Java Beans Questions et reponses d'entretien
Question 41. What is a Bean? Why is not a Bean an Applet?
JavaBeans components, or Beans, are reusable software components that can be manipulated visually in a builder tool. Beans can be combined to create traditional applications, or their smaller web-oriented brethren, applets. In addition, applets can be designed to work as reusable Beans.
Individual Beans will function quite differently, but typical unifying features that distinguish a Bean are:
► Introspection: enables a builder tool to analyze how a Bean works
► Customization: enables a developer to use an app builder tool to customize the appearance and behavior of a Bean
► Events: enables Beans to communicate and connect together
► Properties: enable developers to customize and program with Beans
► Persistence: enables developers to customize Beans in an app builder, and then retrieve those Beans, with customized features intact, for future use.
Question 42. Why are component architectures useful?
Developers are turning to creating components rather than monolithic applications to free themselves from slow, expensive application development, and to build up a portable, reusable code base. This enables developers to quickly attack new market opportunities, new joint development opportunities, and new ways to sell smaller packages of software.
Question 43. Is JavaBeans a complete component architecture?
JavaBeans is a complete component model. It supports the standard component architecture features of properties, events, methods, and persistence. In addition, JavaBeans provides support for introspection (to allow automatic analysis of a JavaBeanscomponent) and customization (to make it easy to configure a JavaBeans component).
Question 44. Why a component architecture for the Java platform?
JavaBeans brings the extraordinary power of the Java platform to component development, offering the ideal environment for a developer who wants to extend the concept of reusable component development beyond one platform and one architecture to embrace every platform and every architecture in the industry.
Question 45. What kind of industry support exists for JavaBeans?
A coalition of industry leaders in component development worked with JavaSoft to create the JavaBeans specification, which was released to the Internet for public comments on September 4, 1996. The "frozen" JavaBeans specification combines the work of Apple, Borland, IBM, JustSystem, Microsoft, Netscape, Rogue Wave, SunSoft and Symantec and many, many others... We're very pleased to see the tools community swiftly embracing JavaBeans by announcing support for JavaBeans in their visual application builder tools.
Les plus utiles selon les utilisateurs :
- What are Java Beans?
- Why do I get a NullPointerException when loading a JAR file into the BeanBox?
- What is bean persistance property?
- What are externizable interface?
- What are the purpose of introspection?