User Interfaces on the Server

Oracle8i furnishes all core Java class libraries on the server, including those associated with presentation of user interfaces (java.awt and java.applet). It is, however, inappropriate for code executing in the server to attempt to bring up or materialize a user interface in the server. Imagine thousands of users worldwide exercising an Internet application that executes code that requires someone to click on a dialog presented on the server hardware. You can write Java programs that reference and use java.awt classes as long as you do not attempt to materialize a user interface.

When building applets, you test them using the java.awt and the Peer implementation, which is a platform-specific set of classes for support of a specific windowing system. When the user downloads an applet, it dynamically loads the proper client Peer libraries, and the user sees a display appropriate for the operating system or windowing system in use on the client side. Oracle8i takes the same approach. We provide an Oracle-specific Peer implementation that throws an exception, oracle.aurora.awt.UnsupportedOperation, if you execute Java code on the Oracle8i server that attempts to materialize a user interface.

Oracle8i's lack of support for materializing user interfaces in the server means that we do not pass the Java 2 Compatibility Kit tests for java.awt, java.awt.manual, and java.applet. In the Oracle RDBMS, all user interfaces are supported only on client applications, although they might be displayed on the same physical hardware that supports the server--for example, in the case of Windows NT. Because it does not make sense for the server to support user interfaces, we exclude these tests from our complete Java Compatibility Kit testing.

A similar issue exists for vendors of Java-powered embedded devices and in handheld devices (known as Personal Java). Future releases of Java and the Java Compatibility Kit will provide improved factorization of user interface support so that vendors of Java server platforms can better address this issue.

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