@java.lang.Override
    public final Builder setUnknownFields(final com.google.protobuf.UnknownFieldSet unknownFields) {
      return super.setUnknownFields(unknownFields);
    }
<pre>
Optional. If set to `true`, validates and previews the request, but doesn't
update the subscription.
</pre>

<code>bool validate_only = 3 [(.google.api.field_behavior) = OPTIONAL];</code>

@return This builder for chaining.
java-workspaceevents/proto-google-cloud-workspaceevents-v1/src/main/java/com/google/apps/events/subscriptions/v1/UpdateSubscriptionRequest.java