Java rich internet applications (RIA) are applications that have traits similar to desktop applications, but are deployed via the Internet. Java RIAs may be developed and deployed as Java applets or Java Web Start applications.
- Applets - Java applets run in the context of a browser. The Java Plug-in software controls the execution and lifecycle of Java applets.
- Java Web Start applications - Java Web Start applications are launched via a browser the first time. They may subsequently be launched from a desktop shortcut. Once a Java Web Start application is downloaded and its security certificate has been accepted by the user, it behaves almost like a standalone application.
In the past, the decision of whether to deploy a Java rich internet application inside the browser as an applet, or outside the browser as a Java Web Start application, could significantly impact the design of the application. With the latest Java Plug-in, this decision has been greatly simplified.
Traditionally, applications construct their user interfaces, including the top-level
Frame, in the
main method. This programming style prevents easy re-deployment of the application in the browser, because it assumes that the application creates its own
Frame. When running in the browser as an applet, the applet is the top level container that should hold the user interface for the application. A top-level
Frame is not needed.
Use component-based architecture when designing your Java rich internet application. Try to organize its functionality into one or more components that can be composed together. In this context, the term "component" refers to a GUI element that is a subclass of the AWT
Component class, the Swing
JComponent class, or another subclass. For example, you could have a top level
JPanel which contains other UI components in it (like a combination of more nested JPanels and text fields, combo boxes etc.). With such a design, it becomes relatively easy to deploy the core functionality as an applet or a Java Web Start application.
To deploy as a Java applet, you just need to wrap the core functionality in an
JApplet and add the browser specific functionality, if necessary. To deploy as a Java Web Start application, wrap the functionality in a
Choosing Between Java Applets and Java Web Start Applications
The Rich Internet Applications Decision Guide contains detailed information to help you decide whether to deploy your code as a Java applet or Java Web Start application.
The Self-Contained Application Alternative
Self-contained applications provide a deployment option that does not require a browser. Users install your application locally and run it similar to native applications. Self-contained applications include the JRE needed to run the application, so users always have the correct JRE.
This trail discusses the development and deployment of RIAs and self-contained applications. See What's New for capabilities introduced in various versions of the client Java Runtime Environment (JRE) software.