Need multiple answers using JOptionPane and if/if else - if-statement

Question

Creating a simple tuition program and I'm getting stuck on (what I think are) the finishing touches.
The issue is I'm not sure how to compute the "hours" variable to remain constant throughout everything once it's been stated.
This is my first year with Java so please excuse my bad style.
import java.util.*;
import javax.swing.JOptionPane;
/**
The application calculates the cost of tuition for one semester at OCC.
*/
public class TuitionOCC
{
public static void main(String[] args)
{
String input;
int residency;
byte credits;
int residentTuition;
int nonTuition;
int internationalTuition;
int hours;
double tuition;
residentTuition = 82;
nonTuition = 154;
internationalTuition = 216;
JOptionPane.showMessageDialog(null, "Calculate your tuition!", "Tuition",JOptionPane.INFORMATION_MESSAGE);
input = JOptionPane.showInputDialog("Are you a:\n" +
"1- College District Resident\n" +
"2- Non-Resident of College District\n" +
"3- Out-of-State or International Student");
residency = Integer.parseInt(input);
if (residency == 1)
{
input = JOptionPane.showInputDialog("How many credit hours are you taking?: ");
hours = Integer.parseInt(input);
if (hours <=0)
JOptionPane.showMessageDialog(null,"You must enter a value of 1 or more.\n" + "Please run the program again", "Error", JOptionPane.ERROR_MESSAGE);
}
else if (residency == 2)
{
residency = nonTuition;
input = JOptionPane.showInputDialog("How many credit hours are you taking?: ");
hours = Integer.parseInt(input);
if (hours <=0)
JOptionPane.showMessageDialog(null,"You must enter a value of 1 or more.\n" + "Please run the program again", "Error", JOptionPane.ERROR_MESSAGE);
}
else if (residency == 3)
{
residency = internationalTuition;
input = JOptionPane.showInputDialog("How many credit hours are you taking?: ");
hours = Integer.parseInt(input);
if (hours <=0)
JOptionPane.showMessageDialog(null,"You must enter a value of 1 or more.\n" + "Please run the program again", "Error", JOptionPane.ERROR_MESSAGE);
}
else
{
JOptionPane.showMessageDialog(null, "You must enter a 1, 2, or 3\n" + "Please run the program again", "Error", JOptionPane.ERROR_MESSAGE);
System.exit(0);
}
tuition = hours * residency;
if
(residency == 1)
{
JOptionPane.showMessageDialog(null, hours + " hours at $ " + residentTuition + "per hour yields a tuition of " + tuition);
}
else if
(residency == 2)
{
JOptionPane.showMessageDialog(null, hours + " hours at $ " + nonTuition + "per hour yields a tuition of " + tuition);
}
else if
(residency == 3)
{
JOptionPane.showMessageDialog(null, hours + " hours at $ " + internationalTuition + "per hour yields a tuition of " + tuition);
}
}
}

Answer 1

If you want to make the hours constant, then you can do something like this:
input = JOptionPane.showInputDialog("How many credit hours are you taking?: ");
final hours = Integer.parseInt(input);
You can also put the JOptionPane on top of if statements so that you will not reassign values on each block of if statements.
Similarly, you can do this to your code to shorten everything.
import java.util.*;
import javax.swing.JOptionPane;
/**
The application calculates the cost of tuition for one semester at OCC.
*/
public class TuitionOCC {
public static void main (String[] args) {
String input;
int residency;
byte credits;
int residentTuition;
int nonTuition;
int internationalTuition;
double tuition;
residentTuition = 82;
nonTuition = 154;
internationalTuition = 216;
JOptionPane.showMessageDialog(null, "Calculate your tuition!", "Tuition",JOptionPane.INFORMATION_MESSAGE);
input = JOptionPane.showInputDialog("Are you a:\n" +
"1- College District Resident\n" +
"2- Non-Resident of College District\n" +
"3- Out-of-State or International Student");
residency = Integer.parseInt(input);
input = JOptionPane.showInputDialog("How many credit hours are you taking?: ");
final int hours = Integer.parseInt(input);
if (hours <= 0) {
JOptionPane.showMessageDialog(null,"You must enter a value of 1 or more.\n" + "Please run the program again", "Error", JOptionPane.ERROR_MESSAGE);
}
else {
tuition = hours * residency;
if (residency == 1) {
JOptionPane.showMessageDialog(null, hours + " hours at $ " + residentTuition + "per hour yields a tuition of " + tuition);
} else if (residency == 2) {
JOptionPane.showMessageDialog(null, hours + " hours at $ " + nonTuition + "per hour yields a tuition of " + tuition);
} else if (residency == 3) {
JOptionPane.showMessageDialog(null, hours + " hours at $ " + internationalTuition + "per hour yields a tuition of " + tuition);
} else {
JOptionPane.showMessageDialog(null, "You must enter a 1, 2, or 3\n" + "Please run the program again", "Error", JOptionPane.ERROR_MESSAGE);
System.exit(0);
}
}
}
}