I think this is weird because when I ran it before on Eclipse, this program worked. However, when I try to run it using 'java PacMan', then nothing shows up. I think it is because I am missing a main method, but I'm not sure how to integrate that into my program without screwing everything up.
/*
PacMan.java
This is a lame replica of the game PacMan. The PacMan
starts out on a random location on the board with
6 ghosts & cheese. It must try to eat the cheese without
getting eaten by the ghosts. The ghosts only move around
when PacMan does. All characters on the board can only move
around when PacMan does and can only move up, down, left,
and right; diagonal movement isn't allowed. When PacMan eats
all the cheese, the words 'YOU WIN! :)' will be displayed across
the board; if you lose, 'YOU LOST! :(' will be shown.
*/
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class PacMan extends JApplet implements KeyListener
{
private int chez, ghosts;
private int currentx, currenty, direction, a;
private int [][] grid;
private int [] alienx, alieny;
private DrawingArea canvas;
private boolean lost;
public void init()
{
setSize(500, 560);
generateBoard();
canvas = new DrawingArea(); // drawing area
getContentPane().add(canvas, BorderLayout.CENTER);
JPanel buttonPanel = new ButtonPanel();
getContentPane().add(buttonPanel, BorderLayout.SOUTH);
canvas.setBackground(Color.black);
canvas.addKeyListener(this);
canvas.requestFocus();
}
public void generateBoard()
{
lost = false;
chez = ghosts = currentx = currenty = 0;
grid = new int[10][10]; // sets 2D array size
alienx = new int[6];
alieny = new int[6];
do
{
currentx = (int)(Math.random() * 10);
currenty = (int)(Math.random() * 10);
if(grid[currentx][currenty] == 0 && chez < 6)
{
grid[currentx][currenty] = 1; // placement holder because 0 won't be read in
chez++; // '1' is the cheese
}
if(grid[currentx][currenty] == 0 && ghosts < 6)
{
grid[currentx][currenty] = 2; // placement holder because 0 won't be read in
alienx[ghosts] = currentx;
alieny[ghosts] = currenty;
ghosts++; // '2' is the ghosts
}
}
while(chez < 6 || ghosts < 6);
do // this makes sure PacMan never respawns on a ghost or cheese
{
currentx = (int)(Math.random() * 10);
currenty = (int)(Math.random() * 10);
}
while(grid[currentx][currenty] != 0);
grid[currentx][currenty] = 3; // this is PacMan
direction = 0;
}
public void moveGhosts(int a)
{
int oldx = alienx[a], oldy = alieny[a]; // coordinates of the aliens
grid[oldx][oldy] = 0; // erases original spacing for monster/alien
int stuff; // used for random statement
boolean done = true;
stuff = (int)(Math.random() * 8 + 1); // amount of random moves XD
do
{
switch(stuff)
{
case 1: alienx[a]++; break; // down
case 2: alienx[a]--; break; // up
case 3: alieny[a]++; break; // right
case 4: alieny[a]--; break; // left
case 5: alienx[a]++; alieny[a]--; break; // down, left
case 6: alienx[a]++; alieny[a]++; break; // down, right
case 7: alienx[a]--; alieny[a]--; break; // up, left
case 8: alienx[a]--; alieny[a]++; break; // up, right
}
if(alieny[a] == 10)
alieny[a] = 0;
if(alieny[a] == -1)
alieny[a] = 9;
if(alienx[a] == 10)
alienx[a] = 0;
if(alienx[a] == -1)
alienx[a] = 9;
if(grid[alienx[a]][alieny[a]] == 0 || grid[currentx][currenty] == 3)
done = true; // only runs when ghost is on empty space or eats PacMan
else
done = false; // makes sure ghost never eats cheese
for(int b = 0; b < 6; b++)
if(alienx[b] == alienx[a] && alieny[b] == alieny[a] && b != a)
done = false; // prevents ghosts from overlaping each other
if (!done)
{
oldx = alienx[a];
oldy = alieny[a];
}
} while (!done);
grid[alienx[a]][alieny[a]] = 2;
}
class DrawingArea extends JPanel
{
public void paintComponent(Graphics g)
{
super.paintComponent(g);
displayBoard(g);
this.requestFocus();
}
public void displayBoard(Graphics g)
{
g.setColor(Color.gray);
g.fillRect(116, 464, 270, 50); // gray background for board
g.fillRect(30, 10, 445, 445); // gray background for 'cheese remaining'
g.setColor(Color.yellow);
g.drawRect(116, 464, 270, 50); // outlines 'cheese remaining' box
if(grid[currentx][currenty] == 1) // makes cheese disappear when PacMan eats it
{
grid[currentx][currenty] = 0;
chez--;
}
if(grid[currentx][currenty] == 2) // makes PacMan disappear when he hits a ghost
lost = true;
Font progress = new Font("Sans Serif", Font.PLAIN, 25);
g.setFont(progress);
if(!lost && chez > 0)
g.drawString("Cheese Remaining:"+ chez, 130, 500); // shows # of cheese left
else if(lost == true)
g.drawString("YOU LOST! :(", 175, 500);
else if(chez == 0)
g.drawString("YOU WON! :)", 175, 500);
g.setColor(Color.white);
