public com.google.protobuf.DurationOrBuilder getTtlOrBuilder() {
      if (ttlBuilder_ != null) {
        return ttlBuilder_.getMessageOrBuilder();
      } else {
        return ttl_ == null ? com.google.protobuf.Duration.getDefaultInstance() : ttl_;
      }
    }
<pre>
Optional. TTL for the backup to expire. Value range is 1 day to 100 years.
If not specified, the default value is 100 years.
</pre>

<code>.google.protobuf.Duration ttl = 2 [(.google.api.field_behavior) = OPTIONAL];</code>
java-valkey/proto-google-cloud-valkey-v1/src/main/java/com/google/cloud/memorystore/v1/BackupInstanceRequest.java