public synchronized String format()

in src/main/java/org/apache/log4j/xml/XSLTLayout.java [247:394]
111 lines of code
21 McCabe index (conditional complexity)

    public synchronized String format(final LoggingEvent event) {
      if (!activated) {
          activateOptions();
      }
      if (templates != null && encoding != null) {
          outputStream.reset();

          try {
            TransformerHandler transformer =
                      transformerFactory.newTransformerHandler(templates);

            transformer.setResult(new StreamResult(outputStream));
            transformer.startDocument();

            //
            //   event element
            //
            AttributesImpl attrs = new AttributesImpl();
            attrs.addAttribute(null, "logger", "logger",
                    "CDATA", event.getLoggerName());
            attrs.addAttribute(null, "timestamp", "timestamp",
                    "CDATA", Long.toString(event.timeStamp));
            attrs.addAttribute(null, "level", "level",
                    "CDATA", event.getLevel().toString());
            attrs.addAttribute(null, "thread", "thread",
                    "CDATA", event.getThreadName());
            StringBuffer buf = new StringBuffer();
            utcDateFormat.format(event.timeStamp, buf);
            attrs.addAttribute(null, "time", "time", "CDATA", buf.toString());


            transformer.startElement(LOG4J_NS, "event", "event", attrs);
            attrs.clear();

            //
            //   message element
            //
            transformer.startElement(LOG4J_NS, "message", "message", attrs);
            String msg = event.getRenderedMessage();
            if (msg != null && msg.length() > 0) {
                transformer.characters(msg.toCharArray(), 0, msg.length());
            }
            transformer.endElement(LOG4J_NS, "message", "message");

            //
            //    NDC element
            //
            String ndc = event.getNDC();
            if (ndc != null) {
                transformer.startElement(LOG4J_NS, "NDC", "NDC", attrs);
                char[] ndcChars = ndc.toCharArray();
                transformer.characters(ndcChars, 0, ndcChars.length);
                transformer.endElement(LOG4J_NS, "NDC", "NDC");
            }

            //
            //    throwable element unless suppressed
            //
              if (!ignoresThrowable) {
                String[] s = event.getThrowableStrRep();
                if (s != null) {
                    transformer.startElement(LOG4J_NS, "throwable",
                            "throwable", attrs);
                    char[] nl = new char[] { '\n' };
                    for (int i = 0; i < s.length; i++) {
                        char[] line = s[i].toCharArray();
                        transformer.characters(line, 0, line.length);
                        transformer.characters(nl, 0, nl.length);
                    }
                    transformer.endElement(LOG4J_NS, "throwable", "throwable");
                }
              }

              //
              //     location info unless suppressed
              //
              //
              if (locationInfo) {
                LocationInfo locationInfo = event.getLocationInformation();
                attrs.addAttribute(null, "class", "class", "CDATA",
                        locationInfo.getClassName());
                attrs.addAttribute(null, "method", "method", "CDATA",
                          locationInfo.getMethodName());
                attrs.addAttribute(null, "file", "file", "CDATA",
                            locationInfo.getFileName());
                attrs.addAttribute(null, "line", "line", "CDATA",
                            locationInfo.getLineNumber());
                transformer.startElement(LOG4J_NS, "locationInfo",
                        "locationInfo", attrs);
                transformer.endElement(LOG4J_NS, "locationInfo",
                        "locationInfo");
              }

              if (properties) {
                //
                //    write MDC contents out as properties element
                //
                Set mdcKeySet = MDCKeySetExtractor.INSTANCE.getPropertyKeySet(event);

                if ((mdcKeySet != null) && (mdcKeySet.size() > 0)) {
                    attrs.clear();
                    transformer.startElement(LOG4J_NS,
                            "properties", "properties", attrs);
                    Object[] keys = mdcKeySet.toArray();
                    Arrays.sort(keys);
                    for (int i = 0; i < keys.length; i++) {
                        String key = keys[i].toString();
                        Object val = event.getMDC(key);
                        attrs.clear();
                        attrs.addAttribute(null, "name", "name", "CDATA", key);
                        attrs.addAttribute(null, "value", "value",
                                "CDATA", val.toString());
                        transformer.startElement(LOG4J_NS,
                                "data", "data", attrs);
                        transformer.endElement(LOG4J_NS, "data", "data");
                    }
                }
              }


            transformer.endElement(LOG4J_NS, "event", "event");
            transformer.endDocument();

            String body = encoding.decode(
                    ByteBuffer.wrap(outputStream.toByteArray())).toString();
            outputStream.reset();
            //
            //   must remove XML declaration since it may
            //      result in erroneous encoding info
            //      if written by FileAppender in a different encoding
            if (body.startsWith("<?xml ")) {
                int endDecl = body.indexOf("?>");
                if (endDecl != -1) {
                    for(endDecl += 2; 
					     endDecl < body.length() &&
						 (body.charAt(endDecl) == '\n' || body.charAt(endDecl) == '\r'); 
						 endDecl++);
                    return body.substring(endDecl);
                }
            }
            return body;
          } catch (Exception ex) {
              LogLog.error("Error during transformation", ex);
              return ex.toString();
          }
      }
      return "No valid transform or encoding specified.";
    }