for(int row = 0; row < grid.length; row++)
for(int col = 0; col < grid[row].length; col++)
{
g.setColor(Color.white);
g.fillRect(30 + col * 45, 10 + row * 45, 40, 40); // prints grid
g.setColor(Color.blue); // primitive PacMan
if(!lost)
g.fillArc(30 + currentx * 45, 10 + currenty * 45, 40, 40, direction + 30, 300);
if(grid[col][row] == 1) // prints out cheese randomly if array encounters invisible '1'
{
// while scanning
g.setColor(Color.yellow);
g.fillRect(33 + col * 45, 13 + row * 45, 33, 33); // blocks of cheese
}
if(grid[col][row] == 2) // prints out ghosts randomly if array encounters invisible '2'
{
// while scanning
g.setColor(Color.red);
g.fillOval(30 + col * 45, 10 + row * 45, 40, 40); // ghosts' body
g.setColor(Color.black);
g.fillOval(38 + col * 45, 20 + row * 45, 8, 8); // left eye
g.fillOval(53 + col * 45, 20 + row * 45, 8, 8); // right eye
g.drawLine(38 + col * 45, 37 + row * 45, 61 + col * 45, 37 + row * 45); // mouth
}
}
}
}
public void keyPressed(KeyEvent evt)
{
int value = evt.getKeyCode();
if(!lost && chez > 0)
switch(value)
{
case KeyEvent.VK_LEFT:
{
currentx--; // PacMan moves left
if(currentx == -1) // makes sure the PacMan can 'loop' around through 'portals'
currentx = 9;
direction = 180; //faces left
for(int a = 0; a < 6; a++)
moveGhosts(a);
} break;
case KeyEvent.VK_RIGHT:
{
currentx++; // PacMan moves right
if(currentx == 10) // makes sure the PacMan can 'loop' around through 'portals'
currentx = 0;
direction = 0; //faces right
for(int a = 0; a < 6; a++)
moveGhosts(a);
} break;
case KeyEvent.VK_UP:
{
currenty--; // PacMan moves up
if(currenty == -1) // makes sure the PacMan can 'loop' around through 'portals'
currenty = 9;
direction = 90; //faces up
for(int a = 0; a < 6; a++)
moveGhosts(a);
} break;
case KeyEvent.VK_DOWN:
{
currenty++; // PacMan moves down
if(currenty == 10) // makes sure the PacMan can 'loop' around through 'portals'
currenty = 0;
direction = 270; //faces down
for(int a = 0; a < 6; a++)
moveGhosts(a);
} break;
}
if(value == KeyEvent.VK_SPACE)
generateBoard(); // call on method to regenerate board
canvas.repaint(); // repaints the board
}
class ButtonPanel extends JPanel implements ActionListener
{
private JButton left, right, up, down, reset;
public ButtonPanel() // displays available buttons
{
left = new JButton("LEFT");
left.addActionListener(this);
this.add(left);
right = new JButton("RIGHT");
right.addActionListener(this);
this.add(right);
up = new JButton("UP");
up.addActionListener(this);
this.add(up);
down = new JButton("DOWN");
down.addActionListener(this);
this.add(down);
reset = new JButton("RESET");
reset.addActionListener(this);
this.add(reset);
}
public void actionPerformed(ActionEvent evt)
{
String command = evt.getActionCommand();
if(!lost && chez > 0)
{
if(command.equals("LEFT"))
{
currentx--; // PacMan moves left
if(currentx == -1) // makes sure the PacMan can 'loop' around through 'portals'
currentx = 9;
direction = 180; //faces left
for(int a = 0; a < 6; a++)
moveGhosts(a);
}
else if(command.equals("RIGHT"))
{
currentx++; // PacMan moves right
if(currentx == 10) // makes sure the PacMan can 'loop' around through 'portals'
currentx = 0;
direction = 0; //faces right
for(int a = 0; a < 6; a++)
moveGhosts(a);
}
else if(command.equals("UP"))
{
currenty--; // PacMan moves up
if(currenty == -1) // makes sure the PacMan can 'loop' around through 'portals'
currenty = 9;
direction = 90; //faces up
for(int a = 0; a < 6; a++)
moveGhosts(a);
}
else if(command.equals("DOWN"))
{
currenty++; // PacMan moves down
if(currenty == 10) // makes sure the PacMan can 'loop' around through 'portals'
currenty = 0;
direction = 270; //faces down
for(int a = 0; a < 6; a++)
moveGhosts(a);
}
}
if(command.equals("RESET"))
generateBoard(); // call on method to regenerate board
canvas.repaint(); // repaints the board
}
}
public void keyTyped(KeyEvent evt) {}
public void keyReleased(KeyEvent evt) {}
public void actionPerformed(ActionEvent evt) {}
}
Like they said in the comments because it is an applet you can not treat it as a regular java application. However, you can embed it into a browser or you can use the java tool appletviewer to run it without a browser. In your command line type in the following:
appletviewer [ options ] myApplet.html
Just put a myApplet.html in the folder:
<Html>
<Head>
<Title>Pac Man Applet</Title>
</Head>
<Body>
<Applet Code="MyApplet.class" width=200 Height=100>
</Applet>
</Body>
</Html>
The additional option is to create a stub application that will allow you to run an applet within a java application: Here is link to example. The example code is at bottom.