SpanHandler end callback returned false still flushed to Zipkin / Jaeger

[DarthJonathan]

Describe the Bug

I just realized either I'm implementing it wrongly or not because in the example of SpanHandler

tracingBuilder.addSpanHandler(new SpanHandler() { @OverRide public boolean end(TraceContext context, MutableSpan span, Cause cause) { return !"comment".equals(span.name()); } });

If returned false it should not be reported in Zipkin / Jaeger right.

does not work, not dropping the span and when I debug I saw
spanHandler.end(last.handlerContext, last.span, Cause.FINISHED);

It is not being handled just flushed, was there any changes in the library and this documentation is outdated? Thanks

Steps to Reproduce

Steps to reproduce the behavior:

Create a bean of SpanHandler or implement TracingCustomizer for TracingFactoryBean.

Make the end callback returned false.

Check in Zipkin / Jaeger collector if the span still being collected.

Expected Behaviour

Suggest what you think correct behaviour should be. Note, it may be solved differently depending on the problem.

Based on the example the span should be dropped / abandoned.

[RossZhang-cpu]

Hi Jonathan, It seems work fine during my test, Not sure if is the different implemtation so I post here for reference.
public class CustomSpanHandler extends SpanHandler {
@OverRide
public boolean end(TraceContext context, MutableSpan span, Cause cause) {
return !"comment".equals(span.name());
}
}

@bean
Tracing tracing(@value("${brave.localServiceName:${spring.application.name}}") String serviceName,
SpanHandler zipkinSpanHandler){
return Tracing.newBuilder()
.currentTraceContext(ThreadLocalCurrentTraceContext.create())
.localServiceName(serviceName)
.addSpanHandler(zipkinSpanHandler)
.build();
}

After that I checked in Zipkin UI site, this span don't display there. If anything wrong， please corret it.