private com.google.protobuf.RepeatedFieldBuilderV3<
            com.google.devtools.cloudtrace.v1.TraceSpan,
            com.google.devtools.cloudtrace.v1.TraceSpan.Builder,
            com.google.devtools.cloudtrace.v1.TraceSpanOrBuilder>
        getSpansFieldBuilder() {
      if (spansBuilder_ == null) {
        spansBuilder_ =
            new com.google.protobuf.RepeatedFieldBuilderV3<
                com.google.devtools.cloudtrace.v1.TraceSpan,
                com.google.devtools.cloudtrace.v1.TraceSpan.Builder,
                com.google.devtools.cloudtrace.v1.TraceSpanOrBuilder>(
                spans_, ((bitField0_ & 0x00000004) != 0), getParentForChildren(), isClean());
        spans_ = null;
      }
      return spansBuilder_;
    }
<pre>
Collection of spans in the trace.
</pre>

<code>repeated .google.devtools.cloudtrace.v1.TraceSpan spans = 3;</code>
java-trace/proto-google-cloud-trace-v1/src/main/java/com/google/devtools/cloudtrace/v1/Trace.java