public com.google.protobuf.Timestamp getDwellStartTime() {
        if (dwellStartTimeBuilder_ == null) {
          return dwellStartTime_ == null
              ? com.google.protobuf.Timestamp.getDefaultInstance()
              : dwellStartTime_;
        } else {
          return dwellStartTimeBuilder_.getMessage();
        }
      }
<pre>
The beginning time when a dwelling object has been identified in a zone.
</pre>

<code>.google.protobuf.Timestamp dwell_start_time = 3;</code>

@return The dwellStartTime.
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/OccupancyCountingPredictionResult.java