public Builder mergeStartTime(com.google.protobuf.Timestamp value) {
        if (startTimeBuilder_ == null) {
          if (((bitField0_ & 0x00000001) != 0)
              && startTime_ != null
              && startTime_ != com.google.protobuf.Timestamp.getDefaultInstance()) {
            getStartTimeBuilder().mergeFrom(value);
          } else {
            startTime_ = value;
          }
        } else {
          startTimeBuilder_.mergeFrom(value);
        }
        if (startTime_ != null) {
          bitField0_ |= 0x00000001;
          onChanged();
        }
        return this;
      }
<pre>
Start time of the partition.
</pre>

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