public interface BeanInfo
A bean implementor who wishes to provide explicit information about their bean may provide a BeanInfo class that implements this BeanInfo interface and provides explicit information about the methods, properties, events, etc, of their bean.
A bean implementor doesn't need to provide a complete set of explicit information. You can pick and choose which information you want to provide and the rest will be obtained by automatic analysis using low-level reflection of the bean classes' methods and applying standard design patterns.
You get the opportunity to provide lots and lots of different information as part of the various XyZDescriptor classes. But don't panic, you only really need to provide the minimal core information required by the various constructors.
See also the SimpleBeanInfo class which provides a convenient "noop" base class for BeanInfo classes, which you can override for those specific places where you want to return explicit info.
To learn about all the behaviour of a bean see the Introspector class.