public Builder setDefaultTtl(com.google.protobuf.Duration.Builder builderForValue) {
      if (defaultTtlBuilder_ == null) {
        defaultTtl_ = builderForValue.build();
      } else {
        defaultTtlBuilder_.setMessage(builderForValue.build());
      }
      bitField0_ |= 0x00000008;
      onChanged();
      return this;
    }
<pre>
Optional. The default TTL value for all assets under the corpus without a
asset level user-defined TTL. For STREAM_VIDEO type corpora, this is
required and the maximum allowed
  default_ttl is 10 years.
</pre>

<code>.google.protobuf.Duration default_ttl = 5 [(.google.api.field_behavior) = OPTIONAL];
</code>
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/Corpus.java