LabelLocator2 implementation?

public class FooDBLocator extends org.zkoss.util.resource.LabelLocator2 {
    private String _field;
    public FooDBLocator(String field) {
        _field = field;
    }
    public InputStream locate(Locale locale) {
        InputStream is = ... //load the properties from, say, database
        return is;
    }
    public String getCharset() {
        return "UTF-8"; //depending the encoding you use
    }
}