title: Java - How to initialize parameters for an object?
body: <p>I have been struggling with this issue for weeks and still cannot get what I need. My CalculatingRocketFlightProfile class holds the <strong>constructor with the parameters</strong> (totalImpulse, averageImpulse etc...) and the methods which calculates the outputs. My MAIN class has an object which inherits my keyboard entry class. This allows users to <strong>input a number</strong>. Now, all I need is to use these inputs and <strong>calculate a result (using the methods in the CalculatingRocketFlightProfile class)  to be displayed</strong>. However my object of CalculatingRocketFlightProfile class <strong>wont acceppt any parameters</strong> or I simply doing something wronng. Please help me out I'm really frustrated. </p>
  
  <pre><code>//CalculatingRocketFlightProfile class
  
  public class CalculatingRocketFlightProfile { //Calculation class
  
  //Declaring fields
  public double totalImpulse ;
  public double averageImpulse;
  public double timeEjectionChargeFires;
  public double massEmptyVehicle;
  public double engineMass;
  public double fuelMass; 
  //Declaring variables for outputs
  public double theAverageMassOfTheVehicle; //declare variables to store  results of calculations
  public double theVehiclesMaximumVelocity;
  
  
  public CalculatingRocketFlightProfile(double totalImpulse, double averageImpulse, double timeEjectionChargeFires, double massEmptyVehicle,
                                    double engineMass, double fuelMass) { //Setting the parameters
  
  this.totalImpulse  = totalImpulse;
  this.averageImpulse = averageImpulse;
  this.timeEjectionChargeFires = timeEjectionChargeFires;
  this.massEmptyVehicle = massEmptyVehicle;
  this.engineMass = engineMass;
  this.fuelMass = fuelMass;
  }
  
  //Mutators and Accessors
  
  //Accessors
  //Methods for calculations - Calculating outputs, using inputs. 
  
  public double theAverageMassOfTheVehicle() {
      return massEmptyVehicle + ((engineMass + (engineMass - fuelMass) )/ 2); //Formula to calculate Average mass 
  }//method
  
  public double theVehiclesMaximumVelocity() { //Formula to calculate Maximum velocity
      return totalImpulse / getTheAverageMassOfTheVehicle();
  }//method
  
  
  //Mutators - SET
  public void setTheAverageMassOfTheVehicle(double theAverageMassOfTheVehicle)       {
      this.theAverageMassOfTheVehicle = theAverageMassOfTheVehicle;
  }//method
  
  public void setTheVehiclesMaximumVelocity(double theVehiclesMaximumVelocity) {
      this.theVehiclesMaximumVelocity = theVehiclesMaximumVelocity;
  }//method
  
  //Getters
  
  public double getTheAverageMassOfTheVehicle() {
      return theAverageMassOfTheVehicle;
  }//method
  
  public double getTheVehiclesMaximumVelocity() {
      return theVehiclesMaximumVelocity;
  }//method
  
  }//class
  
  
  public class Main { //Master class
      public static void main( String args[] ) //Standard header for main  method
      {
      kbentry input = new kbentry();
  
      System.out.print("\nPlease enter a number for Total Impulse: " );
      System.out.println("You have entered : " +input.totalImpulse1());
  
  
      System.out.print("\nPlease enter a number for Average Impulse: " );
      System.out.println("You have entered : " +input.averageImpulse2());
  
      System.out.print("\nPlease enter a number for Time ejection charge fires: " );
      System.out.println("You have entered : " +input.timeEjectionChargeFires3());
  
      System.out.print("\nPlease enter a number for the Mass of the vehicle: " );
      System.out.println("You have entered : " +input.massEmptyVehicle4());
  
      System.out.print("\nPlease enter a number for the Mass of the engine: " );
      System.out.println("You have entered : " +input.engineMass5());
  
      System.out.print("\nPlease enter a number for the Mass of the fuel: " );
      System.out.println("You have entered : " +input.fuelMass6());
  
      //Output
  
  
      CalculatingRocketFlightProfile calculations = new CalculatingRocketFlightProfile(totalImpulse,averageImpulse,timeEjectionChargeFires,massEmptyVehicle,engineMass,fuelMass );    //This will give me an error "cant find variables"
  
      System.out.println("\nThe average mass of the vehicle: " +calculations.theAverageMassOfTheVehicle() +
                         "\nThe vehicles maximum velocity: " + calculations.theVehiclesMaximumVelocity());
      }
  }
  
  
  //kbentry class  (Same for all methods e.g. averageImpulse2, timeEjectionChargeFires3 etc...)
  
  public class kbentry{
  
  double totalImpulse1(){
  
  BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
  
  //Total Impulse entry
  String strTotalImpulse = null;  // These must be initialised
  int    intTotalImpulse = 0;
  
  //System.out.print("Please enter a number for Total Impulse: ");
  //System.out.flush();
  
  // read string value from keyboard
  try {
    strTotalImpulse = in.readLine();
  } 
  catch (IOException ioe) { 
    // ignore exception
  }
  </code></pre>