public Builder clearExpireTime() {
      bitField0_ = (bitField0_ & ~0x00000002);
      expireTime_ = null;
      if (expireTimeBuilder_ != null) {
        expireTimeBuilder_.dispose();
        expireTimeBuilder_ = null;
      }
      onChanged();
      return this;
    }
<pre>
Time at which the generated token will expire.
</pre>

<code>.google.protobuf.Timestamp expire_time = 2;</code>
java-workstations/proto-google-cloud-workstations-v1beta/src/main/java/com/google/cloud/workstations/v1beta/GenerateAccessTokenResponse.java