MuonVal::MetaDataAlg::RunMetaData Node1 MuonVal::MetaDataAlg ::RunMetaData + run_number + tot_events + proc_events + has_book_keeper + ~RunMetaData() + RunMetaData() + operator<() Node2 std::string     Node2->Node1 +trigger_stream Node3 std::basic_string< Char >     Node3->Node2 Node4 std::set< unsigned int > + keys   Node4->Node1 +processed_blocks +total_lumi_blocks