They may also have newer systems already written in Java, or have a desire to take advantage of Java for less business-oriented new application development.
A typical example of how this situation materialises for the IT Manager is delivering Web access to legacy applications and data. Organisations need to deliver their existing COBOL business logic and extend it to the Web. How can you integrate new Web development technologies with existing legacy code and reuse rather than rewrite existing business logic? The secret lies in unleashing the power of the Enterprise Java Bean (EJB).
In the past, the interfaces and capabilities of Web Application Servers differed considerably. A common attribute was that they typically targeted Java or C++, making it difficult for COBOL applications to use them. In recent years, with the growing prominence of the EJB model, Application Servers now support EJBs. The EJB model can deliver existing COBOL business logic and utilise Java classes from COBOL to establish interoperability between Java and COBOL.
While Java and COBOL interoperability has long been possible, this doesn't mean it has been easy. There is a mechanism built into the Java platform that allows Java methods to call non-Java (or native) methods - the Java Native Interface (JNI). Although the JNI is powerful, it's not intuitive, especially for COBOL programmers. JNI lets COBOL and Java mix easily, and COBOL applications can be wrapped as EJBs. This creates an infrastructure that provides a strategic platform for extension and maintenance of legacy applications.
Calling legacy COBOL programs from Java and EJBs provides a fast way of making COBOL business logic available to Java programs.
Using toolsets and wizards, developers can easily create COBOL-wrapped EJBs and COBOL classes for use as an EJB. By calling on an organisation's business logic within COBOL-wrapped EJBs the benefits of an Application Server environment are combined with the performance gain of compiled COBOL code. So to answer the question, How can you integrate new Web development technologies with existing legacy code and reuse rather than rewrite existing business logic? Unleashing the power of the Enterprise Java Bean (EJB) to leverage the investment you have in your existing COBOL applications. Keith Mante is the country manager at Micro Focus Australia.