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Lesson 3 JavaBeans Development Kit Components
ObjectiveWhat does the BDK consist of?

JavaBeans Development Kit Components

Familiarize yourself with the contents of the BDK.

The BDK contains both information and tools to aid you as you design and develop JavaBeans components.
Select a part of the BDK to learn more about it:
  1. The BeanBox test container
  2. Example Beans and source code
  3. API source code
  4. JavaBeans tutorial

In the next lesson I will discuss how to run the BeanBox test container.
In addition, I will discuss the different parts of its user interface.

Storing customized components

When a human has customized the behaviour of a set of components, the application builder should use the persistence mechanisms described in Section 5 to store away the state of the components. When the application is run, this pickled state should be read back in to initialize the components.



Discovery and Registration

Class and interface discovery is the mechanism used to locate a component at run-time and to determine its supported interfaces so that these interfaces can be used by others. The component model must also provide a registration process for a component to make itself and its interfaces known. The component, along with its supported interfaces, can then be discovered at run-time. Dynamic (or late) binding allows components and applications to be developed independently. The dependency is limited to the "contract" between each component and the applications that use it; this contract is defined by interfaces that the component supports. An application does not have to include a component during the development process in order to use it at run-time; it only needs to know what the component is capable of doing. Dynamic discovery also allows developers to update components without having to rebuild the applications that use them.
This discovery process can also be used in a design-time environment. In this case, a development tool may be able to locate a component and make it available for use by the designer. This is important for visual programming environments, which are discussed later.