Harry M. Sneed

Wrapping legacy COBOL programs behind an XML-interface

This paper describes the tools and techniques for encapsulating host COBOL programs with an XML interface. The legacy programs are divided into three classes - online programs, batch programs and subprograms. For each program type, a different wrapping technique and a different tool is employed. Online programs are transformed into data-driven subprograms which process an XML document. Batch programs are adapted to read and write XML documents. Subprograms are left unchanged, but their parameters are set from an XML document. By using XML to implement corporate portals, it has proven possible to reuse existing host programs within new intranet/Internet systems, thus reducing system development costs and development time by more than 60%.

Creating Web services from legacy host programs

An important prerequisite to connecting existing systems to the Web is the ability to link client programs on the Web site with server programs on the host. The host programs have not been conceived to run in an internet mode. They are either online transactions or batch steps. This paper describes a tool supported process to cut out selected sections of legacy code and to provide them with an XML interface. The same interface is used to generate a Java class, which creates XML messages returning from the server. This class is then built in to the package managing the Web site. In this way a consistent communication between the Web site and the server components on the host is ensured.

Estimating the costs of a reengineering project

Accurate estimation of project costs is an essential prerequisite to making a reengineering project. Existing systems are usually reengineered because it is cheaper to reengineer them than to redevelop or to replace them. However, to make this decision, management must know what the reengineering will cost. This contribution describes an eight step tool supported process for calculating the time and the costs required to reengineer an existing system. The process is derived from the authors 20 year experience in estimating reengineering projects and has been validated by several real life field experiments in which it has been refined and calibrated

Reverse engineering of test cases for selective regression testing

A problem arises in the maintenance of large systems when the links between the specification based test cases and the code components they test are lost. It is no longer possible to perform selective regression testing because it is not known which test cases to run when a particular component is corrected or altered. To regain that knowledge, it is necessary to restore the links between test cases and code. We describe two complementary approaches to achieving that goal of reverse engineering - one by static analysis and the other by dynamic analysis. The objective in both cases is to determine which test cases exercise which methods in which components in order to enable selective regression testing.

A pilot project for migrating COBOL code to web services

This paper describes a pilot project conducted to test the feasibility of constructing web services from existing mainframe COBOL programs. The project involved the use of four tools. The first tool, COBAudit, was intended to identify candidates for web services. The second tool, COBStrip, served to extract only that portion of the code required to fulfill the service. The third tool, COBWrap, wrapped the code extracted from original code and converted it to an executable component. The fourth tool, COBLink, connected the wrapped component to the web by generating a WSDL interface from either the COBOL linkage section or the original map definition. The tools were applied to a legacy life insurance system with more than 20 million lines of COBOL code running under IMS on the IBM mainframe.

Using XML to integrate existing software systems into the Web

The eXtensible Markup Language (XML) is not only a language for communication between humans and the Web, it is also a language for communication between programs. Rather than passing parameters, programs can pass documents from one to another, containing not only pure data, but control information as well. Even legacy programs written in ancient languages such as COBOL and PL/I can be adapted by means of interface reengineering to the process and to generate XML documents. This paper intends to describe the process and the tools required to accomplish that goal and to present three cases - one for online, one for batch and one for subprograms - to illustrate how XML may be used to integrate existing software systems into the Web.

An incremental approach to system replacement and integration

Business users have a problem in replacing existing business application systems. Well over 50% of all replacement projects fail. The systems have become much too complex and too much knowledge about them has been lost. It is nearly impossible to reconstruct the requirements. Therefore, this paper presents an incremental, integrative approach supported by bridging tools, which allows migrating without requirements. The basic premise is to first breakup the existing systems into separate, collaborating subsystems and then to either convert them, redevelop them or to wrap them one at a time. The key is the interaction of the subsystems with each other and with the database across platform boundaries. The new subsystems can coexist with the remaining old ones until such time that all of them have been replaced.

COB2WEB a toolset for migrating to web services

This paper describes a tool set for constructing web services from existing main frame COBOL programs. The first tool - COBAudit - is intended to identify candidates for web services. The second tool - COBStrip - serves to extract only that portion of the code required to fulfill the service. The third tool - COBWrap - wraps the code extracted from original code and converts it to an executable component. The fourth tool - COBLink - connects the wrapped component to the web by generating a WSDL interface. The tools are currently under test within a project for a German financial service with an insurance system of 25 million lines of COBOL code running under IMS on the IBM mainframe.

Offering software maintenance as an offshore service

This keynote is directed to the software service organizations in the emerging countries of Asia and South America as well as to outsourcing companies in Eastern Europe. It summarizes the sad state of many western user organizations caught in the legacy software trap and how eastern software shops can help them. The talk focuses on the processes, techniques and tools required to run a remote software maintenance operation, the legalities of maintenance contracts and the economics of outsourced services. The speaker shares his experience in how to establish a good customer relationship and how to charge the services in a way that is acceptable to both the customer and the service provider.

Linking legacy services to the business process model

The purpose of the work described here is to support the reuse of existing software systems in a SOA environment by linking a description of existing programs to the overlying business processes. It is one thing to technically wrap the legacy code. It is another matter to connect the code interface definition to the business processes. The SoftLink tool is under development to bridge that gap between the business model and the code reality. The crux of the solution is to identify the entry points to the application system and their parameters and to link them to the events in the business process via a WSDL interface. The method is illustrated here on a legacy COBOL application for processing customer orders. From that code interfaces to the events within the subject-oriented business process model are created via a semi-automated transformation. Future development will focus on linking Java and .Net systems as well. This will provide a better basis for the maintenance of SOA systems and allow impact analysis to traverse the border between model and code.