HATS Environment Overview

HATS applications are deployed on an application server, latest version of HATS supports Apache Geronimo, Oracle WebLogic along with IBM WebSphere application server and portal. HATS application end-users initiate a transaction by entering a URL in a browser. This request travels by a TCP/IP network, the request from the client machine goes to WAS and then to HATS application, HATS application is a standard WebSphere application.


Standard HATS system environment.

The HATS application on WAS connects to the IBM 5350, 3270 or VT terminal can generate web based graphical interface on the fly, it can also combine screens, change workflows, execute macros and perform many different modernizations based on the screen customizations and global rules. Global rules are part of the default rendering approach of the HATS.

These global rules allow recognition or patterns and transformation of the input fields from host. Rules can be defined for the entire project or specific to a certain host screen.

HATS engine checks each host screen against the list of screen events. HATS has following two types of events,

  • Application events
  • Screen events

Application events are the events that are fired automatically by HATS, they are error events or busy event that is fired by HATS engine, when the host is busy.

Screen customization is a very important concept in the development of a Rational HATS based modernization project. HATS engine decides which set of actions to take when a specific host screen is encountered based on defined screen recognition criteria.

Power of Global Rules in HATS

For modernization of green screen legacy applications, pattern recognition and transformation of host input fields can be achieved by HATS global rules, Global rules can work with customized and non-customized (default rendered) screens. They can be defined at project level and screen level both.

In a situation where project-level and a screen-level global rule are both defined for the same field, the screen-level rule has higher priority.

Project-level global rules are really global for the HATS application; they are effective in screens both transformed by the rendering set, and by custom transformations. This enables entire application to recognize a particular host screen pattern without modifying any of your screen level transformations.

A global rule contains a configured recognition pattern and a transformation fragment. The pattern configuration states what kind of content to look for on the host screen. It transforms specific fields or all fields of a certain size, or those adjacent to a string you specify.
More effective use of global rules is possible when host application has uniformity along the complete application, like all F4 Lookup fields have an identification symbol (e.g “ -> “)  or word on host.



Following are few examples of global rules applied by the HATS, these can be applied once and users can witness the impact on all over the system.

Look Up Icon

We can create a rule in our HATS application to replace all appearances of “->” to an icon (e.g. Magnifying Glass) on clicking this icon HATS will send some command or function key to host (e.g. F4). This can be used to open a lookup window like following.



Clicking one row from the popover lookup window fills the corresponding field on the parent page.




Month Picker

We can create a rule to put all fields with some identification for being a month (e.g. “M/Y”) to put an icon with them.


When user clicks a month it is auto inserted into the corresponding text field.



Date Picker

Date pickers can be applied to the complete application using global rules, but there has to be some identification on host application to let HATS know where it should generate a date picker icon.


Clicking icon will open a JavaScript date picker, date chosen on the date picker will be auto inserted into the corresponding text fields.

Boolean Inputs

A global rule can be created to display a yes/no drop down with every field with some identification (e.g.” y/n”)



Global theme

We can apply a global theme with header, footer and background, this theme applies to all the screens of the application in one go.



Menu Items

Global rules using HATS default rendering can modernize the look and feel of the menu items across the application.





Sub files and tables,

Sub files and tables can also be modernized with improved look and feel by using global rules.



Function Key Button

We can create global rules to modernize all function key indications to buttons styled with CSS, but there has to be a consistency among function key and its text or purpose. (i.e. F1 has to be used for help for the entire application and F4 has to be only used for prompt everywhere in the application)

If a green screen application fails to provide such consistency the HATS will have difficulty in applying the correct icon on the button.

Also the text associated with the Function key has to be of approximately an average length so that the modernized button can hold the text else the text may overflow from the button, as we can only make button of a fixed width using a global rule. A work around to handle this overflowing text is by chopping off some part of the lengthier text caption.




Grids and drop downs

Global rules can globally apply table/grid themes and let us produce drop down input fields to perform actions on the table records.



Rational HATS applications on Apache Geronimo server

IBM Rational HATS applications are always known to be developed for IBM WebSphere Application or Portal Servers. Now we can develop, test, and deploy HATS web applications for the Apache Geronimo web application server along with Tomcat web container.

Apache Geronimo is an open source server runtime that meet the needs of enterprise JAVA developers and system administrators.

Downloading and Installing Geronimo Server

Download and install Geronimo server with the Tomcat web container:

  1. Download Apache Geronimo from here http://geronimo.apache.org/downloads.html.
  2. Extracting the .zip or .tar files and install it.
  3. Run the server from a command line window by changing the directory to geronimo_home/bin and entering the command: geronimo run.

The Geronimo Eclipse Plugin (GEP) provides integration between Eclipse, its Web Tools Platform (WTP) project, and Geronimo that enables you to utilize WTP features to develop, test, and deploy applications for the Apache Geronimo server using Rational SDP.

Install the Geronimo Eclipse Plugin (GEP), GEP version 2.2 has server adapters for version 1.1.x, version 2.0.x, version 2.1.x, and version 2.2 Apache Geronimo servers.

