private List<List<Line>> splitChangeSet(List<Line> remainingMessage) throws BatchDeserializerException { final HeaderField contentTypeField = headers.getHeaderField(HttpHeader.CONTENT_TYPE); final String changeSetBoundary = BatchParserCommon.getBoundary( contentTypeField.getValue(), contentTypeField.getLineNumber()); validateChangeSetBoundary(changeSetBoundary, headers); return BatchParserCommon.splitMessageByBoundary(remainingMessage, changeSetBoundary); }