I need help to draw an image and move it plz plz : )

Question

Ok, so I have this whole code and I understand most of it but not all of it but I'm trying to make image "drop.gif" to move down the right side of the window. For each shot that is taken the image moves down ever so much and if the image hits the Entity ship "background" than notify death. PLease anyone help me !
there are 7 classes but here is the main ...
package spaceinvaderss;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.image.BufferStrategy;
import java.util.ArrayList;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Main extends Canvas {
/*A Canvas component represents a blank rectangular area of the screen onto which the application can draw or from which the application can trap input events from the user.
An application must subclass the Canvas class in order to get useful functionality such as creating a custom component.
The paint method must be overridden in order to perform custom graphics on the canvas.*/
/** The stragey that allows us to use accelerate page flipping.*/
private BufferStrategy strategy;
/** True if the game is currently "running", i.e. the game loop is looping */
private boolean gameRunning = true;
/** The list of all the entities that exist in our game */
private ArrayList entities = new ArrayList();
/** The list of entities that need to be removed from the game this loop */
private ArrayList removeList = new ArrayList();
/** The entity representing the player */
private Entity ship;
/** The entity representing the alien */
private Entity alien;
/** The speed at which the player's ship should move (pixels/sec) */
private double moveSpeed = 600;
/** The time at which last fired a shot */
private long lastFire = 0;
/** The interval between our players shot (ms) */
private long firingInterval = 400;
/** timer */
private long time = 0;
/** The number of aliens left on the screen */
private int alienCount;
/** The message to display which waiting for a key press */
private String message = "";
/** True if we're holding up game play until a key has been pressed */
private boolean waitingForKeyPress = true;
/** True if the left cursor key is currently pressed */
private boolean leftPressed = false;
/** True if the right cursor key is currently pressed */
private boolean rightPressed = false;
/** True if we are firing */
private boolean firePressed = false;
/** True if game logic needs to be applied this loop, normally as a result of a game event */
private boolean logicRequiredThisLoop = false;
private static Image drop;
/** The constant for the width*/
private int DOMAIN = 800;
/** The constant fot the length*/
private int RANGE = 950;
/** The constant for the number of rows of aliens */
private int numbaofrows = 8;
/** The constant for the number of aliens per row */
private int aliensperrow = 12;
/** The constant for the percent of which the speed increases*/
private double speedincrease = 1.02;
/** Starts the variable that counts the shots*/
private int shotsfired = 0;
/** Construct our game and set it running.*/
public Main() {
// Creates a frame to contain Main.
JFrame container = new JFrame("SPACE INVADERS !!! WOOT !!! WOOT !!!");
// Gets a hold of the content of the frame and sets up the resolution of the game
// Names the inside of the "container" as panel.
JPanel panel = (JPanel) container.getContentPane();
// Stes the demensions of the panel.
panel.setPreferredSize(new Dimension(DOMAIN,RANGE));
//Sets the layout as nothing which overrides any automatic properties.
panel.setLayout(null);
// Sets up our canvas size and puts it into the content of the frame
setBounds(0, 0, DOMAIN, RANGE);
panel.add(this);
// Tell AWT not to bother repainting our canvas since we're
// going to do that our self in accelerated mode.
setIgnoreRepaint(true);
// Actually sizes the window approximately.
container.pack();
// Makes it so that the window can't be resized.
container.setResizable(false);
// Makes the window visible.
container.setVisible(true);
// Add a listener to respond to the user pressing the x.
// End the program when the window is closed.
container.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
// add a key input system (defined below) to our canvas
// so we can respond to key pressed
addKeyListener(new KeyInputHandler());
// request the focus so key events come to us
requestFocus();
// Create the buffering strategy which will allow AWT
// to manage our accelerated graphics.
createBufferStrategy(2);
strategy = getBufferStrategy();
// initialise the entities in our game so there's something
// to see at startup
initEntities();
time = System.currentTimeMillis();
* Start a fresh game, this should clear out any old data and
* create a new set.
private void startGame() {
// clear out any existing entities and intialise a new set
entities.clear();
initEntities();
// blank out any keyboard settings we might currently have
leftPressed = false;
rightPressed = false;
firePressed = false;
* Initialise the starting state of the entities (ship and aliens). Each
* entitiy will be added to the overall list of entities in the game.
