QName derived from parsing the formatted String.
If the String is null or does not conform to QName.toString() formatting, an IllegalArgumentException is thrown.
The StringMUST be in the form returned by QName.toString().
The commonly accepted way of representing a QName as a String was defined by James Clark. Although this is not a standard specification, it is in common use, e.g. Transformer.setParameter(String name, Object value) . This implementation parses a String formatted as: "{" + Namespace URI + "}" + local part. If the Namespace URI .equals(XMLConstants.NULL_NS_URI), only the local part should be provided.
The prefix value CANNOT be represented in the String and will be set to XMLConstants.DEFAULT_NS_PREFIX.
This method does not do full validation of the resulting QName.
The Namespace URI is not validated as a URI reference . The local part is not validated as a NCName as specified in Namespaces in XML .