qname

In XML documents conforming to this specification, some names (constructs corresponding to the nonterminal Name) MUST be given as qualified names，defined as follows:

Qualified Name

[7]	QName	::=	PrefixedName
			| UnprefixedName
[8]	PrefixedName	::=	Prefix ':' LocalPart
[9]	UnprefixedName	::=	LocalPart
[10]	Prefix	::=	NCName
[11]	LocalPart	::=	NCName

也就是说 QName有两种：

一种是带前缀的，<perfix:localpart>...</perfix:localpart> 

另一种是不带前缀的，<localpart></localpart>

在java中QName有三个主要属性

    /**
     * <p>Namespace URI of this <code>QName</code>.</p>
     */

    private final String namespaceURI;


    /**
     * <p>local part of this <code>QName</code>.</p>
     */
    private final String localPart;


    /**
     * <p>prefix of this <code>QName</code>.</p>
     */
    private final String prefix;

对于一个QName  <ns:locala xmlns:ns="http://sdjfhs.fkslj.cn"><ns:locala>

namespaceURI = http://sdjfhs.fkslj.cn

localPart = locala

prefix = ns