The aim of this diploma thesis is to create, for a particular company, an innovative approach for the ongoing process of planning and verification of JCL scripts integrated in the system mainframe. These processes are currently inefficient and must be improved. During the planning process of JCL scripts an internal application will be created that increases team effectiveness and simplifies the preparation of procurement reports. With the internal application the company will also need a system upgrade of the mainframe Control-M from BMC software company, which will significantly improve the process of verifying JCL scripts. This thesis includes a functional application with the source code.

In the thesis I am presenting a plugin in the integrated development environment Eclipse. Plugin is designed to support writing code in JCL programming language. In the first part of the thesis I am focusing on the mainframe platform from the IBM corporation on which the JCL language is used. I also focus on the z/OS operating system and it`s components required for adequate runtime environment for JCL language. In the next section I am discussing the Eclipse environment which is used as runtime platform for the plugin. As a base for the plugin is used an Xtext framework. The framework is specifically designed for development of custom domain specific languages.