private void validateKey(String key)
{
if (key == null || key.length() == 0)
throw new IllegalArgumentException("null or empty key");
CompositeMetaType metaType = getMetaType();
if (metaType.containsKey(key) == false)
throw new IllegalArgumentException("no such item name " + key + " for composite type " + metaType);
}
/**
* Construct Composite Value