Introduction

The Host Access Transformation Services (HATS) Studio offers many tools for creating and customizing HATS applications. You might find, however, that your HATS application requires some additional function that you cannot add using the tools in HATS Studio and IBM Rational Studio. This Programmer's Guide explains several ways that you can extend your HATS application with additional programming.

This Programmer's Guide assumes that you are familiar with basic HATS concepts such as:

• How HATS processes host screens

• Configuring a transformation using components and widgets

• Events and actions

• Using global variables

• Recording a macro

• Creating an Integration Object from a macro

• Using Rational Studio to create Java^(TM) 2 Enterprise Edition (J2EE) applications

If you are not already familiar with any of these topics, refer to the information about them in HATS User's and Administrator's Guide so that you will have the necessary background to make good use of the information in this book. You should also be familiar with using Rational Studio to create J2EE applications.

This Programmer's Guide describes ways to enhance your HATS application by programming. You can:

• Add business logic classes to be invoked as an action when an event occurs. You can also create custom logic to aid in recognizing host screens. See Adding business logic.

• Add new host components or widgets to be used in transformations by extending the existing host components and widgets. See Creating custom components and widgets.

• Perform several programming tasks with Integration Objects. See Programming with Integration Objects and Integration Objects - advanced topics.

• Make one or more Integration Objects available as a Web service, which makes them available for use by other applications. See Creating Web services.

• Create a HATS Enterprise JavaBean (EJB) project, which encapsulates interactions with host applications and can be used by other HATS applications or Java programs. See Creating and Using a HATS EJB application.

• Create your own plug-ins for Web Express Logon. See Creating plugins for Web Express Logon.

• Enhance the capabilities of your HATS portlets. See Programming in HATS portlets.

• Use the HATS bidirectional API to work with the orientation of screen elements in applications that use bidirectional code pages. See Using the HATS bidirectional API.

Code examples

There are code examples throughout this Programmer's Guide. These examples illustrate the use of the objects or APIs introduced in the adjoining sections. The examples might or might not work if you copy them from the book into your application.

There are two longer examples that are not included in the PDF version of this book. The following examples are available in the HTML version:

• An example plug-in for Web Express Logon

• An example of a customized Integration Object template

Use the Rational Studio help system (click Help > Help Contents from HATS Studio, or click Start > Programs > IBM WebSphere HATS 6.0 > Library > Studio Help System to view the documentation without starting HATS Studio) to view these examples.

Using the API documentation

The HATS API reference documentation is useful for many programming tasks. This documentation is provided in the HATS Information Center at http://publib.boulder.ibm.com/infocenter/hatsv6/index.jsp.. Refer to this documentation when you need information about, and examples of, any of the Application Programming Interfaces provided with HATS.