I have a home work assignment that I am having trouble
with, if anyone could help me in any way that would be
cool. I am not asking you to code it for me. just asking
for tips. because here is what I have so far. And its all screwed
up. I just need some help.

import javax.swing.JOptionPane;


public class salary {
public static void main ( String args [] ){




int item1,
item2,
item3,
item4,
itemCounter = 0,
total = 0;

string itemNumber;


double sum;

itemNumber = Integer.ParseInt(JOptionPane.showInputDialog("Please
enter the Item number (-1 when done):"));


while ( itemNumber != -1 ) {
total = total + itemNumber;
itemCounter = itemCounter + 1;

itemNumber = Integer.ParseInt(JOptionPane.showInputDialog("Please
enter the Item number (-1 when done):"));


switch ( itemNumber ) {
case item1:






}
}


System.exit (0);
}
}


The problem is this: Develop a Java Application that inputs
one salesperson's items sold for the last week and calculates
and displays that salesperson's earnings. There is no limit
to a the number of items sold by a salesperson.
The items are 1 at $239.99, 2 at $129.75, 3 at 99.95, and 4 at 350.89.


The salesperson gets $200.00 plus 9% of the total earnings.