question: public static double discharge ( ItemStack itemStack , double amount ) { if ( itemStack != null ) { if ( itemStack . getItem ( ) instanceof IEnergizedItem ) { IEnergizedItem energizedItem = ( IEnergizedItem ) itemStack . getItem ( ) ; if ( energizedItem . canSend ( itemStack ) ) { double energyToUse = Math . min ( energizedItem . getMaxTransfer ( itemStack ) , Math . min ( energizedItem . getEnergy ( itemStack ) , amount ) ) ; energizedItem . setEnergy ( itemStack , energizedItem . getEnergy ( itemStack ) - energyToUse ) ; return energyToUse ; } } } return 0 ; }
target:  Discharges an IEnergizedItem with the defined amount of energy.