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.
Accessing data in EGL
Whenever you access a data store in EGL, the data goes into a record.
iSeries® object access
EGL provides a library and Record definitions to communicate with data queues and data areas on the iSeries®.
iSeries® function calls
iSeries® functions provide access to data queues and data areas.
clearQueue()

Overview
Getting started
Installing
Upgrading and migrating
EGL Code Accelerator for IBD
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 IBM Business Developer documentation.
  - 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
    - 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.
      - resourceAssociation variable for file I/O
        When your program uses a record in an I/O operation, EGL assumes that the record-specific recordName.resourceAssociation variable contains the name of the physical file that holds the record (if that variable supports the particular type of file).
      - Logical unit of work
      - Data access statements
        EGL data access statements perform the essential create, read, update, and delete (CRUD) functions for a data source.
      - execute considerations for CICS®
        In the context of CICS®, the EGL execute statement is typically used to carry out a native EXEC CICS statement with dynamic elements. Local EGL variables in the same program may be referenced in the statement, or labels within the same function. EGL will generate an EXEC CICS statement containing the provided text, resolved variable and label names and imbed this into the application program.
      - execute Considerations for COBOL
        In the context of COBOL, the EGL execute statement is typically used to carry out a native COBOL statement with dynamic elements. Local EGL variables in the same program may be referenced in the statement, or labels within the same function. EGL will generate a COBOL statement containing the provided text, resolved variable and label names and embed this into the application program.
      - Data access technologies
      - SQL data access
        EGL supports relational database access through SQL.
      - Data access using PSBs and PCBs
        Use program specification blocks (PSBs) and program communication blocks (PCBs) to describe the logical structures in a program you generate for COBOL.
      - DL/I database support
        EGL supports DL/I (Data Language/I), a hierarchical database manager for COBOL environments.
      - File I/O
        You can use EGL to read from or write to files directly, without using a database manager.
      - GSAM and IMS™ message queue access
        GSAM and IMS™ message queues are two examples of serial file access through EGL.
      - WebSphere® MQ message queue access
        EGL supports access of WebSphere® MQ (formerly MQSeries®) message queues on any of the target platforms.
      - iSeries® object access
        EGL provides a library and Record definitions to communicate with data queues and data areas on the iSeries®.
        iSeries® Record definitions
        EGL provides Record definitions that correspond to objects in the iSeries® environment.
        iSeries® function calls
        iSeries® functions provide access to data queues and data areas.
        addElement()
        The addElement() function adds data to a specified iSeries® data queue.
        browseNextElement()
        clearQueue()
        getDataArea()
        getNextElement()
        updateDataArea()
    - 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.
  - IBM 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 IBD
  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.
- Containerizing an EGL RUI Application
Samples
Troubleshooting and support
EGL runtime error messages
Reference
Glossary
Using the help
Notices for IBM Business Developer documentation

clearQueue()

The clearQueue() function removes all data from a specified iSeries® data queue.

Syntax

  iplatformLib.clearQueue(
    dataQueueDef DataQueueDefinition inOut )

platform: The string "Cobol" or "Java™", depending on the platform for which you are generating the program.
dataQueueDef: A variable based on the DataQueueDefinition Record (see iSeries Record definitions).