import io.opentracing.Tracer;
import static io.opentracing.References.CHILD_OF;
import static io.opentracing.References.FOLLOWS_FROM;
public class SpanBuilder implements Tracer.SpanBuilder {
static final String PARENT_SPAN_GUID_KEY = "parent_span_guid";
<BUG>private final String operationName;
private Long spanId = null;</BUG>
private final Map<String, String> tags;
private final AbstractTracer tracer;
private SpanContext parent;

import io.opentracing.Tracer;
import static io.opentracing.References.CHILD_OF;
import static io.opentracing.References.FOLLOWS_FROM;
public class SpanBuilder implements Tracer.SpanBuilder {
static final String PARENT_SPAN_GUID_KEY = "parent_span_guid";
private final String operationName;
private Long traceId = null;
private Long spanId = null;
private final Map<String, String> tags;
private final AbstractTracer tracer;
private SpanContext parent;