Configure Apache Geronimo as a server in Rational SDP for HATS test environment:

  1. At the Rational SDP menu bar, click Window > Preferences.
  2. In the left panel, expand Server section.
  3. Click on Runtime Environments.
  4. At the panel ‘Server Runtime Environments’, click Add here.
  5. In the New Server Runtime Environment dialog box, expand the Apache folder.
  6. Select the version of the Apache Geronimo server.
  7. Click Next to go to the panel, point to your local Geronimo server. In the field ‘Application server Directory’ enter the folder where the Geronimo server files are extracted.
  8. Click Finish.
  9. Click OK to close the panel ‘Preferences’.

After these steps, now we can create HATS applications within Rational SDP for Apache Geronimo servers.

Considerations / limitations for Geronimo servers

There are some differences between HATS web applications on Apache Geronimo server as compared to WebSphere Application Server. For instance, only single HATS web application is supported per .ear file on an Apache Geronimo server while WAS can run many.

Research Courtesy: Rafay Mirani (Rafi-u-Rehman)


Testing and Deploying HATS Applications on Apache Geronimo Server from Asif Hussain on Vimeo.

Enhance IBM Rational HATS Horizon with Web Services

Enhance IBM Rational HATS Horizon with Web Services from Asif Hussain on Vimeo.

Modern applications with the help of Web Services have appropriate mechanism to communicate with other Applications, a capability that is practically absent in legacy Green Screen applications. IBM Rational HATS® fully supports Service Oriented Architecture to develop and consume Web Services that can be used to get the data back and forth from & to the Green Screen Applications.
Learn how the platform independent Web Services, can be initiated and consumed within IBM Rational HATS®. The webinar also includes a technical demonstration of Web Service implementation and a Case Study of SOA enablement for IBM i Green Screen Applications using HATS®, primarily through Web Services that improved the organization’s efficiency by 85%*

The webinar will discuss the following:
Overview of IBM Rational HATS®
Overview of Service Oriented Architecture (SOA)
Overview and types of Web Services
SOA enablement for IBM i Green Screen Applications using HATS® – A Case Study
Technical Demonstration: Web Service implementation in HATS®

Menus Implementation with IBM Rational HATS – Webcast

Menus Implementation with IBM Rational HATS – Webcast from Asif Hussain on Vimeo.

With the enhancements in Computing and Human Computer interfacing, GUI has been extended to include various input mediums like Keyboard, Mouse, Light Pen, Touch Screen, etc. Whatever the device is, a modern interface is certainly incomplete without the implementation of “Menus”. Menus are essential part of UI design as they help a user in navigation and taking desired decisions on the interface.

Green Screen applications can be modernized according to latest UI trends with the help of IBM Rational HATS. Royal Cyber’s unique, innovative solution transforms Green screen applications for any medium, with the help of many Widgets, Controls, Function Keys, Utilities, Web Services and many types of Menus. Learn why the Menus are important. Explore how to use various types of Menus like Static, Dynamic, Tree, Pop-up, etc in IBM Rational HATS. Remember, a user friendly application is a key success factor for organizations to attain best ROI.
(The webinar included the demonstration of a menu development in HATS)

Royal Cyber Webinar – Green Screen Applications in Mobile Era

Royal Cyber Webinar – Green Screen Applications in Mobile Era from Asif Hussain on Vimeo.

IBM i and z series applications that have passed the test of time are hard to replace because of many factors including reliability, cost, training, time, etc. However, to gain or maintain competitive edge, it is important for organizations to follow newer technological trends. Offering solutions on Mobile devices inarguably is the most critical need of the day. Royal Cyber’s unique, innovative solution levitates your Green screen applications to latest mobile gadgets, irrespective of the technology, device, O/S and platform. Solution offered on mobile are modernized to meet the current UI trends without any compromise on performance and security.
Learn why it is important to have Mobile devices support of the Green Screen applications to your solution armory to attain maximum business and technical benefits. This webinar will demonstrate the benefits and procedures to extend the legacy green screen applications to latest mobile devices like cell phones, smart phones, tablets, bar code readers, PDAs, etc.

Smarter HATS web applications that automatically respond according to the screen

Smarter HATS web applications that automatically respond according to the screen from Asif Hussain on Vimeo.

Transform your legacy green screen applications into web based applications, accessible from all devices without any compromise on speed and quality, with short development time. This modernization enhances the business portfolio drastically resulting in best ROI.
Experience the art of our unique HATS Responsive Design development that adjust automatically to any resolution, making the system best fit for all the devices and platforms.

Royal Cyber HATS Distance Learning

Royal Cyber HATS Distance Learning, Session I from Asif Hussain on Vimeo.

Royal Cyber HATS Distance Learning, Session II from Asif Hussain on Vimeo.

Royal Cyber HATS Distance Learning, Session III from Asif Hussain on Vimeo.

Royal Cyber HATS Distance Learning, Session IV from Asif Hussain on Vimeo.

Explore the Technology that quickly transforms your 3270 and 5250 green screen applications to intuitive Web, portlet, rich client or Mobile device user interfaces, and extend 3270, 5250, and VT green screens as standard Web services.