@Override public List<Span> map(List<Span> input) {
      Iterator<Span> i = input.iterator();
      while (i.hasNext()) {
        Span next = i.next();
        if (!next.traceId().equals(traceId)) i.remove();
      }
      return input;
    }
Returns true if any trace clashes on the right-most 16 characters of the trace ID
zipkin/src/main/java/zipkin2/storage/StrictTraceId.java