Help with code please

Question

Hi, I am new to Java and am trying to write a program for a class, but I can't seem to get it to work correctly.
The program is supposed to ask you to enter "A,B,C, or Q" and be case sensitive. If you enter A,B,C you get a message, if you enter Q it quits the program and if you enter anything else you are supposed to get an error message. It is supposed to keep looping the program until the user enters Q. We are supposed to use Do--While and If-Else loops.
Thanks in advance
Code Below that I am using (it at least compiles :) )
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class abcprogram
public static void main(String[] args)
String grade;
grade = JOptionPane.showInputDialog("Please enter A, B, C, or Q. Program is case sensitive");
do
if (grade.equals("A"))
JOptionPane.showInputDialog("Good Work");
else if (grade.equals("B"))
JOptionPane.showInputDialog("Try Harder");
else if (grade.equals("C"))
JOptionPane.showInputDialog("Did you study?");
else if (grade.equals("Q"))
System.exit(0);
else
JOptionPane.showInputDialog("You entered a wrong letter!");
}while (grade != "Q");
}

Answer 1

One other thing: the while condidtion should read
while (!grade.equals("Q"))
Try it like this;-import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class abc {
public static void main(String[] args){
String grade, enter;
grade = JOptionPane.showInputDialog
("Please enter A, B, C, or Q. The program
he program is case sensitive");
do {     
if (grade.equals("A")) grade =
)) grade = JOptionPane.showInputDialog
("Good Work.
("Good Work. (Enter Q to
("Good Work. (Enter Q to quit)");
else if (grade.equals("B")) grade =
)) grade = JOptionPane.showInputDialog
("Try
("Try Harder.
("Try Harder. (enter Q to
("Try Harder. (enter Q to quit)");
else if (grade.equals("C")) grade =
)) grade = JOptionPane.showInputDialog
("Did
("Did you
("Did you study? (Enter
("Did you study? (Enter Q to quit)");
else if (grade.equals("Q"))
uals("Q")) System.exit(0);
else JOptionPane.showInputDialog("You
ialog("You entered a wrong letter!");
while (grade != "Q");}