Beans are designed above all to be simple. You need only add a
minimal amount of code to an existing class definition to turn a class
into a JavaBean.
In the simplest case, you need only add a pair of methods to an
existing class definition in order to make a Bean. This can be done
either by modifying the source for an existing class, or by extending
the behavior of an existing class by subclassing it.
On first impression, there appears to be no difference between a
JavaBean and a traditional Java AWT component object. This appearance
is intentional. While there are minor differences, such as the fact
that Beans need not be visible components, Java you need only follow a
few simple rules to make Beans out of existing classes.