private void ensureWeeklyMaintenanceWindowIsMutable() {
      if (!((bitField0_ & 0x00000004) != 0)) {
        weeklyMaintenanceWindow_ =
            new java.util.ArrayList<com.google.cloud.memorystore.v1.WeeklyMaintenanceWindow>(
                weeklyMaintenanceWindow_);
        bitField0_ |= 0x00000004;
      }
    }
<pre>
Output only. The time when the policy was updated.
</pre>

<code>
.google.protobuf.Timestamp update_time = 2 [(.google.api.field_behavior) = OUTPUT_ONLY];
</code>
java-valkey/proto-google-cloud-valkey-v1/src/main/java/com/google/cloud/memorystore/v1/MaintenancePolicy.java