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Introduction to COBOL modernization

This page will guide you through the creation of a new COBOL modernization project.
Creating a Blu Age modernization project will transform your legacy code into a language understandable by any developer. It will also enhance your team productivity by :

COBOL Project Creation

To create a new BluAge Cobol Modernization project, use the following steps :

  1. Right-click on the Explorer view;
  2. Select the menu entry New -> Other;


  3. Select COBOL Reverse Project in the BLU AGE Reverse Modeling -> Cobol Project folder;


  4. Enter a project name and click Next;


  5. The following screen will appear :


    1. First step is to find the location of your COBOL legacy inputs. They can be imported either from a folder or from an archive file. Select the appropriate format as shown in (1) and then browse the location accordingly;
    2. You can then select the COBOL type of your legacy inputs between ANSI format and TANDEM format, as shown in (2);
    3. The checkbox shown in (3) allows, when enabled, to generate useful metrics regarding your COBOL legacy inputs;
    4. You can then choose the importing behavior regarding your COBOL legacy inputs file extensions, as shown in (4) :
      • None : Your file extensions will be let untouched.
      • Rename : Your file extensions will be removed and appropriate ones will be appended depending on the content of each file.
      • Append : Your file extensions will be let untouched and appropriate ones will be appended depending on the content of each file.

        These last two options are useful when your file extensions don't match the ones supported by BluAge Reverse tool, which are cblmf, cpy and bms.
        If your COBOL legacy files are in that case (for instance, when your COBOL files have the cbl extension), you may want to select one of them.
        To select the right one, keep an eye on the COBOL include statements in your files. If the file extension appears in these statements, then choose the Append option. Otherwise, choose the Rename option.
        - INCLUDE 'example' -> Rename option
        - INCLUDE 'example.cpy' -> Append option

    5. Finally, you can specify the behavior regarding your copybooks. Physical inlining will copy/paste the content of each copybook on each COBOL file referencing it, such as the final text file will be modified. If you don't want your COBOL files to be modified, you can deactivate this. Copybooks will only be logically inlined, such as the text won't be modified but the COBOL editor will inline your copybooks on-the-fly. We strongly recommend that you keep this checkbox checked, logical inlining being only used for compatibility purpose. For more information about copybooks management, please refer to the Copybooks Management page.
  6. When you import configuration is correct, you can click on Finish.

The extraction process will start. It might take several minutes if the number of programs imported and/or their size is significant.

COBOL Project Structure

Once the extraction process has finished, a new project is added to the package explorer view. Then, if not already done, you may want to build it.

  • All copybooks will then be injected in the cblmf files for all INCLUDE statements;
  • Your files will be parsed against the BluAge COBOL parser and parsing issues will be displayed in the Problems view of the IDE.


  1. The cobol folder contains your COBOL legacy inputs;
  2. The mockup folder contains the extracted UI elements you will be likely to generate during the modernization process.

TODO : This section is incomplete and should be enhanced.

Knowledge Base Creation

In order to begin the modernization process, a BluAge Knowledge Base project must be present in the workspace. It will help you sharing many information on your modernization project such as annotations on your COBOL files, artifacts, scripts,...

For more information about the creation and usage of a BluAge Knowledge Base project, please refer to the Knowledge Base project page.