private void formatTo()

in log4j-1.2-api/src/main/java/org/apache/log4j/layout/Log4j1XmlLayout.java [89:164]
69 lines of code
8 McCabe index (conditional complexity)

    private void formatTo(final LogEvent event, final StringBuilder buf) {
        buf.append("<log4j:event logger=\"");
        buf.append(Transform.escapeHtmlTags(event.getLoggerName()));
        buf.append("\" timestamp=\"");
        buf.append(event.getTimeMillis());
        buf.append("\" level=\"");
        buf.append(Transform.escapeHtmlTags(String.valueOf(event.getLevel())));
        buf.append("\" thread=\"");
        buf.append(Transform.escapeHtmlTags(event.getThreadName()));
        buf.append("\">");
        buf.append(EOL);

        buf.append("<log4j:message><![CDATA[");
        // Append the rendered message. Also make sure to escape any existing CDATA sections.
        Transform.appendEscapingCData(buf, event.getMessage().getFormattedMessage());
        buf.append("]]></log4j:message>");
        buf.append(EOL);

        final List<String> ndc = event.getContextStack().asList();
        if (!ndc.isEmpty()) {
            buf.append("<log4j:NDC><![CDATA[");
            Transform.appendEscapingCData(buf, Strings.join(ndc, ' '));
            buf.append("]]></log4j:NDC>");
            buf.append(EOL);
        }

        @SuppressWarnings("ThrowableResultOfMethodCallIgnored")
        final Throwable thrown = event.getThrown();
        if (thrown != null) {
            buf.append("<log4j:throwable><![CDATA[");
            final StringWriter w = new StringWriter();
            thrown.printStackTrace(new PrintWriter(w));
            Transform.appendEscapingCData(buf, w.toString());
            buf.append("]]></log4j:throwable>");
            buf.append(EOL);
        }

        if (locationInfo) {
            final StackTraceElement source = event.getSource();
            if (source != null) {
                buf.append("<log4j:locationInfo class=\"");
                buf.append(Transform.escapeHtmlTags(source.getClassName()));
                buf.append("\" method=\"");
                buf.append(Transform.escapeHtmlTags(source.getMethodName()));
                buf.append("\" file=\"");
                buf.append(Transform.escapeHtmlTags(source.getFileName()));
                buf.append("\" line=\"");
                buf.append(source.getLineNumber());
                buf.append("\"/>");
                buf.append(EOL);
            }
        }

        if (properties) {
            final ReadOnlyStringMap contextMap = event.getContextData();
            if (!contextMap.isEmpty()) {
                buf.append("<log4j:properties>\r\n");
                contextMap.forEach((key, val) -> {
                    if (val != null) {
                        buf.append("<log4j:data name=\"");
                        buf.append(Transform.escapeHtmlTags(key));
                        buf.append("\" value=\"");
                        buf.append(Transform.escapeHtmlTags(Objects.toString(val, null)));
                        buf.append("\"/>");
                        buf.append(EOL);
                    }
                });
                buf.append("</log4j:properties>");
                buf.append(EOL);
            }
        }

        buf.append("</log4j:event>");
        buf.append(EOL);
        buf.append(EOL);
    }