Rapid Application Development for the Enterprise

Rapid application development tools are great. Visual Basic, Delphi, etc. are great at cutting development time for complex applications through their use of reusable components.

Reusable components (I will refer to them as "controls" from here on) are simply pre-built pieces of programming code designed to perform a specific function. When designing an application in a visual environment, controls can be quickly dropped into the design, and modified to fit the task at hand. Most of the controls you'll find are designed to handle such tasks as pushbuttons, menus, text labels, and so forth. As a developer, you only need to write code to "glue" them into your application, and develop the interactions between controls.

Recently, programmers have been searching for some way to create and reuse components in the Java language. Java holds great promise, but the early releases lacked any method for creating reusable controls, and thus caused extended development times for applications. Sun Microsystems, the creators of the Java language, have at last recognized this need, and have released the Java Beans Component Architecture. Java Beans are, quite simply, reusable controls written in Java, for Java application development.

Beans are "capsules" of code, each designed for a specific purpose. The advantage of Java Beans over standard programming controls is that Beans are independent. They are not specific to operating systems or development environments. A Bean created in one development environment can be easily copied and modified by another. This allows Java Beans greater flexibility in enterprise computing, as components are easily shared between developers.

Java Beans are best put to use by visual developers. In a visual design environment (for example, Symantec's Visual Cafe Pro, this author's current tool of choice), an application interface is developed on a "form" or client window. A toolbox contains all the controls (Beans) which are dropped onto the form through simple drag and drop procedures. As the controls are dropped onto the form, the development environment grinds out the necessary code, When the interface is finished, the developer can set about creating the actual interactions between controls and the application as a whole. An exciting concept behind Beans springs from the fact that an application created in Java can be used as a Bean, which can be used to build other applications. As you can imagine, this circle of application to Bean and back can make developing large-scale applications much easier.

Some may wonder why anyone would use a Bean over a Java Class file. The strongest argument for a Bean over a Class is that Beans support introspection. That is, they allow the development environment to analyze the Bean, determine its properties and methods, and manipulate the Bean at design time instead of at run time.

The newest use of Beans is to create a bridge between Java and ActiveX. Several software companies are working on methods of quickly converting ActiveX controls to Java Beans (IBM's Visual Age, for example, is leading the pack in this area). Whereas Microsoft hoped to encompass Java into ActiveX, it appears that developers have different ideas and are churning out a wide variety of conversion tools to pull ActiveX into Java.

Java Beans are not a cure for all your programming ills, though. Beans are great for developing interfaces and basic applications, but for working with JDBC and SQL, text-based hand coding is your best bet.

If you're a visual developer looking to migrate to Java, you'll find that Java Beans will make the transition much easier. With Java Beans, Sun is proving that Java is poised to grow and become a powerful force in application development.

Applets - An applet is a mini-application developed in the Java language. Applets are commonly downloaded from the Internet and run on the user's machine. Lately, even full-scale Java applications have been referred to as applets.

IDE - Integrated Development Environment. Usually a visual-style programming application. Common IDE's include Visual Basic, Delphi, and Symantec's Visual Café

Java - A programming language, developed by Sun Microsystems, which is designed to be run on any type of operating system. Applications developed in Java are "Written once, run anywhere".

JDBC - Java Database Connectivity. This allows Java applets/applications to read/write/modify data in any of the supported JDBC database formats.

SQL - Structured Query Language (or Standard Query Language, depending on who you ask). SQL is a language used to "ask questions of" a database. Through SQL, an application makes specific requests for information, and the database relays that information back to the application.