question: private Buffer checkErrorPacket ( int command ) throws SQLException { Buffer resultPacket = null ; this . serverStatus = 0 ; try { resultPacket = reuseAndReadPacket ( this . reusablePacket ) ; } catch ( SQLException sqlEx ) { throw sqlEx ; } catch ( Exception fallThru ) { throw SQLError . createCommunicationsException ( this . connection , this . lastPacketSentTimeMs , this . lastPacketReceivedTimeMs , fallThru , getExceptionInterceptor ( ) ) ; } checkErrorPacket ( resultPacket ) ; return resultPacket ; }
target:  Checks for errors in the reply packet, and if none, returns the reply packet, ready for reading