How to replace an existing data in an array

[Xdawn90]

Right now i have an array of objects. Each object contain code, name, price and amount.

1. How am I going to add an object containing all those properties into the array ?

2. How am I going to edit(replace with new properties) the properties of the object inside the array ?

Please help.

Thanks very much.

[WingedPanther]

Arrays

[Sinipull]

also, i would recommend you learn about ArrayList and LinkedList, which are much easier to use than regular arrays.

[Xdawn90]

I have a question here:

why am I getting a nullpointerexception in this code ?

public class Showroom{

   private Vehicle stocks[];   
   private double width;
   private double height;
   private double length;

//--------------------------------
   
   public Showroom(){
	  stocks[0]=new Vehicle();
	  stocks[1]=new Vehicle();
	  stocks[2]=new Vehicle();
	  stocks[3]=new Vehicle();
	  stocks[4]=new Vehicle();
      width=0.0;
      height=0.0;
      length=0.0;
   }
   public void setStocks(Vehicle v, int x){
      stocks[x]=v;
   }
   public Vehicle getStocks(int x){
      return stocks[x];
   }
   public double calculateArea(){
      return width*height*length;
   }
   public void setWidth(double a){
      width=a;
   }
   public double getWidth(){
      return width;
   }
   public void setHeight(double b){
      height=b;
   }
   public double getHeight(){
      return height;
   }
   public void setLength(double c){
      length=c;
   }
   public double getLength(){
      return length;
   }
   public static void main(String args[]){
      Showroom s = new Showroom();
	  Vehicle myVehicle;
	  myVehicle = new Vehicle("abc", "green", 3, 3, 3);
	  s.setStocks(myVehicle, 0);
      System.out.println(s.getStocks(0));
   }
}

The one in red is the one that the compiler complaining about. Can you tell me what is wrong with that ? I really cant figure out what is wrong.

Thanks.

[Sinipull]

instead of

private Vehicle stocks[];

try that...

private Vehicle stocks[] = new Vehicle[sizeOfArray];

[Turk4n]

Your stocks and vehicle, are they separate classes or what?

[Sinipull]

i think "stocks" is just the name of array..

[Turk4n]

i think "stocks" is just the name of array..

If thats so, then where is the vehicle class?

[Sinipull]

Guess he didn't show us that, it doesn't matter anyway...
i already posted the solution and i'm quite sure, it will fix it.

[Turk4n]

Guess he didn't show us that, it doesn't matter anyway...
i already posted the solution and i'm quite sure, it will fix it.

Good