if (key == null || Utilities.isEmptyString(value)) {
return;
}
ShorthandPropertyExpander spe = key.getExpander();
if (spe != null) {
spe.parseAndExpandProperty(attr, value);
} else {
Object cssValue = key.getConverter().toCSS(value);
if (cssValue != null) {
attr.addAttribute(key, cssValue);
}