Structuring OO applications

You can structure applications that use object-oriented COBOL syntax in one of three ways.

About this task

An OO application can begin with:

  • A COBOL program, which can have any name.

    Under z/OS® UNIX, you can run the application by specifying the name of the linked module (which should match the program name) at the command prompt. You can also bind the program as a module in a PDSE and run it in JCL using the EXEC PGM statement.

  • A Java™ class definition that contains a method called main. Declare main as public, static, and void, with a single parameter of type String[].

    You can run the application with the java command, specifying the name of the class that contains main, and zero or more strings as command-line arguments.

  • A COBOL class definition that contains a factory method called main. Declare main with no RETURNING phrase and a single USING parameter, an object reference to a class that is an array with elements of type java.lang.String. (Thus main is in effect public, static, and void, with a single parameter of type String[].)

    You can run the application with the java command, specifying the name of the class that contains main, and zero or more strings as command-line arguments.

    Structure an OO application this way if you want to:
    • Run the application by using the java command.
    • Run the application in an environment where applications must start with the main method of a Java class (such as a Java dependent region).
    • Follow standard Java programming practice.

    Examples: COBOL applications that run using the java command