Disappearing Window Content - please help?

Question

Hi,
I'm not very familiar with Java at all, but I have to use it for an assignment, part of which involves randomly generating a maze and displaying it on the screen. I use a JFrame object for displaying.
However, sometimes when I run the program, the maze appears for less than a second, then disappears leaving a blank frame. At other times, the frame is completely empty. And sometimes, the maze is displayed the way it should be (this usually happens after a fresh recompiling). My code runs thus:
public class Test
public static void main(String argv[])
JFrame test = new JFrame("nuts");
test.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
test.setSize(700, 700);
Container content = test.getContentPane();
test.setVisible(true);
// creating maze object called 'maze' here
maze.paint(content.getGraphics());
Here is my paint method:
public void paint (Graphics g) {
int x, y;
for (x = 1; x < 24; ++x)
for (y = 1; y < 39; ++y) {
if ((maze[x][y] & 1) != 0) /* This cell has a top wall */
g.drawLine (x * 10, y * 10, x * 10 + 10, y * 10);
if ((maze[x][y] & 2) != 0) /* This cell has a bottom wall */
g.drawLine (x * 10, y * 10 + 10, x * 10 + 10, y * 10 + 10);
if ((maze[x][y] & 4) != 0) /* This cell has a left wall */
g.drawLine (x * 10, y * 10, x * 10, y * 10 + 10);
if ((maze[x][y] & 8) != 0) /* This cell has a right wall */
g.drawLine (x * 10 + 10, y * 10, x * 10 + 10, y * 10 + 10);
Can anyone please explain to me why my content disappears at times, and is displayed at others? I am in sore need of help, and would be very grateful if someone could give me a hint... If I'm doing something stupid here, my apologies in advance.
Thanks.
MM.

Answer 1

I understand that I didn't set the tags to display my code properly - I'm sorry, I didn't know about it... But I don't quite understand what else I've done wrong. Let me rephrase my question:
I'm trying to print a maze on screen using a JFrame object. Unfortunately, when I run the program (and quit it properly after each time), one of the following happens:
a) The maze is printed correctly.
b) The maze appears for less than a second, then disappears leaving a blank JFrame window.
c) The JFrame window remains blank (which may be the same thing as b, only the maze flashes by too fast for me to notice).
I've gone through a few JFrame tutorials, and I think I've followed the general guidelines. I tried looking for help at other sources - to see if anyone else had trouble with their Jframe content being displayed only sometimes. I even tried setting the Jframe object to always appear on top, but it didn't help. Since I've little experience with coding in Java, I was wondering if someone could please help me by telling me if I'm doing something wrong?
Here's my code:
public class Test extends JFrame
  public static void main(String argv[])
    JFrame test = new JFrame("nuts");
    test.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    test.setSize(700, 700);
    Container content = test.getContentPane();
    test.setVisible(true);
    test.setAlwaysOnTop(true);
    // create object called 'maze' here
    maze.paint(content.getGraphics());
}I don't mean to be rude or anything; nor do I rightly understand what I've done wrong. I'm not trying to leech off anyone; I've honestly tried to figure this out, and I can't. So I'm really hoping someone can please help me. Thank you!