Dúvida com o printf

package cap4.exe17;

import java.util.Scanner;

public class ConsumoTanque {
	
	public void calculoConsumo(){
	
	int km;
	int litrosComb;
	float totalConsumo = 0;
	float totalLitros = 0;
	
	Scanner input = new Scanner (System.in);
	
	
		System.out.print ( "Entre com o km do veículo: " );
		km = input.nextInt();
	
		System.out.print ( "Entre com o consumo de gasolina: ");
		litrosComb = input.nextInt();
	
	while (km != -1 || litrosComb != -1){
		totalConsumo = (float)km / litrosComb; 
		totalLitros += litrosComb;
	}
	
		System.out.printf( "\nTotal Consumo: %.3f",totalConsumo );
		System.out.printf( "\nTotal Litros: %.3f",totalLitros );

	}
}

package cap4.exe17;

public class ConsumoTanqueTest {
	
	public static void main (String [] args){
		
		ConsumoTanque consumoTanque = new ConsumoTanque ();
		
		consumoTanque.calculoConsumo();
		
		System.exit (0);
	}

}