When starting from a SOAPMessage, the easiest way is to use the writeTo
method :
ByteArrayOutputStream stream = new ByteArrayOutputStream();
soapMessage.writeTo(stream);
String message = new String(stream.toByteArray(), "utf-8")
(Above, I assume your SAAJ implementation will use UTF-8, you'd probably want to check).
If starting from a SOAPBody, then you probably should use XML APIs, seeing SOAPBody is a org.w3.dom.Element, the easiest way would probably be using TrAX :
SOAPBody element = ... // Whatever
DOMSource source = new DOMSource(element);
StringWriter stringResult = new StringWriter();
TransformerFactory.newInstance().newTransformer().transform(source, new StreamResult(stringResult));
String message = stringResult.toString();
(Sorry I do not have my IDE right here, can not check if this compiles, but that should be pretty close).
Please note : A serialized SOAPMessage may not be raw XML : it might be a MIME structure : if the SOAPMessage actually uses SwA (SOAP With Attachment) or MTOM. However, SOAPBody is definitely pure XML.
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