Method call

[ralf]

I have tryed this one, but it don't work

        if(findProduct(id).getID() != id) or (findProduct(id).getQuantity() == 0)

[Norm]

it don't work

Please explain. There are many ways for code to not work.

[ralf]

I'm trying to return quantity in the item in stock, but when I insert a number which I know not exist then I get a nullpointer

        if(findProduct(id).getID() != id) or (findProduct(id).getQuantity() == 0)

Here I try to see if the id I insert and the product id is different or product id and its quantity is 0
If they are different or 0 return 0, if it is a match between product id and the inserted id then return quantity.
But I have no idea of how to do it correct.
Any suggestion?

[Norm]

I get a nullpointer

You must test for the null return BEFORE you try to use the returned value.
Get a Product reference from findProduct() and test it for null BEFORE you call the getID() method.

[ralf]

Could you please tell me if this look correct
When I use the print out, it print correct number. If write number 2 in the parameter, it print "not a valid number" since there don't exist anything with that number.
If i insert number 37, it print quantity 0.
So it seems to work, but when I try to use the return then I don't know which of the return is returned, since they both return 0

   public int numberInStock(int id)
    {
        if(findProduct(id) == null)
        {
         System.out.println("Not a valid id " + id); 
        }
        else if(findProduct(id).getID() == id)
        {
          // System.out.println("Quantity " + findProduct(id).getQuantity());
           return findProduct(id).getQuantity();
        }else{
             }
      return 0;   
   }

[ralf]

I have tested the code in a debugger an I can see that the correct return is returned. So I think this method work well now.
Thank for your help again Norman!

[Norm]

Does it compile and execute and give you the results that you want?

[ralf]

Yes, it compile and execute and give the result that I want
does it code look correct? It should be correct now

[Norm]

Looks can be deceiving. What matters is: Does it work correctly with all possible test data.

[ralf]

Hello,
Could someone tell me how I can call to a method which is a void method in another class?

[ralf]

I have done it. Its works

[ralf]

I 'm about to write a code to print all details of product below an inserted value
What is most correct, write a new method to do it or write a method which call another print method that allready exist?

I can use this method below to print out product below the inserted value

   public void printProductValue(int value)
   {
       {
        Iterator it = stock.iterator();
        while(it.hasNext())
        {
            Product product = (Product) it.next();
            if(product.getQuantity() < value)
            {
            System.out.println("Product: " + product);
            }
        }
      }
   }