In-Depth

Swap Green Screens for a Web Interface in Under an Hour

IBM says its HATS tool can quickly expose mainframe applications to the Web

• By Stephen Swoyer
• 04/13/2004

Last October, IBM announced that it had taken the logical step of consolidating HATS and Host Publisher into a new release, called HATS 5.0. “This is accomplishing a couple of things: integrating HATS 4.0 and Host Publisher, putting in place a more comprehensive offering … so your options for taking a host application and externalizing it are more complete,” noted Mark Heid, program director for enterprise modernization at the company, at the time.

Since then, says Stan Dahl, WebSphere Brand Software Specialist with IBM reseller Mainline Information Systems, customers have expressed enormous interest in the combined offering. “I am selling it to banks, manufacturing companies, and utilities, I’m selling it to a publisher that is a world-wide institution that’s taking their existing applications and moving them across the network to all of their subsidiaries around the world, I am also talking to pharmaceutical companies,” he comments.

IBM positions HATS as a tool for enterprise environments that aren’t rich in IT talent (or can’t spare valuable IT resources) but which want to expose traditional green screen host applications in new interfaces. HATS applies presentation rules to green screens as they are encountered in a 3270 or 5250 data flow, and can also skip through green screens programmatically, bypassing extraneous screens. It also allows an organization to customize the presentation logic of host data by inserting corporate banners or other information into a flow. Finally, systems programmers can use HATS to consolidate several application green screens into a single Web view.

Even though HATS isn’t as customizable as the more powerful Host Publisher tool, says Mainline’s Dahl, it’s flexible enough to suit most customer requirements. Because it allows organizations to expose host applications without resorting to J2EE coding, it’s a popular choice for many customers.

“In Host Publisher, or even in the iSeries when you do Web facing, you do have a certain amount of coding to do, even though it’s macro-language-generated, you still have to tell it what you want to do with each of the fields,” he explains. “The HATS product is a template-driven solution, where you apply the basic rules for what you want to apply to your Web pages and how you wish them to perform, and point it to the green screens, the 3270 apps that you want to change, and it automatically goes through them and changes them for you dynamically on the fly, so there’s no real coding that you need to do.”

How well does HATS work and how quickly can it expose host applications? Dahl says that prospective customers often ask him to demonstrate the tool on their own mainframe applications. In many cases, he says, he can repurpose a host application in as little as 15 or 20 minutes, once his laptop is hooked up.

Now that the HATS and Host Publisher tools have been combined into a single product, says IBM’s Heid, enterprise customers can use HATS to rapidly expose mainframe applications, and—if they have J2EE coding talent on staff—then use Host Publisher to customize host applications. “If you’re buying HATS 5.0, you can set it up and install it, [and] within two hours you can provide the rules-based technology to the green screens and automatically convert them,” he explained. “And now you can also have the Host Publisher functions brought in and made available, so you can continue on from the customization scenario and begin to integrate other host back-ends and reconstitute how the data is shown.”

Elsewhere, says Jim Rhyne, a distinguished engineer and eServer tools and enterprise modernization architect with Big Blue, customers can use HATS’ WebSphere underpinnings to expose mainframe business processes as Web services, which can deliver genuine business ROI. “Why are people doing this? Why do they want to move to this Web services interconnect paradigm? Increasingly, they’re looking at software integration and process automation as key factors to being quick to market and being more efficient as a business, and that’s the part that WebSphere has to play in this,” he argues. “We see it as being the hub technology that supports software integration on the one hand and business process automation on the other.”

Mark Vanston, a program director with research firm META Group, says that even though IBM isn’t the only vendor shopping Web-services-ready host integration tools, it’s certainly seeing a lot more traction than many of its competitors. “If you’re a [Big] Blue-centric organization, if you’re a large organization, chances are you’re using the [WebSphere] application server, the Eclipse Studio, [and] a variety of different products to externalize [your host applications],” he agrees, noting that most traditional purveyors of host access or host integration technologies haven’t yet had a lot of success selling their next-generation spins on these technologies.

One reason for IBM’s success, speculates Mainline’s Dahl, is that HATS enables the same folks who understand the underlying business logic of host applications to rapidly expose them and get up to speed on Java, Web services, and other programming methods over time. “It allows you to go from COBOL to Java without changing languages right off the bat, and it makes a smoother transition for us older folks to not have to learn Java right now,” he observes. “I don’t have to learn Java—I can use this tool to do that, and learn as I go, by allowing the system to generate that code, and then I can examine that code to understand what it’s doing without having to write it natively.”