In Unified Modeling Language (UML) class diagrams, an extends relationship (also called an inheritance or an is-a relationship) implies that a specialized (child) class is based on a general (parent) class.
In UML class diagrams, extends relationships apply only to container-managed persistence (CMP) entity beans. They do not apply to session or message-driven beans.
As the following figures illustrates, an extends relationship connector is displayed as a solid line with an unfilled arrowhead that points from the specialized (child) Java™ class or Enterprise JavaBeans™ (EJB) enterprise bean to the general (parent) Java class or EJB enterprise bean. You can also examine and design extends (inheritance) relationships between CMP entity beans.
Java source code | UML visualization |
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