public Builder mergeFrom(com.google.devtools.cloudtrace.v2.Span other) {
      if (other == com.google.devtools.cloudtrace.v2.Span.getDefaultInstance()) return this;
      if (!other.getName().isEmpty()) {
        name_ = other.name_;
        bitField0_ |= 0x00000001;
        onChanged();
      }
      if (!other.getSpanId().isEmpty()) {
        spanId_ = other.spanId_;
        bitField0_ |= 0x00000002;
        onChanged();
      }
      if (!other.getParentSpanId().isEmpty()) {
        parentSpanId_ = other.parentSpanId_;
        bitField0_ |= 0x00000004;
        onChanged();
      }
      if (other.hasDisplayName()) {
        mergeDisplayName(other.getDisplayName());
      }
      if (other.hasStartTime()) {
        mergeStartTime(other.getStartTime());
      }
      if (other.hasEndTime()) {
        mergeEndTime(other.getEndTime());
      }
      if (other.hasAttributes()) {
        mergeAttributes(other.getAttributes());
      }
      if (other.hasStackTrace()) {
        mergeStackTrace(other.getStackTrace());
      }
      if (other.hasTimeEvents()) {
        mergeTimeEvents(other.getTimeEvents());
      }
      if (other.hasLinks()) {
        mergeLinks(other.getLinks());
      }
      if (other.hasStatus()) {
        mergeStatus(other.getStatus());
      }
      if (other.hasSameProcessAsParentSpan()) {
        mergeSameProcessAsParentSpan(other.getSameProcessAsParentSpan());
      }
      if (other.hasChildSpanCount()) {
        mergeChildSpanCount(other.getChildSpanCount());
      }
      if (other.spanKind_ != 0) {
        setSpanKindValue(other.getSpanKindValue());
      }
      this.mergeUnknownFields(other.getUnknownFields());
      onChanged();
      return this;
    }
<pre>
A span represents a single operation within a trace. Spans can be
nested to form a trace tree. Often, a trace contains a root span
that describes the end-to-end latency, and one or more subspans for
its sub-operations.

A trace can also contain multiple root spans, or none at all.
Spans do not need to be contiguous. There might be
gaps or overlaps between spans in a trace.
</pre>

Protobuf type {@code google.devtools.cloudtrace.v2.Span}
java-trace/proto-google-cloud-trace-v2/src/main/java/com/google/devtools/cloudtrace/v2/Span.java