XML digest in a few lines

com.sun.org.apache.xml.internal.security.c14n.implementations.Canonicalizer11_OmitComments c =
new com.sun.org.apache.xml.internal.security.c14n.implementations.Canonicalizer11_OmitComments();
java.security.MessageDigest md = java.security.MessageDigest.getInstance("SHA1");
md.reset();
md.update(c.engineCanonicalize(xml.getBytes()));
StringBuilder sb = new StringBuilder();
for (byte b : md.digest())
sb.append( String.format("%02x", b) );
digest = sb.toString();