}
public Map<String, String> getMDCPropertyMap() {
// populate mdcPropertyMap if null
if (mdcPropertyMap == null) {
MDCAdapter mdc = MDC.getMDCAdapter();
if (mdc instanceof LogbackMDCAdapter)
mdcPropertyMap = ((LogbackMDCAdapter) mdc).getPropertyMap();
else
mdcPropertyMap = mdc.getCopyOfContextMap();
}
// mdcPropertyMap still null, use CACHED_NULL_MAP
if (mdcPropertyMap == null)
mdcPropertyMap = CACHED_NULL_MAP;