XML Canonicalizer Problem

Question

I'm using the package org.apache.xml.security.c14nfor the canonicalization of XMLs. I use the following code:

private String CanonicalizeXML(String XML) throws InvalidCanonicalizerException, CanonicalizationException, ParserConfigurationException, IOException, SAXException {

    Canonicalizer canon = Canonicalizer.getInstance(Canonicalizer.ALGO_ID_C14N_OMIT_COMMENTS);
    return new String(canon.canonicalize(XML.getBytes()));
}

However, it doesn't seem to work as I expected, since it doesn't delete any non-necessary white spaces between elements. Do I do something wrong?

Thanks,

Ivan

score 2 · Accepted Answer · answered Feb 28 '11 at 12:04

2

I think it may be your expectation which is incorrect:

You don't say which version of XML Canonicalization, but both 1.0 and 1.1 say:

All whitespace in character content is retained (excluding characters removed during line feed normalization)

answered Feb 28 '11 at 12:04

Chris Dickson

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I want any version which would remove the spaces. How to achieve that? – Ivan Feb 28 '11 at 12:12

score 1 · Answer 2 · answered Feb 28 '11 at 11:46

1

Is your xml document referencing a dtd or schema? Without one of those the parser has no way to know which whitespace is significant and so it has to preservere it.

answered Feb 28 '11 at 11:46

Jörn Horstmann

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Hmm... That explains a lot. I don't have a schema, but I will obviously have to create one. Or is there another way how to force it to delete whitespaces as they are irrelevant? Something like a very simple schema or something. – Ivan Feb 28 '11 at 11:56

score 0 · Answer 3 · answered Jul 05 '12 at 15:44

The org.apache.xml.security.c14n does not remove whitespaces.

I resolved by setting setIgnoringBoundaryWhitespace = true on my SAXBuilder:

SAXBuilder builder = new SAXBuilder ();
builder.setIgnoringBoundaryWhitespace(true);
org.jdom2.Document doc = builder.build(is);
DOMOutputter out = new DOMOutputter();
Document docW3 = out.output(doc);

XML Canonicalizer Problem

3 Answers3