private com.google.protobuf.SingleFieldBuilderV3<
              com.google.type.TimeOfDay,
              com.google.type.TimeOfDay.Builder,
              com.google.type.TimeOfDayOrBuilder>
          getStartTimeFieldBuilder() {
        if (startTimeBuilder_ == null) {
          startTimeBuilder_ =
              new com.google.protobuf.SingleFieldBuilderV3<
                  com.google.type.TimeOfDay,
                  com.google.type.TimeOfDay.Builder,
                  com.google.type.TimeOfDayOrBuilder>(
                  getStartTime(), getParentForChildren(), isClean());
          startTime_ = null;
        }
        return startTimeBuilder_;
      }
<pre>
Required. The start time of every automated backup in UTC. It must be set
to the start of an hour. This field is required.
</pre>

<code>.google.type.TimeOfDay start_time = 2 [(.google.api.field_behavior) = REQUIRED];
</code>
java-valkey/proto-google-cloud-valkey-v1/src/main/java/com/google/cloud/memorystore/v1/AutomatedBackupConfig.java