The interface is the screen display that you use to interact with
an application. You can use EGL to create different kinds of application
interfaces, including:
- Javascript web pages
- Text-based console screens such as those on a mainframe
- Rich client displays that match the look and feel of the local
operating system
The type of EGL application that you create is decided not by the
type of project that you create in the workbench, but by the type
of EGL artifacts that you use and the type of interface that you create
for the application. Whatever the type of the application, the EGL
projects, files, and code are organized in a similar way.
You can create an application that has the characteristics of more
than one of these applications.
If your EGL installation is configured to allow all of them, EGL
can create the following types of applications:
- Basic application
- A basic application consists of one or more standalone EGL programs.
Basic EGL applications provide batch processing or serve as the business
logic behind one or more EGL applications with interfaces.
- Web application
- A web application consists of one or more web pages. You can use web transactions, which are simple web-based
programs migrated from VisualAge® Generator.
- Rich UI application
- A Rich UI application consists of one or more web pages that use
client-side JavaScript for
increased flexibility and responsiveness.
- Text user interface application (Text UI)
- A text UI application presents a text-based user interface such
as that of a 5250 or 3270 terminal.
- Service-oriented application
- A service-oriented application does not have its own user interface.
Instead, each service in that application is designed to be invoked
by other code, including by other services. Like an EGL library, a
service includes a list of functions that requesters can access. Services
are stateless, which means that they treat each interaction
with a requester as new and unique. Every time a service runs, it
is as if it is running for the first time.
- Report
- A report application produces printed output, such as forms or
charts.
Regardless of the type of application you work with, the structure
of the EGL projects, packages, and files in your workspace is essentially
the same: you write similar EGL code in similar EGL logic components.
From a programming standpoint, the major difference between these
types of applications is the type of interface that the application
uses.