From Green to Glory

WebFacing works by converting data description specifications (DDS) and user interface manager (UIM) source into Web pages at development time, generating Web representations of DDS constructs using Java* Server Pages (JSP) and XML. HATS transforms the 5250 datastream dynamically at run time without requiring a program's display file source.

Both tools have many new features in V7.0 - the best being that you no longer have to choose between them. This article will address the new HATS/WebFacing interoperability features in detail, along with some other enhancements in this release. For the quick highlights, see "The What's New Top 10".

WebFacing and HATS Interoperability
Prior to version 6.0.1, while most of the System i world was excited by the innovative WebFacing technology, some developers wept in the corner because they couldn't take advantage of it. These developers had applications from different vendors, both with and without DDS source. If they tried to access screens whose display files hadn't been converted, their applications would end in a runtime error and they'd have to give up on using WebFacing and try to find another way to move their applications to the Web.

WebFacing 6.0.1 came to the rescue. With i5/OS* V5R4, users could enable their runtime environments for dynamic datastream transformation based on HATS technology, bringing to an end "DDS not converted" runtime errors. Developers who wept before started to cheer up. While they were happy with the new capabilities of the dynamic transformation, they longed for customization options to further improve the default transformation. They wanted a better UI. Those familiar with HATS wanted to use the customization tools provided by HATS directly. Those who used both WebFacing and HATS for their projects wanted to seamlessly merge the two.

In V7.0, users can continue accessing system screens or 5250 applications that haven't been Web-enabled as in version 6.0.1, or they can use the new linked HATS/WebFacing project to directly mix HATS and WebFacing applications. The new linked projects let users enjoy many customization options only available in a HATS project. For example, they can use HATS macros to automate application execution and control application flow. They can also use different rendering patterns to improve the usability and attractiveness of screens rendered by HATS.

This new linked HATS/WebFacing project is also good news for HATS developers, who can now take advantage of many unique WebFacing features. For example, WebFacing converts display files to JSP. HATS developers can now, through JSP programming, do unlimited detailed and complex application customization. For applications that have display files not easily customizable by HATS, they can use WebFacing to render just those applications and let HATS handle the rest. Additionally, WebFacing handles data validation in the browser, reducing server side calls.

Let's take a quick look at how to create a linked HATS/WebFacing project (see Figure 1). To accomplish this, WebFacing provides a new project type, HATS/WebFacing-enabled project, which is the WebFacing side of the application. By creating a HATS/WebFacing-enabled project, users can convert the 5250 application source files from a System i environment into a standard Web format. Note that HATS/WebFacing-enabled projects are designed to work in conjunction with HATS projects and can't be run standalone. But users can still use all of the customization capabilities provided to regular WebFacing projects, such as Web Settings.

Afterward, the HATS Toolkit can Web-enable an application where the DDS source is unavailable. When users create a HATS project, they can use either the Telnet server or the WebFacing server to connect to the target host system.

Using the WebFacing server removes the need for online transaction processing on i5/OS V5R4. Even if the Telnet server is used during a HATS project creation, the linked project will connect to the target host system through the WebFacing server, because WebFacing projects always use the WebFacing server.

Next, use the Linked HATS/WebFacing Project wizard to link the HATS/WebFacing-enabled project and the HATS project to create a single enterprise application. This linked HATS/WebFacing application can be tested on WDSc's built-in test environment, then deployed to WebSphere Application Server (WAS) for production.

This linked application interoperates seamlessly. Within the same application, WebFacing performs DDS source transformation, while HATS performs 5250 datastream transformation. One user job is created for one browser session. Out of the box, two new WebFacing styles provide a unified look with pages rendered by HATS.