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Java[tm] IDL is a technology for distributed objects--that is, objects interacting on different platforms across a network. Java IDL is similar to RMI (Remote Method Invocation), which supports distributed objects written entirely in the Java programming language
Learn about how to work with Java IDL.
Try a quick Java IDL tutorial.
This topic introduces the basics of writing a CORBA client applet. An applet is a Java program to be included in HTML pages and executed in Java-enabled browsers. Developing a CORBA client applet is very similar to developing a CORBA client application, except that in the applet the code appears in the init() method rather than in the main() method. You can run the applet from the Applet Viewer or from a Web browser that is compatible with J2SE v1.3. The steps in this lesson are:
This topic walks you through running the server and client program that together make up the "Hello World" application or applet.
The example server consists of two classes, the servant and the server. The servant, HelloServant, is the implementation of the Hello IDL interface; each Hello instance is implemented by a HelloServant instance. The servant is a subclass of _HelloImplBase, which is generated by the idlj compiler from the example IDL. The servant contains one method for each IDL operation, in this example, just the sayHello() method. Servant methods are just like ordinary Java methods; the extra code to deal with the ORB, with marshaling arguments and results, and so on, is provided by the server and the stubs.
To invoke an operation on a CORBA object, a client application needs a reference to the object. You can get such references in a number of ways, such as calling ORB.resolve_initial_references() or using another CORBA object (like the name service). In previous sections of this tutorial, you used both of these methods to get an initial object reference.
Applet Code Sample
To enable the Hello World Tutorial to run on two machines, follow the steps as directed in the tutorial, with the following changes. This tutorial was written for the Java (tm) 2 Platform, Standard Edition (J2Se(tm)), version 1.3. In this example, the client, stubs, and skeletons are located on the client machine, and the server and name server are located on the server machine. This scenario can be changed to meet your needs and is provided simply as an introduction to one way this can be accomplished.
To help you learn how to use the Java Debugger (JDB), here are two tutorials:
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