When we hear the term application modernization, the immediate image that comes to mind involves modernizing twenty-five year old critical business applications written in COBOL. While this is still true and represents the bulk of work in this field, there are other growing areas of application modernization that businesses undertake. These include migrating more recent heavy-weight legacy applications based on technologies like JEE and Oracle Forms to the newer light-weight Spring Framework. Another emerging modernization area involves moving from older web user interface technologies like JSP to newer more robust technologies like Spring Web Flow, Adobe Flex, and Google Web Toolkit (GWT). Modernization also involves updating the web layer to support mobile devices like the iPhone. Regardless of the application modernization area, MyEclipse for Spring provides tooling to support a rapid migration strategy.
Modernizing Existing Legacy Systems
Interestingly, reading through the plethora of online technology sites, it’s easy to get the impression that today’s information systems are almost all web applications using Java or .Net on the back-end. The reality, of course, is that the bulk of critical business applications remain in the world of COBOL – and there are no signs those systems are going to change dramatically in the near term. What is changing with an elevated sense of urgency, however, is the recognition that businesses need to define an application modernization plan that preserves and renovates their critical business processes while at the same time reducing the operating and maintenance cost of their aging existing systems.
From a high level perspective, the plan involves starting with an “as is” analysis of the current system – e.g., understand the complexity, structure, business rules, nature, and intended use of what is typically a loosely understood and largely undocumented system. The next major step involves defining the path for the “to be” system. In most cases, the modernization migration path involves a practical incremental approach. In this incremental approach, we start by defining, publishing, and using key business functionality from the existing system through web services. Then, we develop individual functional areas with Java/Spring and migrate the application in functional blocks in a timeframe that the business and technical teams can handle.
Oracle Forms Systems
The process for migrating from an Oracle Forms system to a Spring Framework system will be similar to the COBOL legacy system migration strategy. However, the migration effort should be easier due to a probability that the system software will be understood for the most part and has documentation. The functional areas may be a little tricky to separate as Oracle Forms relies heavily on PL-SQL for implementing business and validation logic. For Oracle Forms, the web services will usually be thin wrappers that call the PL-SQL stored procedures.
The process for migrating from a JEE system to a Spring Framework system will be similar to the COBOL legacy system migration strategy. However, the migration effort should be easier due to a probability that the system is understood for the most part and has documentation. Also, the developers will already understand Java.
Using MyEclipse for Spring in the Migration Plan
MyEclipse for Spring provides tooling to accelerate the “to be” migration strategy – for both scaffolding the web layer and using the web services to access the existing legacy system, as well as, developing the functional areas for migration to Java/Spring solution.
Incremental Migration – Using Web Services
After web services are defined and exposed, we use the WSDL import capability of MyEclipse for Spring to quickly generate the Spring and JAX-WS infrastructure to support calling the web services. Once the web service infrastructure is generated, we use the MyEclipse for Spring scaffold capability to quickly scaffold any of a variety of web layer implementations (e.g., Spring MVC, Spring Web Flow, Adobe Flex, GWT, and iPhone) for any of the Java Beans created during the WSDL import process.
Incremental Migration – Developing Spring Services
Another feature of the WSDL import process is the generation of “contract-first” Java package shells. When the WSDL import process completes, we have code shells for Spring Services and JUnit test classes that would be implemented and tested by Java developers. MyEclipse for Spring also includes code assistants to help developers create and maintain Spring annotations for their Spring Services. Once the code is completed and the business is ready, only one line of code needs to change to switch from using the web service provided by the existing legacy system to the new Spring Service.
Modernizing the User Interface
For the desktop
This area of modernization has become more popular as we see robust RIA solutions mature in the marketplace (e.g., Adobe Flex, Spring Web Flow, Google Web Toolkit, etc.). MyEclipse for Spring simplifies this modernization process through its scaffolding capabilities. Starting from a variety of sources including data schemas, JPA entities, and Java Beans, developers scaffold the web layer with the new user interface technology. From there, developers use the scaffold as either a starting point for building the complete user interface against the back-end or as a reference implementation template for coding the user interface with the chosen technology.
For mobile devices
Similar to its help for desktop web applications, MyEclipse for Spring simplifies modernization process for the iPhone through its scaffolding capabilities and for other mobile devices with small changes to context files and style sheets. Again, developers use the scaffold as either a starting point for building the complete user interface against the back-end or as a reference implementation template for coding the user interface with the chosen technology
Try it Yourself
MyEclipse for Spring is available for a free, 30-day trial. Accelerate your application modernization process by downloading from http://www.myeclipseide.com/module-htmlpages-display-pid-4.html.
Posted on Aug 19th 2010