TagMetadataKey Node1 TagMetadataKey - m_verstat - m_encoded + TagMetadataKey() + TagMetadataKey() + setEncoded() + setKey() + setQual() + setIOV() + setVersion() + isVersioned() + encoded() + key() + qual() + iov() + ver() + fromString() + toString() + sep() + keymark() + qualmark() + iovmark() + vermark() - getpayload() Node2 std::string Node2->Node1 -m_qual -m_key -m_iov -m_ver Node3 std::basic_string< char > Node3->Node2