One modernizing tool for enhancing the display of your legacy programs is screen scraping. Basically, it entails current user interfaces from your IBM i 5250 green screens. Using a screen scraping tool as a channel between your legacy program and a modern display, screen scraping refreshes the original screen material from your program to show on a browser.
Still, screen scraping by itself doesn’t really benefit your application except for a contemporary appearance. The approach stays the same.
Does screen scraping differ from building a new user interface ?
Another approach to upgrade your legacy application is by creating a new user interface. This method modernizes screen content, yet like screen scraping it adds a little more. Your legacy apps will use scripts that not only interact with their original content but also grasp the goal of the screen shown. For your legacy application, for instance, you could have to negotiate numerous layers of menus to reach your order entering screen. A script can go through those menus behind the scenes and call upon the order entry screen for you to save you time and increase usability.
Stated differently, by creating a new UI, you can substitute a user interface that improves the functionality of the original heritage panel. To further increase order entry screen efficiency, you also choose to show consumer data including prior purchases.
Creating a new user interface is kind of an ad-hoc fix, much like screen scraping is. It adds little actual value since the application and its underlying business processes remain constrained.
Can you translate corporate tasks into callable services ?
For many companies, running mission-critical business processes falls on older systems. Changing market conditions and digital transformation projects, however, depend on their company operations being accessible to both current and new uses. This is made feasible by turning legacy apps into callable services.
Callable services are sets of coded logic available for usage in other applications. They employ a web service, a remote procedure call, or message exchange to do this. You can create callable services from business operations including customer order retrieval and discount computations.
You accomplish this by evaluating your current portfolio to find business functions either required by other programs or possible offerings. Modern software development technologies allow you then to create web services. In this sense, a new or existing application can just call the relevant web service when it requires the business capability of a legacy application.
Unlike some of the other methods on this list, turning business processes into web services skips the user interface. It also alters the application’s running dynamics. These days, these programs can interact and exchange data with other ones. You can also save your historical company operations and apply them in different projects.
How Does IBM i Application Migration Work?
Moving discrete pieces of capability to one or more apps is the legacy application modernization approach known as migration. Assume, for instance, that you run a traditional ERP program including finance out of several modules. You would decommission your current finance module using the migration approach and handle finances using another program.
Modernizing corporate functions is the essence of application migration; not apps. Starting with the most crucial corporate function, you can work progressively. In the always ongoing modernization process, this is a successful strategy.
Re-hosting: How does it go ?
Rehosting is putting your system in the cloud without changing its architecture. Those wishing to migrate fast or those with significant on-premises expenditures generally consider rehosting. Rehosting is also common for businesses whose applications consist of commercial or off-the-shelf applications they do not have to update or maintain or whose applications do not demand continual changes.
Rehosting, however, has little actual advantages in the contemporary market when companies must innovate to survive. This is so because, as innovators must create new features or internal solutions at speed—think of Amazon or any other current market leader. Rehosting without changes also has minimal utility. It is simply bringing the same old system to the cloud.
Is rewriting legacy IBM i applications a modernizing approach ?
Rewriting IBM i old applications is a modernizing method whereby new applications are created with current software development technology. Many companies tackle modernization by creating new applications from the ground up, basing their equivalent functionalities on their historical apps. Changing the apps to the Model-View Controller (MVC) pattern or such design will help you to upgrade your outdated architecture.
This method looks reasonable, but it can be problematic if you have to add more capabilities along the road. Including extra features raises the effort required. To do an effective rewrite, you have to treat scope extremely carefully.
Key goals of legacy application modernization are enabling interface with modern technology while using current resources. This implies that, should your program provide all the required capabilities, preserve it.
“Programming language conversion” is one approach toward doing this. This approach generates a modern language from your source code by use of a modernization tool. For instance, ranging from COBOL to Java.
Though this choice might solve some immediate problems, it is not long-term. This is because, in cases of incompatible languages specifically, the produced code is exactly the same as the original code. One may convert RPG to C# or Java as an illustration of this. An Object-Oriented paradigm does not fit the RPG procedural programming paradigm exactly. Your transformed code will so run inefficiently and call for tiresome maintenance. The rewriting effort is likewise influenced by the conversion tool efficiency.
Having said that, for big legacy projects when a complete rewrite is not feasible, programming language conversion can provide a basis.
