@Override public <C> BraveSpanContext extract(Format<C> format, C carrier) {
    Extractor<TextMap> extractor = formatToExtractor.get(format);
    if (extractor == null) {
      throw new UnsupportedOperationException(format + " not in " + formatToExtractor.keySet());
    }
    TraceContextOrSamplingFlags extractionResult = extractor.extract((TextMap) carrier);
    return BraveSpanContext.create(extractionResult);
  }
@ Override public < C > BraveSpanContext extract ( Format < C > format , C carrier ) { Extractor < TextMap > extractor = formatToExtractor . get ( format ) ; if ( extractor == null ) { throw new UnsupportedOperationException ( format + " not in " + formatToExtractor . keySet ( ) ) ; } TraceContextOrSamplingFlags extractionResult = extractor . extract ( ( TextMap ) carrier ) ; return BraveSpanContext . create ( extractionResult ) ; }
Extracts the underlying context using B3 encoding by default. Null is returned when there is no
encoded context in the carrier, or upon error extracting it.