public java.net.URL getURL(int columnIndex) throws SQLException {
        throw new UnsupportedOperationException();
    }
Retrieves the value of the designated column in this
<code>CachedRowSetImpl</code> object as a <code>java.net.URL</code> object
in the Java programming language.

@return a java.net.URL object containing the resource reference described by
the URL
@throws SQLException if (1) the given column index is out of bounds,
(2) the cursor is not on one of this rowset's rows or its
insert row, or (3) the designated column does not store an
SQL <code>DATALINK</code> value.
@see #getURL(String)
src/main/java/org/replicadb/rowset/sun/rowset/internal/SyncResolverImpl.java