@java.lang.Override
    public boolean hasTtl() {
      return expirationCase_ == 14;
    }
<pre>
Input only. The time-to-live (TTL) or duration for the subscription. If
unspecified or set to `0`, uses the maximum possible duration.
</pre>

<code>.google.protobuf.Duration ttl = 14 [(.google.api.field_behavior) = INPUT_ONLY];</code>

@return Whether the ttl field is set.
java-workspaceevents/proto-google-cloud-workspaceevents-v1/src/main/java/com/google/apps/events/subscriptions/v1/Subscription.java