@java.lang.Override
      public boolean hasValidAfterDuration() {
        return startTimingConstraintsCase_ == 3;
      }
<pre>
Optional. A relative time after which resources may be created.
</pre>

<code>
.google.protobuf.Duration valid_after_duration = 3 [(.google.api.field_behavior) = OPTIONAL];
</code>

@return Whether the validAfterDuration field is set.
java-tpu/proto-google-cloud-tpu-v2/src/main/java/com/google/cloud/tpu/v2/QueuedResource.java