Chapter 2: Using Mainframe Express

This chapter briefly describes differences between how you use COBOL Workbench and how you use Mainframe Express.

In Workbench you use Animator V2 for editing, compiling and debugging, and you use Organizer or Advanced Organizer to group files for specific projects or applications to enable batch compilation or other tasks to be performed on those files. In Mainframe Express, the Integrated Development Environment (IDE) merges these functions (and more) within one interface. Its facilities for setting breakpoints and interrogating data while debugging are more advanced, as are the Build functions which make possible intelligent recompilation of only those files affected by a change.

Central to the way you use Mainframe Express are projects. Projects in Mainframe Express are different from those in Workbench - read about them in your User's Guide for details. Briefly, a project defines all the files in your application, how they are related and how they should be compiled. When creating an application, the first thing you do is create its project. You keep it loaded all the time you are working on the application.

This is useful in several ways. For example, it ensures the correct folder - where you create all the files for your application - is kept open. Also, you can load source files quickly by double-clicking their names in the project view. Creating the project first helps you design your application, and you can easily add or remove files if you decide to change anything.

You can compile the entire application by a few clicks of the mouse. Source programs are automatically compiled in the right order to take care of dependencies - for example BMS compilations are done before COBOL compilations, because the copybooks produced by the former are needed by the latter. The whole process is guided by the project, which specifies the source files and settings. This is known as building the project (unlike in Workbench, where building means building .int/.gnt files into a library).

In Workbench, source-level debugging is known as animating. In Mainframe Express, it is generally referred to simply as debugging.

Because Mainframe Express is intended for developing and testing applications that will be run on the mainframe, not on the PC, Mainframe Express does not produce .obj and .exe executable files. You run your application within the IDE. All running is controlled by the debugger (the Animator). To do a normal non-animated run you use the Run function on the Debug menu - in effect, using the Animator but zooming the whole program.

In Mainframe Express, you don't need to be aware of the format of compiled code. There is an option to create optimized code, which corresponds to compiling COBOL source to generated (.gnt) code, but using this option makes little difference to the features available. Unlike Workbench, where you had to enable additional options to animate .gnt code, Mainframe Express can simply debug a program whether or not you have optimized it, dependent only on the Create debug information option.

In Workbench, you set options mainly by the use of directives and environment variables. In Mainframe Express, these have been largely replaced by settings on dialog boxes invoked by two functions on the Project menu. As a general guide, you set options connected with the behavior of compilers and preprocessors via the Build Settings function, while for run-time options and project-level settings you use Project Settings. The chapters Environment Variables and COBOL Compiler Directives describe in detail where to find individual options.

You may have been using the character-mode tools Animator and Editor in Workbench. These are not in Mainframe Express. Like Animator V2, the IDE provides most of what these two tools do, and more. The graphical interface gives multiple windows that you can easily rearrange and resize, much more powerful data monitoring, and close integration between editing and debugging so that you can correct and recompile code while debugging.