stdXmlStreamWriter.writeCharacters("abcdcba".toCharArray(), 3, 1);
xmlSecurityStreamWriter.writeEntityRef("x0");
stdXmlStreamWriter.writeEntityRef("x0");
xmlSecurityStreamWriter.writeEndElement();
stdXmlStreamWriter.writeEndElement();
xmlSecurityStreamWriter.writeProcessingInstruction("PI");
stdXmlStreamWriter.writeProcessingInstruction("PI");