public Builder clearTravelDuration() {
      bitField0_ = (bitField0_ & ~0x00000004);
      travelDuration_ = null;
      if (travelDurationBuilder_ != null) {
        travelDurationBuilder_.dispose();
        travelDurationBuilder_ = null;
      }
      onChanged();
      return this;
    }
<pre>
Required. The maximum travel time in seconds. The maximum allowed value is
`3600s` (one hour). Format is `123s`.
</pre>

<code>
.google.protobuf.Duration travel_duration = 3 [(.google.api.field_behavior) = REQUIRED];
</code>
java-talent/proto-google-cloud-talent-v4beta1/src/main/java/com/google/cloud/talent/v4beta1/CommuteFilter.java