private com.google.protobuf.SingleFieldBuilderV3<
              com.google.protobuf.Duration,
              com.google.protobuf.Duration.Builder,
              com.google.protobuf.DurationOrBuilder>
          getStartOffsetFieldBuilder() {
        if (startOffsetBuilder_ == null) {
          startOffsetBuilder_ =
              new com.google.protobuf.SingleFieldBuilderV3<
                  com.google.protobuf.Duration,
                  com.google.protobuf.Duration.Builder,
                  com.google.protobuf.DurationOrBuilder>(
                  getStartOffset(), getParentForChildren(), isClean());
          startOffset_ = null;
        }
        return startOffsetBuilder_;
      }
<pre>
Start time offset of the partition.
</pre>

<code>.google.protobuf.Duration start_offset = 1;</code>
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/Partition.java