Ronald Bourret

Consulting, writing, and research in XML and databases

XML-DBMS: Known bugs

Values are placed in the wrong elements / attributes when retrieving data from a result set in version 2.0.

The version of Transfer in the alpha 3 release (incorrectly) does not call org.xmlmiddleware.xmldbms.maps.utils.MetadataInitializer, which is used to match result set columns to mapping information. To fix this, you need to make the changes to org.xmlmiddleware.xmldbms.tools.Transfer listed below.

• Add the following import:

     import org.xmlmiddleware.xmldbms.maps.utils.*;
  

• Modify the method private Document retrieveDocumentInternal(Properties configProps, String mapFilename, Properties selects, String filterFilename, Hashtable params) so that it calls initTableMetadata:

     private Document retrieveDocumentInternal(Properties configProps,
              String mapFilename, Properties selects, String filterFilename,
              Hashtable params)
        throws XMLMiddlewareException, SQLException
     {
        ...
        resultSets = createResultSets(selects);
        transferInfo = createTransferInfo(map);
        filterSet = createFilterSet(map, filterFilename,
                                    (validate.indexOf(XMLDBMSProps.FILTERTOKEN) != -1));
  
        // New line of code:
        initTableMetadata(map, resultSets, filterSet);
  
        // Configure the DBMSToDOM object
        ...
     }
  

• Add the following method:

     private void initTableMetadata(XMLDBMSMap map, Hashtable resultSets, FilterSet filterSet)
        throws XMLMiddlewareException
     {
        MetadataInitializer initializer;
        Vector filters;
        Object o;
        ResultSetFilter rsFilter;
        String rsName;
        ResultSet rs;
        Table table;
  
        // Get a new MetadataInitializer.
  
        initializer = new MetadataInitializer(map);
  
        // Get the Vector of RootFilters and ResultSetFilters. Loop through the
        // filters and, for each ResultSetFilter that is found, use the result set
        // metadata to initialize the corresponding table metadata. Note that
        // ResultSetFilters associate result set names with table names.
  
        filters = filterSet.getFilters();
        for (int i = 0; i < filters.size(); i++)
        {
           // Get the next object and process it if it is a ResultSetFilter.
  
           o = filters.elementAt(i);
           if (o instanceof ResultSetFilter)
           {
              rsFilter = (ResultSetFilter)o;
  
              // Get the name of the result set specified in the filter and
              // get the corresponding ResultSet object.
  
              rsName = rsFilter.getResultSetName();
              rs = (ResultSet)resultSets.get(rsName);
              if (rs == null)
                 throw new XMLMiddlewareException("Filter document specifies a " +
                    "result set with the name " + rsName + ". No result set with " +
                    "this name was specified in the properties passed to Transfer.");
  
              // Get the name of the table specified in the filter; this is the
              // name of the table in the map that maps the result set. Get the
              // corresponding Table object.
  
              table = map.getTable(rsFilter.getDatabaseName(),
              rsFilter.getCatalogName(),
              rsFilter.getSchemaName(),
              rsFilter.getTableName());
              if (table == null)
                 throw new XMLMiddlewareException("Table specified in " +
                    "filter document but not found in map: " +
                    Table.getUniversalName(rsFilter.getDatabaseName(),
                       rsFilter.getCatalogName(), rsFilter.getSchemaName(),
                       rsFilter.getTableName()));
  
              // Initialize the metadata for the columns in the table from
              // the result set metadata.
  
              initializer.initializeMetadata(table, rs);
           }
        }
     }