J2EE.7.1 Introduction to Interoperability

The J2EE platform will be used by enterprise environments that support clients of many different types. Often, these enterprise environments will add new services to their existing enterprise information systems. These enterprise environments very likely will be using different hardware platforms and various software applications written in different languages.

Enterprise environments may leverage the J2EE platform to bring together applications written in such languages as C++ and Visual Basic. One or more of these existing applications may be running on a personal computer platform, while others may be running on Unix workstations. In addition, these enterprise environments may also be supporting standalone Java technology-based applications that are not directly supported by the J2EE platform.

The J2EE platform provides indirect support for various types of clients, different hardware platforms, and a multitude of software applications through its interoperability requirements. To an application component provider or system administrator in an enterprise environment, the interoperability features of the J2EE platform permit the underlying disparate systems to work together seamlessly. In addition, the platform hides much of the complexity required to join these pieces.

The interoperability requirements for the current J2EE platform release allow:

• J2EE applications to connect to legacy systems using CORBA or low-level Socket interfaces.

• J2EE applications to connect to other J2EE applications across multiple J2EE products. The J2EE products can be from multiple product providers or they can be from the same provider.

This specification allows J2EE applications to connect to EIS or legacy systems. At the current time, these connections may be accomplished using CORBA services or low-level socket interfaces.

In addition, this specification requires that J2EE applications be allowed to connect to other J2EE applications. These other J2EE applications may be running on other J2EE platforms. J2EE applications must also be able to connect and work with J2EE applications written by other application providers. In this version of the specification, interoperability between J2EE applications running in different platforms is accomplished through the HTTP protocol, possibly using SSL.

Future versions of this specification will require interoperability using IIOP to access enterprise beans. See the document Enterprise JavaBeans to CORBA Mapping , available at http://java.sun.com/products/ejb/docs.html for details.