JavaBeans is a framework for
defining reusable modular software components. The JavaBeans
specification includes the following definition of a bean:
“a reusable software component that can be
manipulated visually in a builder tool.” As you can
see, this is a rather loose definition; beans can take a variety of
forms. The most common use of beans is for graphical user interface
components, such as components of the
javax.swing packages, which are documented in
Java Foundation Classes in a Nutshell and
Java Swing, both from O’Reilly.
Although all beans can be manipulated visually, this does not mean
every bean has its own visual representation. For example, the
javax.sql.RowSet class (documented in
Enterprise in a Nutshell) is a JavaBeans component that
represents the data resulting from a database query. There are no
limits on the simplicity or complexity of a JavaBeans component. The
simplest beans are typically basic graphical interface components,
such as a
java.awt.Button object. But even complex
systems, such as an embeddable spreadsheet application, can function
as individual beans.
The JavaBeans component model consists of the
java.beans.beancontext packages, and a number of important naming and API conventions to which conforming beans and bean-manipulation tools must adhere. These conventions are not part of the JavaBeans API itself but are in many ways more important to bean developers than the API itself. ...