Installing the JavaBeans Development Kit (BDK)

JavaBeans technology is the component architecture for the Java 2 Platform, Standard Edition (J2SE). JavaBeans components (beans) are reusable software programs that you can develop and assemble easily to create sophisticated applications. The technology is based on the JavaBeans specification and components or beans are reusable software components that follow simple naming and design conventions so they present a standard interface to other beans, programs, and tools. The installation of the "JavaBeans Development Kit involves" the following.

1. The JavaBeans Development Kit (BDK) downloads into a single file.
2. You will need to execute the kit (in Windows) or unpack this file (in Unix) in order to install the complete BDK.
3. Unlike the Java Development Kit (JDK), none of the BDK components are optional, so the installation is very simple.
4. Select the platform you are using to install the BDK.

• Installing the BDK on Windows Platform
  After downloading the Windows version of the BDK, locate the file JavaBeans Architecture: DBDK Download on your hard drive. (The end portion of the filename refers to the date that this version of the BDK was updated. Depending on the update status of the BDK, the file you downloaded may have a slightly different name.) To install the BDK from this self-executing file, double click the file icon in the Windows Explorer. This will start the InstallShield Wizard program. The InstallShield Wizard will guide you step by step through the installation process. However the BDK is "pure Java" and should run on any JDK 1.1 enabled system. The BDK includes a file named README.jsp that is located in the main Bdk directory. Be sure to read this file to find out additional information regarding the version of the Beans Development Kit you have installed.

To prepare for installing the JavaBeans Development Kit (JBDK) on a Windows system, follow these prerequisite steps:

1. Verify Java Development Kit (JDK) Installation
   • Requirement: JBDK requires the JDK as it provides the runtime and development environment for Java applications.
   • Steps:
     • Check if the JDK is installed by running `java -version` and `javac -version` in a Command Prompt or Terminal.
     • If not installed, download the latest JDK from the Oracle website or OpenJDK, and install it.
     • Configure the `JAVA_HOME` environment variable to point to the JDK installation directory.
     • Add the JDK's `bin` directory to the `PATH` environment variable for easy access to Java commands.
2. Check System Requirements
   • Requirement: Ensure your Windows system meets the requirements for JBDK, such as sufficient RAM, disk space, and compatibility with your JDK version.
   • Steps:
     • Check the documentation for the specific JBDK version for hardware and software requirements.
     • Update Windows to the latest version to ensure compatibility.
3. Install a Java IDE (Optional)
   • Requirement: Although not mandatory, an Integrated Development Environment (IDE) like Eclipse, IntelliJ IDEA, or NetBeans enhances the development experience.
   • Steps:
     • Download and install your preferred IDE.
     • Configure the IDE to recognize your JDK installation.

By completing these steps, you will ensure your system is ready to install and use the JavaBeans Development Kit effectively.

After downloading the Unix version of the BDK, locate the file
JavaBeans Architecture: BDK Download from Oracle on your hard drive. (The end portion of the filename refers to the date this version of the BDK was updated. Depending on the update status of the BDK, the file you downloaded may have a slightly different name.) To install the BDK from this file, unpack the release to a directory of your choice by executing the following command:

sh bdk_month_year.sh

The BDK includes a file named README.jsp that is located in the main Bdk directory. Be sure to read this file to find out additional information regarding the version of the BDK you have installed.

If you have not already, you can download the JavaBeans Development Kit (BDK) from Oracle. Download Oracle BDK
Did your installation of the BDK go as you expected?
Visit Oracle's "JavaBeans Component API" page to have additional questions answered.
JavaBeans Component API

JavaBeans is a reusable software component model in Java, designed to enable the creation and assembly of modular components. Its components are made up of the following key elements:

1. Properties
   • Definition: Attributes of the JavaBean, which control its behavior and appearance.
   • Types:
     • Read/Write Properties: Both getter and setter methods are available.
     • Read-Only Properties: Only getter methods are provided.
     • Write-Only Properties: Only setter methods are provided.
   • Implementation:
     • Properties follow a naming convention with get and set methods (e.g., getPropertyName and setPropertyName).
2. Events
   • Definition: Mechanism for components to communicate and respond to changes.
   • Components:
     • Event Source: The JavaBean that generates an event.
     • Event Listener: An object that listens and responds to the event.
   • Implementation:
     • Beans use the Java Event Delegation Model, employing interfaces and listener classes.
     • Example: addPropertyChangeListener and removePropertyChangeListener methods allow dynamic event handling.
3. Methods
   • Definition: Functions that define the behavior of the JavaBean.
   • Types:
     • Public Methods: Accessible to other classes for interaction.
     • Helper Methods: Often private or protected, used internally by the bean.
   • Implementation:
     • Public methods provide the logic for the Bean's functionality, adhering to naming conventions for introspection.
4. Persistence
   • Definition: Ability to save and restore the state of a JavaBean.
   • Mechanism:
     • JavaBeans support persistence by implementing the Serializable interface.
     • States can be stored and retrieved from files or databases.
   • Example: Using ObjectOutputStream and ObjectInputStream for serialization.
5. Introspection
   • Definition: Process of analyzing the Bean's design patterns to expose its properties, methods, and events.
   • Mechanism:
     • JavaBeans rely on the Introspector class from the java.beans package.
     • Tools or frameworks can dynamically discover properties, methods, and events of a Bean.
   • Usage: Enables design-time tools (e.g., IDEs) to interact with and manipulate the Bean.
6. Customization
   • Definition: Capability to modify a Bean's properties through user-friendly interfaces.
   • Mechanism:
     • Implementing custom property editors or using tools to generate UI for properties.
   • Example: A Bean used in a GUI application may allow a developer to set properties like colors or fonts through an IDE.
7. Support for Constrained and Bound Properties
   • Bound Properties:
     • Notify listeners when their values are changed.
     • Example: A PropertyChangeEvent is fired to listeners.
   • Constrained Properties:
     • Allow vetoing of changes to a property.
     • Example: Using a VetoableChangeListener to prevent invalid values.

These components make JavaBeans versatile and well-suited for modular development, allowing developers to design reusable and customizable software components.
In the next lesson, the BDK (Bean Development Kit) will be introduced.