How to create a recording Span given a parent Span's traceId and spanId?

The data flow I am trying to instrument has a variety of in-band mechanisms for propagating context (SQS, Kinesis messages, entries written in a DB, etc.) In the process of manually instrumenting some components, I need to extract the context and create recording Spans which will reflect the work being done by those components. I have tried a couple of versions of this:

Span parentSpan = Span.wrap(SpanContext.createFromRemoteParent(traceId,
                                                               parentSpanId,
                                                               TraceFlags.getDefault(), 
                                                               TraceState.getDefault()));

Context propagatedContext = Context.current().with(parentSpan);

Span span = tracer.spanBuilder("please-export-me")
                  .setParent(propagatedContext)
                  .startSpan();

However, the resulting span is of type PropagatedSpan and hence isRecording is false.

What is the correct way to solve this use case?

Figured this out! The problem in the above code is in the TraceFlags. TraceFlags.getDefault() returns 0x00, which marks it as not sampled. We need 0x01 - which is returned by TraceFlags.getSampled(). The code below works, with span now being the SdkSpan implementation, which is exported:

Span parentSpan = Span.wrap(SpanContext.createFromRemoteParent(traceId,
                                                               parentSpanId,
                                                               TraceFlags.getSampled(), // NOT getDefault()! 
                                                               TraceState.getDefault()));

Context propagatedContext = Context.current().with(parentSpan);

Span span = tracer.spanBuilder("please-export-me")
                  .setParent(propagatedContext)
                  .startSpan();