML modeling and not something associated strictly with XML.
In the Unified Modeling Language (UML) a stereotype is one way to extend the core semantics o...more
Is it correct from a design point of view to make an object both an Observer and Observable at the same time?
Yes, and this can be the preferred pattern in some cases.For example, suppose you were writing a supply chain management system for a retail chain. Each store object in your system generates item...more
Can I use class diagrams to model the logical database design? E.g., can I create a class diagram where each class represents a table in a database and then show the relationships between them along with their attributes and operations (such as stored procedures)?
I got this answer from Eric Naiburg, who is an expert in this area of UML application, and he said:
Yes you can use the class diagram to model the logical data model and it in fact is very well s...more
What is the difference between an API and a framework?
Here is a less formal definition:
A framework is a set of classes which handles the flow necessary to perform a complex task, but which requires plug-in classes specific to your application (datab...more
If I'm not object-oriented savvy, from what books can I learn UML?
Check out the UML Explained book from Kendall Scott. It provides a non-technical introduction to UML. See DevX for a review.
more
How do we express the relationships between EJB Entity Beans in UML?
I wish I had a quick answer for you, but the real answer lie in the activities of the JSR 26 committee. This group is currently working on a formal extension (profile) to the UML for modeling EJB...more