question: public static void appendInstruction ( OFFlowMod . Builder fmb , OFInstruction inst ) { List < OFInstruction > newIl = new ArrayList < OFInstruction > ( ) ; List < OFInstruction > oldIl = fmb . getInstructions ( ) ; if ( oldIl != null ) { newIl . addAll ( fmb . getInstructions ( ) ) ; } for ( OFInstruction i : newIl ) { if ( i . getType ( ) == inst . getType ( ) ) { newIl . remove ( i ) ; } } newIl . add ( inst ) ; fmb . setInstructions ( newIl ) ; }
target:  Adds the instructions to the list of OFInstructions in the OFFlowMod. Any pre-existing instruction of the same type is replaced with OFInstruction inst.