The Java Extension Mechanism
for Support of Optional Packages
Note: Optional packages are the new name for what used to be known as standard extensions. The "extension mechanism" is that functionality of the Java 2 SDK and Java 2 Runtime Environment that supports the use of optional packages.Enhancements
Optional packages are packages of Java classes (and any associated native code) that application developers can use to extend the functionality of the core platform. The extension mechanism allows the Java virtual machine (VM) to use the classes of the optional extension in much the same way as the VM uses classes in the Java 2 Platform. The extension mechanism also provides a way for needed optional packages to be retrieved from specified URLs when they are not already installed in the Java 2 SDK or Runtime Environment.
The following classes play a role in the extension mechanism:
Located on the Java Software website: