This module explores the JavaBeans Development Kit (BDK) and the tools and resources it provides for Bean development.
After installing the BDK, you find out what the
BeanBox test container is and how it is used to customize and test Beans in a setting similar to application builder tools.
The JavaBeans Development Kit (BDK) and its associated tools are designed to facilitate the development, testing, and deployment of JavaBeans, which are reusable software components conforming to a set of conventions defined by the JavaBeans specification. The BDK provides a comprehensive environment and a set of utilities that streamline the process of creating, managing, and integrating JavaBeans into applications.
Key Features of the JavaBeans Development Kit:
- BeanBox Tool: The BeanBox is a central component of the BDK, serving as a visual testing and development environment where developers can place beans to test their properties, methods, and events. It allows for the interactive manipulation of bean properties and the observation of bean behavior in response to event triggers. This immediate feedback is crucial for fine-tuning bean functionalities and interfaces.
- Property Editors: Property editors are tools within the BDK that facilitate the customization of bean properties in a user-friendly manner. These editors provide graphical interfaces for setting and modifying the properties of beans, making it easier for developers and designers to configure beans without deep diving into the code. This is particularly useful for complex properties that can benefit from specialized editors, enhancing the usability and accessibility of bean customization.
- Customizer Support: The BDK enables beans to have associated customizers, specialized GUI components that provide a more sophisticated interface for configuring a bean's properties and its runtime behavior. Customizers allow for a high degree of control over the bean's configuration process, catering to complex beans that require intricate setup procedures beyond simple property editing.
- Introspection Tools: Introspection tools within the BDK assist in examining the features of a bean, such as its properties, events, and methods. These tools are essential for understanding the capabilities of a bean and for ensuring that it adheres to the JavaBeans conventions, such as proper naming patterns for getter and setter methods, event listener management, and so forth.
- Serialization Mechanisms: The BDK provides mechanisms to support the serialization and deserialization of beans, enabling their states to be saved and restored. This is crucial for developing beans that can maintain their state across different sessions, a key aspect of component reuse and deployment in larger applications.
- Documentation and Examples: Accompanying the BDK are comprehensive documentation and a set of example beans that serve as references and learning aids for developers. These resources are invaluable for understanding best practices in bean development, the nuances of the JavaBeans API, and the capabilities of the BDK tools.
- Compatibility and Integration Support: The tools within the BDK are designed to ensure that beans developed with it are compatible with a wide range of Java environments and can be easily integrated into various IDEs and application builders. This interoperability is crucial for the widespread adoption and use of JavaBeans in the development community.
By providing these tools and features, the JavaBeans Development Kit significantly simplifies the process of creating, testing, and deploying JavaBeans. It empowers developers to build modular, reusable components with well-defined interfaces, enhancing the modularity, maintainability, and scalability of Java applications.
After completing the module, I will show you the skills and knowledge necessary to:
- Customize a Bean at design time with the BeanBox
- Test a Bean at runtime with the BeanBox
In the next lesson, I will discuss how to install the BDK.
But what do beans provide that other classes do not? After all, beans are merely regular Java classes that follow some simple conventions
defined by the JavaBeans specification; beans extend no particular class, are in no particular package, and use no particular interface.
Although it is true that beans are merely Java classes that are written in a standard format, there are several advantages to their use. With beans in general, visual manipulation tools and other programs can automatically discover information about classes that follow this format and can create and manipulate the classes without the user having to explicitly write any code. In JSP in particular, use of JavaBeans components provides three advantages over scriptlets and JSP expressions that refer to normal Java classes.
- No Java syntax. By using beans, page authors can manipulate Java objects using only XML-compatible syntax: no parentheses, semicolons, or curly braces.
This promotes a stronger separation between the content and the presentation and is especially useful in large development teams that have separate Web and Java developers.
- Simpler object sharing. When you use the JSP bean constructs, you can much more easily share objects among multiple pages or between
requests than if you use the equivalent explicit Java code.
- Convenient correspondence between request parameters and object properties. The JSP bean constructs greatly simplify the process of reading request parameters, converting from strings, and putting the results inside objects.
As software developers, we are constantly being asked to build applications in less time and with less money.
In addition, these applications are expected to be better and faster than ever before. Object-oriented techniques and component software environments are in wide use now, in the hope that they can help us build applications more quickly.
Development tools like Microsoft's Visual Studio have made it easier to build applications faster by taking a building-block approach to software development. Such tools provide a visual programming model that allows you to include software components rapidly in your applications.
The JavaBeans architecture brings the component development model to Java, and that is the subject of this course.
But before we get started, I want to spend a little time describing the component model, and follow that with a general overview of JavaBeans.