@java.lang.Override
    public int getSerializedSize() {
      int size = memoizedSize;
      if (size != -1) return size;

      size = 0;
      if (authMethod_
          != com.google.storagetransfer.v1.proto.TransferTypes.S3CompatibleMetadata.AuthMethod
              .AUTH_METHOD_UNSPECIFIED
              .getNumber()) {
        size += com.google.protobuf.CodedOutputStream.computeEnumSize(1, authMethod_);
      }
      if (requestModel_
          != com.google.storagetransfer.v1.proto.TransferTypes.S3CompatibleMetadata.RequestModel
              .REQUEST_MODEL_UNSPECIFIED
              .getNumber()) {
        size += com.google.protobuf.CodedOutputStream.computeEnumSize(2, requestModel_);
      }
      if (protocol_
          != com.google.storagetransfer.v1.proto.TransferTypes.S3CompatibleMetadata.NetworkProtocol
              .NETWORK_PROTOCOL_UNSPECIFIED
              .getNumber()) {
        size += com.google.protobuf.CodedOutputStream.computeEnumSize(3, protocol_);
      }
      if (listApi_
          != com.google.storagetransfer.v1.proto.TransferTypes.S3CompatibleMetadata.ListApi
              .LIST_API_UNSPECIFIED
              .getNumber()) {
        size += com.google.protobuf.CodedOutputStream.computeEnumSize(4, listApi_);
      }
      size += getUnknownFields().getSerializedSize();
      memoizedSize = size;
      return size;
    }
<pre>
The Listing API to use for discovering objects. When not specified,
Transfer Service will attempt to determine the right API to use.
</pre>

<code>.google.storagetransfer.v1.S3CompatibleMetadata.ListApi list_api = 4;</code>

@return The listApi.
java-storage-transfer/proto-google-cloud-storage-transfer-v1/src/main/java/com/google/storagetransfer/v1/proto/TransferTypes.java