public Builder mergeStackFrames(
        com.google.devtools.cloudtrace.v2.StackTrace.StackFrames value) {
      if (stackFramesBuilder_ == null) {
        if (((bitField0_ & 0x00000001) != 0)
            && stackFrames_ != null
            && stackFrames_
                != com.google.devtools.cloudtrace.v2.StackTrace.StackFrames.getDefaultInstance()) {
          getStackFramesBuilder().mergeFrom(value);
        } else {
          stackFrames_ = value;
        }
      } else {
        stackFramesBuilder_.mergeFrom(value);
      }
      if (stackFrames_ != null) {
        bitField0_ |= 0x00000001;
        onChanged();
      }
      return this;
    }
<pre>
Stack frames in this stack trace. A maximum of 128 frames are allowed.
</pre>

<code>.google.devtools.cloudtrace.v2.StackTrace.StackFrames stack_frames = 1;</code>
java-trace/proto-google-cloud-trace-v2/src/main/java/com/google/devtools/cloudtrace/v2/StackTrace.java