Welcome
Developing
Developing EGL applications
Enterprise Generation Language (EGL) is a programming language that you can use to focus on business problems instead of software technologies. Within the Rational® development environment, you can use EGL wizards and other tools to write complex applications with minimal effort.
EGL Language Reference
The EGL Language Reference covers the fundamental use of the language, including its concepts, syntax, and keywords. This volume is intended for a developer writing EGL applications with some experience in procedural programming.
Logic parts
Program part
A program part defines the central logic in a runtime program.

Overview
Getting started
Installing
Upgrading and migrating
Developing
- Model driven development of EGL code
- Generating source code from UML models
  You can use transformations to create source code from a UML model. First you must create a transformation parameters file and then apply those parameters to a model.
- Generating the EGL Dependency Graph from EGL projects
- Generating Source Code from OpenAPI Documents
- Developing EGL applications
  Enterprise Generation Language (EGL) is a programming language that you can use to focus on business problems instead of software technologies. Within the Rational® development environment, you can use EGL wizards and other tools to write complex applications with minimal effort.
  - How to use this documentation
  - Additional information about EGL
    The most recent EGL documentation is in the Rational® Business Developer Information Center.
  - EGL Programmer's Guide
    The EGL Programmer's Guide covers using EGL within the Eclipse Integrated Development Environment (IDE), as well as some of the common programming tasks that EGL developers perform.
  - EGL Generation Guide
    The EGL Generation Guide covers the process of converting EGL code to Java™ or COBOL source code, including the processes and the files involved. This section is intended for a developer who will generate or deploy EGL applications.
  - EGL Language Reference
    The EGL Language Reference covers the fundamental use of the language, including its concepts, syntax, and keywords. This volume is intended for a developer writing EGL applications with some experience in procedural programming.
    - General syntax
    - System data parts
    - User-defined data parts
    - Logic parts
      - Functions
      - Program part
        A program part defines the central logic in a runtime program.
        Program properties
      - Library part
        Library parts support the sharing of functions and variables.
      - Service part reference
        Service parts provide requesters with access to the functions in the service. A requester can be a local or remote program, handler, library, or another service.
      - Interface part
        Interface parts provide access to a remote service, such as a web service.
      - ExternalType part
        ExternalType parts map EGL to external language elements.
      - Delegate part
        Delegate parts provide models for functions.
      - Stand-alone function part
        Stand-alone function parts support migration from languages that do not use libraries.
    - Correspondence between a JSON string and an EGL variable
      This topic describes the EGL record that corresponds to a JavaScript™ Object Notation (JSON) string. Other topics describe the functions (serviceLib.convertFromJSON() and serviceLib.convertToJSON()) that are used by a Rich UI developer to convert JSON data to or from a variable, as may be necessary to access a third-party REST service. A failure in either function causes a RuntimeException.
    - Correspondence between a JSON string and an EGL variable for zOS and IBM i
      This topic describes the EGL record that corresponds to a JavaScript Object Notation (JSON) string. This topic describes the functions—serviceLib.convertFromJSON() and serviceLib.convertToJSON()—that are used by an EGL developer to convert JSON data to or from a variable either for zOS or IBM i systems. A failure in either function causes a RuntimeException.
    - Special considerations for JSON support on IBM i:
    - Correspondence between an XML string and an EGL variable
      This topic describes the EGL record that corresponds to an Extensible Markup Language (XML) string. Other topics describe the functions (serviceLib.convertFromXML and serviceLib.convertToXML) that are used by a Rich UI developer to convert XML data to or from a variable, as may be necessary to access a third-party REST service.
    - EGL statements
    - EGL core system libraries and variables
    - Accessing data in EGL
      Whenever you access a data store in EGL, the data goes into a record.
    - Applications with user interfaces
    - VisualAge® Generator compatibility
    - Appendices
    - Importing product-supplied projects
      You can click a link to download the current version of Rich UI projects. The capability is useful if you deleted a project or want a clean version.
  - Rational® COBOL Runtime Guide for zSeries®
    This manual provides information about customizing and administering the IBM® Rational® COBOL Runtime.
  - Rational® Business Developer EGL Server Guide for IBM® i
    This manual provides information about customizing and administering EGL Server for IBM® i on the host.
  - Generation for VSE Feature Reference
    This reference manual provides z/VSE-specific information about developing and generating EGL programs in the VSE environment.
- Source code analysis with code review
  With code review, you can create configurations of coding rules for EGL source code. You can then run the configurations to check the source code for consistency with the rules.
- Responsive Design Support in RBD
  What is Responsive Design? Responsive design is an approach for creation of web pages that automatically scales its content and elements to match the screen size on which it is viewed. So, instead of designing multiple websites for different devices with variable screen sizes, we can design just one website that scales up or down automatically, to match the device it’s being viewed on.
Samples
Troubleshooting and support
EGL runtime error messages
Reference
Glossary
Using the help
Notices for IBM Rational Business Developer documentation

Program part

A program part defines the central logic in a runtime program.

Program parts have the following characteristics:

Each Program part has a single entry point. That entry point is the required main() function, which represents the logic that runs at program startup and invokes other functions.
A Program can also include other functions and can access functions that are outside of the Program part.
Program parts use stereotypes to specialize code for user interfaces. The BasicProgram is the only stereotype that is part of the core EGL package. A basic program can access databases or files, perform calculations, and use most of the EGL statements. However, a basic program cannot communicate with the user through a browser, 3270 screen, or other interface. Some UI technologies offer additional stereotypes. See the related reference links at the end of this topic for the technologies that you might be using.
Many properties are available at the Program level that affect code behavior. For more information, see Program properties.
You can define either main programs (defined without parameters) or called programs (defined with parameters). For more information, see Main versus called programs.

For more information about Program parts, see Introduction to Program parts.

Syntax

Syntax for the Program part

programName: The name you assigned to this program.
parameter: You can pass parameters, but only to called programs. For more information, see Main versus called programs.
statement: Any EGL statement.

Compatibility

Table 1. Compatibility considerations for the Program part
Platform	Issue
z/OS®	The maximum length of a generated program name is 8 characters.
iSeries® COBOL	The name of a generated program has the following maximum lengths: 7 characters for a main program 8 characters for a called program