private void initEntities() {
ClassLoader cloader = Main.class.getClassLoader();
drop = Toolkit.getDefaultToolkit().getImage(cloader.getResource("drop.gif"));
prepareImage(drop, this);
// create the player ship and place it in the center of the screen
ship = new ShipEntity(this,"background.gif", 0, (RANGE - 75));
entities.add(ship);
ship = new ShipEntity(this,"ship.gif", (DOMAIN / 2) - 0, (RANGE - 50));
entities.add(ship);
// create a block of aliens
alienCount = 0;
for (int row = 0; row < numbaofrows; row++) {
for (int x = 0; x < aliensperrow; x++) {
alien = new AlienEntity(this,"alien.gif", 100 + (x*50),(50)+row*30);
entities.add(alien);
alienCount++;
* Notification from a game entity that the logic of the game
* should be run at the next opportunity (normally as a result of some
* game event)
public void updateLogic() {
logicRequiredThisLoop = true;
* Remove an entity from the game. The entity removed will
* no longer move or be drawn.
* Remove the entity
public void removeEntity(Entity entity) {
removeList.add(entity);
/**Notify that the player has died.*/
public void notifyDeath() {
message = "Oh no! The aliens win, wanna try again?";
waitingForKeyPress = true;
/** Notification that the player has won since all the aliensare dead.*/
public void notifyWin() {
long time2;
time2 = (System.currentTimeMillis() - time) / 1000;
int acuracy = 1000*(aliensperrow*numbaofrows)/shotsfired;
message = "Congradulations! You win! Your time was: " + time2 + " seconds. Your acuracy was " + acuracy + "%.";
waitingForKeyPress = true;
/**Notification that an alien has been killed*/
public void notifyAlienKilled() {
// reduce the alient count, if there are none left, the player has won!
alienCount--;
if (alienCount == 0) {
notifyWin();
// if there are still some aliens left then they all need to get faster, so
// speed up all the existing aliens
for (int i = 0; i < entities.size(); i++) {
Entity entity = (Entity) entities.get(i);
if (entity instanceof AlienEntity) {
// speed up every time the aliens move down
entity.setHorizontalMovement(entity.getHorizontalMovement() * speedincrease);
/**Attempt to fire a shot from the player. Its called "try" since we must first
* check that the player can fire at this point, i.e. has he/she waited long
* enough between shots.*/
public void tryToFire() {
// check that we have been waiting long enough to fire
if (System.currentTimeMillis() - lastFire < firingInterval) {
return;
// if we waited long enough, create the shot entity, and record the time.
lastFire = System.currentTimeMillis();
ShotEntity shot = new ShotEntity(this, "bullet.gif", ship.getX() + 27, ship.getY() - 30);
entities.add(shot);
* The main game loop. This loop is running during all game
* play as is responsible for the following activities:
* - Working out the speed of the game loop to update moves
* - Moving the game entities
* - Drawing the screen contents (entities, text)
* - Updating game events
* - Checking Input
public void gameLoop() {
long lastLoopTime = System.currentTimeMillis();
// Keep looping around till the game ends.
while (gameRunning) {
// Work out how long its been since the last update, this
// will be used to calculate how far the entities should
// move this loop.
long delta = System.currentTimeMillis() - lastLoopTime;
lastLoopTime = System.currentTimeMillis();
// Get hold of a graphics context for the accelerated
// surface and black it out.
Graphics2D g = (Graphics2D) strategy.getDrawGraphics();
g.setColor(Color.black);
g.fillRect(0, 0, DOMAIN, RANGE);
// Cycle around asking for each entity to move itself.
if (!waitingForKeyPress) {
for (int i = 0; i < entities.size(); i++) {
Entity entity = (Entity) entities.get(i);
entity.move(delta);
// cycle round drawing all the entities we have in the game
for (int i = 0; i < entities.size(); i++) {
Entity entity = (Entity) entities.get(i);
entity.draw(g);
// brute force collisions, compare every entity against
// every other entity. If any of them collide notify
// both entities that the collision has occured
for (int p = 0; p < entities.size(); p++) {
for (int s = p + 1; s < entities.size(); s++) {
Entity me = (Entity) entities.get(p);
Entity him = (Entity) entities.get(s);
if (me.collidesWith(him)) {
me.collidedWith(him);
him.collidedWith(me);
// remove any entity that has been marked for clear up
entities.removeAll(removeList);
removeList.clear();
// if a game event has indicated that game logic should
// be resolved, cycle round every entity requesting that
// their personal logic should be considered.
