PowerBuilder developers can build clients that invoke the services of COM+ and third-party application servers, and build components (or objects) that execute business logic inside each of these servers.
J2EE servers
J2EE, the Java 2 Platform, Enterprise Edition, is the official Java framework for enterprise application development. A J2EE application is composed of separate components that are installed on different computers in a multitiered system. The following figure shows three tiers in this system: the client tier, middle tier, and Enterprise Information Systems (EIS) tier. The middle tier is sometimes considered to be made up of two separate tiers: the Web tier and the business tier.
Figure: J2EE client, middle, and EIS tiers
Client components, such as application clients and applets, run on computers in the client tier. Web components, such as Java servlets and JavaServer Pages (JSP) components, run on J2EE servers in the Web tier. The EIS tier is made up of servers running relational database management systems, enterprise resource planning applications, mainframe transaction processing, and other legacy information systems.
COM+
A PowerBuilder application can act as a client to a COM server. The server can be built using any COM-compliant application development tool and it can run locally, on a remote computer as an in-process server, or in COM+.
For more information, see Building a COM or COM+ Client
