如前所述,到42岁时,您可以从XML中创建规范XML,这将为您按字母顺序对属性进行排序。
在Java中,我们可以使用Apache的Canonicalizer之类的东西
org.apache.xml.security.c14n.Canonicalizer
这样的事情(假设inXMLDoc中的Document已经是一个DOM):
Document retDoc;
byte[] c14nOutputbytes;
DocumentBuilderFactory factory;
DocumentBuilder parser;
// CANONICALIZE THE ORIGINAL DOM
c14nOutputbytes = Canonicalizer.getInstance(Canonicalizer.ALGO_ID_C14N_WITH_COMMENTS).canonicalizeSubtree(inXMLDoc.getDocumentElement());
// PARSE THE CANONICALIZED BYTES (IF YOU WANT ANOTHER DOM) OR JUST USE THE BYTES
factory = DocumentBuilderFactory.newInstance();
factory.set ... // SETUP THE FACTORY
parser = factory.newDocumentBuilder();
// REPARSE TO GET ANOTHER DOM WITH THE ATTRIBUTES IN ALPHA ORDER
ByteArrayInputStream bais = new ByteArrayInputStream(c14nOutputbytes);
retDoc = parser.parse(bais);
当然,当进行规范化时,其他事情都会更改(它将变成Canonical XMLhttp://en.wikipedia.org/wiki/Canonical_XML),因此,除了属性顺序之外,还需要进行其他更改。