@java.lang.Override
  public boolean hasTtl() {
    return ((bitField0_ & 0x00000001) != 0);
  }
<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>

@return Whether the ttl field is set.
java-valkey/proto-google-cloud-valkey-v1/src/main/java/com/google/cloud/memorystore/v1/BackupInstanceRequest.java