if (logicRequiredThisLoop) {
for (int i = 0; i < entities.size(); i++) {
Entity entity = (Entity) entities.get(i);
entity.doLogic();
logicRequiredThisLoop = false;
// if we're waiting for an "any key" press then draw the
// current message
if (waitingForKeyPress) {
g.setColor(Color.green);
g.drawString(message,(DOMAIN-g.getFontMetrics().stringWidth(message)) / 2, 250);
g.drawString("TO PLAY, PRESS ANY KEY : )", (DOMAIN-g.getFontMetrics().stringWidth("TO PLAY, PRESS ANY KEY : )")) / 2, 40);
// Clear up the graphics.
g.dispose();
// Flip the buffer over.
strategy.show();
// resolve the movement of the ship. First assume the ship
// isn't moving. If either cursor key is pressed then
// update the movement appropraitely
ship.setHorizontalMovement(0);
if ((leftPressed) && (!rightPressed)) {
ship.setHorizontalMovement(-moveSpeed);
} else if ((rightPressed) && (!leftPressed)) {
ship.setHorizontalMovement(moveSpeed);
// if we're pressing fire, attempt to fire
if (firePressed) {
shotsfired++;
tryToFire();
// finally pause for a bit. Note: this should run us at about
// 100 fps but on windows this might vary each loop due to
// a bad implementation of timer
try { Thread.sleep(10); } catch (Exception e) {}
* A class to handle keyboard input from the user. The class
* handles both dynamic input during game play, i.e. left/right
* and shoot, and more static type input (i.e. press any key to
* continue)
* This has been implemented as an inner class more through
* habbit then anything else. Its perfectly normal to implement
* this as seperate class if slight less convienient.
private class KeyInputHandler extends KeyAdapter {
/** The number of key presses we've had while waiting for an "any key" press */
private int pressCount = 1;
* Notification from AWT that a key has been pressed. Note that
* a key being pressed is equal to being pushed down but NOT
* released. Thats where keyTyped() comes in.
* @param e The details of the key that was pressed
public void keyPressed(KeyEvent e) {
// if we're waiting for an "any key" typed then we don't
// want to do anything with just a "press"
if (waitingForKeyPress) {
return;
if (e.getKeyCode() == KeyEvent.VK_LEFT) {
leftPressed = true;
if (e.getKeyCode() == KeyEvent.VK_RIGHT) {
rightPressed = true;
if (e.getKeyCode() == KeyEvent.VK_SPACE) {
firePressed = true;
* Notification from AWT that a key has been released.
* @param e The details of the key that was released
public void keyReleased(KeyEvent e) {
// if we're waiting for an "any key" typed then we don't
// want to do anything with just a "released"
if (waitingForKeyPress) {
return;
if (e.getKeyCode() == KeyEvent.VK_LEFT) {
leftPressed = false;
if (e.getKeyCode() == KeyEvent.VK_RIGHT) {
rightPressed = false;
if (e.getKeyCode() == KeyEvent.VK_SPACE) {
firePressed = false;
* Notification from AWT that a key has been typed. Note that
* typing a key means to both press and then release it.
* @param e The details of the key that was typed.
public void keyTyped(KeyEvent e) {
// if we're waiting for a "any key" type then
// check if we've recieved any recently. We may
// have had a keyType() event from the user releasing
// the shoot or move keys, hence the use of the "pressCount"
// counter.
if (waitingForKeyPress) {
if (pressCount == 1) {
// since we've now recieved our key typed
// event we can mark it as such and start
// our new game
waitingForKeyPress = false;
startGame();
pressCount = 0;
} else {
pressCount++;
// if we hit escape, then quit the game
if (e.getKeyChar() == 27) {
System.exit(0);
* The entry point into the game. We'll simply create an
* instance of class which will start the display and game
* loop.
* @param argv The arguments that are passed into our game
public static void main(String argv[]) {
Main g = new Main();
// Starts the main game loop, this method will not return until the game has finished running. Hence we are
// using the actual main thread to run the game.
g.gameLoop();
}                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           

Answer 1

Ap_Compsci_student_13 wrote:
ok sorry but doesn't sscce say to post the whole code?the first S is Short, and yes, it needs to be all the code needed to illustrate the problem and let use reproduce it. If you were developing a new Web framework, your example might be short, but for a student game it's very long.