Release 10.1A: OpenEdge Development:
Progress Dynamics Administration

Generating static-4GL equivalents of dynamic objects

The main concept of Progress Dynamics is the use of a Repository to store abstract definitions for executable objects in an application. This abstraction allows the physical implementation of an object to change without requiring changes to and recompilation of the executable objects themselves. Objects are created and rendered using rendering procedures at run time. These rendering procedures retrieve object definitions from the Repository in the form of data and then manipulate that data in order to create the objects and whatever other objects they might specify.

While this dynamic approach to representing and executing the objects for an application has a number of advantages, there are two primary disadvantages when used for an n-tier distributed application:

The application (object) definition must be transported across the network. In order for an object to be rendered, the client rendering program must retrieve the object’s definition from the Repository by making an AppServer request that returns the object definition to the client. There is always some expense incurred in the actual retrieval of the object from the Repository, but the main performance bottleneck occurs in moving the data from the AppServer to the client.

Once on the client, the definition can be cached for future use. However, the client must always get the definition from the AppServer when it first instantiates the object.

Even though an object definition can be cached on the client, the rendering program must always transform this definition at run time in order to render a new instance of the object.

Progress Dynamics allows you to avoid these bottlenecks by generating static-4GL objects from the Repository definitions of dynamic objects.