An XML catalog describes the mapping between external entity references and locally cached equivalents for an XML external resource.

You can create an XML catalog file using the application Protégé[1]. The version of Protégé used in these instructions is version 4.3.0. 


To create an XML catalog file for a locally cached set of external ontologies


  1. Open Protégé.
  2. Select File > New.

    Creating an OWL ontology in Protégé application.
  3. Select Save as.

    Saving an OWL ontology in Protégé.
  4. Navigate to a folder location.
  5. Name the empty ontology.
  6. Click Save.

    Saving the OWL ontology file to a selected location.
  7. Click File > Open.

    Opening the OWL ontology in Protégé.
  8. Click Yes.

    Opening the OWL ontology in the current window option.
  9. Select the newly created ontology.
  10. Click Open.
    Selecting an OWL ontology to open. 

To create an XML catalog file for the desired locally cached set of external ontologies:


  1. Click File > Edit active ontology library.

    Creating an XML catalog file in Protégé.
  2. Click on the Folder Repository for the empty ontology.
  3. Click Delete (-). 

    Deleting a folder repository.
  4. Click Add (+).

    Adding a folder repository.
  5. Click on Folder Repository.
  6. Select Recursively searchsubdirectories.

    Locating for a folder repository.
  7. Select the desired folder.
  8. Click Open.
    Selecting a folder repository.
  9. Click OK.
    The new folder repository is added.



[1] Protégé is a free, open-source ontology editor, and a framework for building knowledge management systems.

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