public Builder mergeTtl(com.google.protobuf.Duration value) {
      if (ttlBuilder_ == null) {
        if (((bitField0_ & 0x00000004) != 0)
            && ttl_ != null
            && ttl_ != com.google.protobuf.Duration.getDefaultInstance()) {
          getTtlBuilder().mergeFrom(value);
        } else {
          ttl_ = value;
        }
      } else {
        ttlBuilder_.mergeFrom(value);
      }
      if (ttl_ != null) {
        bitField0_ |= 0x00000004;
        onChanged();
      }
      return this;
    }
<pre>
The duration for which all media assets, associated metadata, and search
documents can exist.
</pre>

<code>.google.protobuf.Duration ttl = 3;</code>
java-visionai/proto-google-cloud-visionai-v1/src/main/java/com/google/cloud/visionai/v1/MediaWarehouseConfig.java