in geronimo-opentracing-common/src/main/java/org/apache/geronimo/microprofile/opentracing/common/microprofile/zipkin/ZipkinHttp.java [153:161]
public void onEvent(final ZipkinSpan zipkinSpan) {
if (collector != null) {
if (spans == null) {
doSend(singletonList(zipkinSpan));
} else {
spans.add(zipkinSpan);
}
}
}