question: @ Override public boolean input ( Instance instance ) { if ( getInputFormat ( ) == null ) { throw new IllegalStateException ( "No input instance format defined" ) ; } if ( m_NewBatch ) { resetQueue ( ) ; m_NewBatch = false ; } if ( isFirstBatchDone ( ) && m_dontFilterAfterFirstBatch ) { push ( ( Instance ) instance . copy ( ) ) ; return true ; } if ( instance . isMissing ( m_AttIndex . getIndex ( ) ) ) { if ( ! getMatchMissingValues ( ) ) { push ( ( Instance ) instance . copy ( ) ) ; return true ; } else { return false ; } } if ( isNumeric ( ) ) { if ( ! m_Values . getInvert ( ) ) { if ( instance . value ( m_AttIndex . getIndex ( ) ) < m_Value ) { push ( ( Instance ) instance . copy ( ) ) ; return true ; } } else { if ( instance . value ( m_AttIndex . getIndex ( ) ) >= m_Value ) { push ( ( Instance ) instance . copy ( ) ) ; return true ; } } } if ( isNominal ( ) ) { if ( m_Values . isInRange ( ( int ) instance . value ( m_AttIndex . getIndex ( ) ) ) ) { Instance temp = ( Instance ) instance . copy ( ) ; if ( getModifyHeader ( ) ) { temp . setValue ( m_AttIndex . getIndex ( ) , m_NominalMapping [ ( int ) instance . value ( m_AttIndex . getIndex ( ) ) ] ) ; } push ( temp ) ; return true ; } } return false ; }
target:  Input an instance for filtering. Ordinarily the instance is processed and made available for output immediately. Some filters require all instances be read before producing output.