The PartData, SupplierData and ShipmentData classes have been removed in this example, and the Part, Supplier and Shipment entity classes are used in their place.

The serial formats are created with the entity classes.

public class SampleDatabase
{
    ...
    public SampleDatabase(String homeDirectory)
        throws DatabaseException, FileNotFoundException
    {
        ...
        secConfig.setKeyCreator(new SupplierByCityKeyCreator(javaCatalog,
                                                             Supplier.class));
        ...
        secConfig.setKeyCreator(new ShipmentByPartKeyCreator(javaCatalog,
                                                             Shipment.class));
        ...
        secConfig.setKeyCreator(new ShipmentBySupplierKeyCreator(javaCatalog,
                                                             Shipment.class));
        ...
    }
} 

The index key creator uses the entity class as well.

public class SampleDatabase
{
    ...

    private static class SupplierByCityKeyCreator
        extends TupleSerialKeyCreator
    {
        private SupplierByCityKeyCreator(ClassCatalog catalog,
                                         Class valueClass)
        {
            super(catalog, valueClass);
        }

        public boolean createSecondaryKey(TupleInput primaryKeyInput,
                                          Object valueInput,
                                          TupleOutput indexKeyOutput)
        {
            Supplier supplier = (Supplier) valueInput;
            String city = supplier.getCity();
            if (city != null) {
                indexKeyOutput.writeString(supplier.getCity());
                return true;
            } else {
                return false;
            }
        }
    }
}