How to produce XML signature with no whitespaces and line-breaks in Java?

Question

I work with the brazilian \"Nota Fiscal Eletronica\" project, in which they define a standart way to sign XML documents.

Recently, they started to require that there

Answer 1

We just need to set the "true" value to the "ignoreLineBreaks" parameter, cause' the default value is false and this allows to the signature API to add LineBreaks

here is the code to avoid or remove LineBreaks

Field f = XMLUtils.class.getDeclaredField("ignoreLineBreaks");
f.setAccessible(true);
f.set(null, Boolean.TRUE);

then, we'll can make sure that the new value is true with the next code line

System.err.println(XMLUtils.ignoreLineBreaks());

I had the same problem and this worked for me.