code: protected void addPathValue(Document doc, String fieldName, Object pathString)
     {
  
        doc.add(createFieldWithoutNorms(fieldName, pathString.toString(), PropertyType.PATH));
     }
docs: Adds the path value to the document as the named field. The path
  value is converted to an indexable string value using the name space
  mappings with which this class has been created.
  
  @param doc           The document to which to add the field
  @param fieldName     The name of the field to add
  @param pathString    The value for the field to add to the document.