Issues with sorting algorithm

[RAW-BERRY]

I'm trying to implement a sorting algorithm for my HairSalon class that sorts a HairSalon array in ascending order by price. The getPrice() method returns the price of the service for that element. During runtime immediately after inputting the data, I keep getting the error "java.lang.NullPointerException: Null", and I'm unsure as to why.


Here is the sorting part.

    public static void priceAscend(HairSalon[] item, int size)
    {
        for (int k = 0; k < size - 1; k++)
            swapMinToFront (item, k, size - 1);
    }
    
    private static void swapMinToFront (HairSalon[] item, int start, int end)
    { 
        int indexSmallest = start;
        for (int k = start + 1; k <= end; k++)
        { 
            if (item[k].getPrice() < item[indexSmallest].getPrice())
            indexSmallest = k;
        }
        HairSalon saved = item[start];
        item[start] = item[indexSmallest];
        item[indexSmallest] = saved;
    } //=======================
}

or alternatively

    public static void priceAscend(HairSalon[] par)
    {
        for(int x = 0; x < 6 - 1; x++) {
            int smallest = x;
            for(int y = 1; y < par.length - 1; y++) {
                if(par[y].getPrice() < par[y-1].getPrice()) {
                    smallest = y;
                }
            }
            HairSalon saved = par[x];
            par[x] = par[smallest];
            par[smallest] = saved;
        }
    }

You fill each array manually, and then it sorts the array.

    public static void main (String[] args)
    {
        HairSalon[] salonList = new HairSalon[6];
        for(int x = 0; x < 6; x++) {
            salonList[x].service = JOptionPane.showInputDialog("Hair Salon "+(x+1)+" service:");
            salonList[x].price = Double.parseDouble(JOptionPane.showInputDialog("Hair Salon "+(x+1)+" price:"));
            salonList[x].minutes = Integer.parseInt(JOptionPane.showInputDialog("Hair Salon "+(x+1)+" minutes:"));
        }
        priceAscend(salonList, 6);
        String s = "";
        for(int x = 0; x < 6; x++) {
            s += salonList[x].getPrice() + " ";
        }
        JOptionPane.showMessageDialog(null, s);
    }

In case you need to look at the actual class, here it is.

public class HairSalon
{
    public static String service;
    public static double price;
    public static int minutes;

    public void HairSalon(String serv, double cost, int mins)
    {
        service = serv;
        price = cost;
        minutes = mins;
    }
    
    public double getPrice()
    {
        return price;
    }
    
    public String getService()
    {
        return service;
    }
    
    public int getTime()
    {
        return minutes;
    }
}

Thanks in advance for any help with this issue!

[KevinWorkman]

Are you sure you're getting that error at compile-time? NullPointerExceptions are a runtime Exception, not a compile-time error. Also, what is the full stack trace for the Exception? What line is it occurring on?

[RAW-BERRY]

Yes, sorry. It is a runtime error which occurs immediately after inputing all appropriate data.