JavaBeans Section Index | Page 6
Can I assume that the order event targets are registered with a JavaBean will be the order they will be notified?
Order of delivery to targets is implementation dependent! Never assume that order of addXXXListener() calls determine order of delivery!
How can a visual development environment manipulate a JavaBean?
While every tool varies, in general, they can:
Determine what methods, properties, and events it supports
Change its properties
Connect events between components
Save / restore its state to / fro...more
How can I treat my bean differently at design time?
The static isDesignTime() method of the Beans class allows your bean to act differently at design time vs. at runtime, potentially freeing up CPU cycles for the designer. For instance, if the purp...more
How do I create an event to be used in a JavaBeans component?
New events must subclass the java.util.EventObject class. If they do not, a development environment will not be able to find out the necessary information from the component using the event.
See H...more
How do I define a listener to be used for a JavaBeans event?
JavaBean listeners must extend the empty java.util.EventListener interface. If they do not, a development environment will not be able to find out the necessary information from the component need...more
How do I package a component to be used as a JavaBean?
Beans can be packaged in JAR, ZIP, other archives. Using the jar tool that comes with the JSDK, you would need to perform the following two steps:
Create descriptive text file called a manifest s...more
How do I restore a JavaBean from a saved version?
Instead of continually creating JavaBeans components and setting their state to some common setting, you can save what tends to be called a pickled version of the component, with the bean properti...more
I keep hearing about bean info. What is it?
The JavaBeans model provides a default way of looking inside a class to find out its properties and events it generates. If you would like to provide a different view to the development tool, then...more
What are the minimal characteristics for something to be a JavaBean component?
The only absolute requirement is that the component implement the java.io.Serializable interface.
Usually, you'll find the following, but they are not requirements from the strictest sense, only f...more
What is a JavaBean?
JavaBeans are reusable software components written in the Java programming language, designed to be manipulated visually by a software develpoment environment, like JBuilder or VisualAge for Java....more
What is necessary for a JavaBeans component to be an event source?
Components must implement add and remove listener methods (addXXXListener() and removeXXXListener())to maintain a list of targets and implement code to notify the targets when the event happens. C...more
What is the BDK?
The BDK is the Beans Development Kit. It is a freely available testing tool to try out your JavaBeans components within a BeanBox. While a good environment for learning about JavaBeans, it is not ...more
Are Enterprise JavaBeans and JavaBeans the same thing?
Enterprise JavaBeans and JavaBeans are not the same thing; nor is one an extension of the other. They are both component models, based on Java, and created by Sun Microsystems, but their purpose ...more
Why doesn't my bean work in other bean tools like BeanBox?
The JavaBean specification requires that all beans implement persistence
through the Serializable or Externalizable interfaces. Nothing more is required.
IBM interpreted the bean specification a b...more