### Question:
TraceProtoUtils { public static ByteString toProtoSpanId(String spanId) { return ByteString.copyFrom(SpanId.bytesFromHex(spanId, 0)); } private  TraceProtoUtils(); static ByteString toProtoSpanId(String spanId); static ByteString toProtoTraceId(String traceId); static TraceConfig traceConfigFromProto(
      io.opentelemetry.proto.trace.v1.TraceConfig traceConfigProto);  }### Answer:
@Test void toProtoSpanId() { ByteString expected = ByteString.copyFrom(SPAN_ID_BYTES); assertThat(TraceProtoUtils.toProtoSpanId(SpanId.bytesToHex(SPAN_ID_BYTES))).isEqualTo(expected); }