How should i best implement this?

[David McGratton]

Hi all,

This first post contains no code, just what i want to do and asking the best way to do this. I am familiar with swing however i havent used it much.
Future posts will be my code to be approved or critised.

It involves using timers within a game.

1) An item (eg loaf_of_bread) is on the screen
2) Player picks up item, item disappears , a timer is started eg 30 seconds.
3) After 30 seconds, the timer is destroyed and the item is remade and displayed.

My thoughts are, to create an "itemManager" class containing an array of "item". The player picking up the item calls "addItemToManager(variables go here)".
The item is added to itemManager array which initiates a timer which is used to regenerate the item on the screen, based on the variables.

I am after the most effecient method to do this.

Thankyou for reading the post,

Kindest Regards.

[Paul Clapham]

Then the best thing would be for you to list all the methods you have identified so far, and to evaluate each of them in terms of whatever "efficiency" means to you. You could post them here if you would like discussion about that process.

[David McGratton]

Hi Paul,

This is what i have so far for me to be advised on.

public class main {

	GameItemManager git = new GameItemManager();
	GameItem gi1 = new GameItem(5000, "item1");
	GameItem gi2 = new GameItem(8000, "item2");
	GameItem gi3 = new GameItem(20000, "item3");
    
    public static void main(String[] args) {
		 new main().run();
	}
    
	public void run() {		
		addItemsToManager();
		gameLoop();
	}
	    
	public void addItemsToManager() {
		git.addItem(gi1);
		git.addItem(gi2);
		git.addItem(gi3);
	}
	    
	public void gameLoop() {
		long startTime = System.currentTimeMillis();
		long currTime = startTime;

		while (!git.getItems().isEmpty()) {
			long elapsedTime = System.currentTimeMillis() - currTime;
			currTime += elapsedTime;
			
			update(elapsedTime);

			try {
				Thread.sleep(1000);
				gi1.setRemainingTime(gi1.getRemainingTime() - elapsedTime);
				gi2.setRemainingTime(gi2.getRemainingTime() - elapsedTime);
				gi3.setRemainingTime(gi3.getRemainingTime() - elapsedTime);
				//System.out.println(""+currTime);
			} catch (InterruptedException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	}
	    
	public void update(long elapsedTime) {
		git.update(elapsedTime);
	}
}

public class GameItem  {

    private long remainingTime;
    private boolean done;
    private String name;    
    
    public GameItem(long delay, String name) {
        this.setRemainingTime(delay);
        this.setName(name);
    }
    
    public void cancel() {
        done = true;
    }
    
    public boolean check(long elapsedTime, String name) {

    	System.out.println("Checking " + name);
        if (!done) {
        	setRemainingTime(getRemainingTime() - elapsedTime);
        	
        	if (getRemainingTime() <= 0) {
                cancel();
                System.out.println(name + " done");                
            }
        }

        return done;
    }

	public long getRemainingTime() {
		return remainingTime;
	}

	public void setRemainingTime(long remainingTime) {
		this.remainingTime = remainingTime;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

}

public class GameItemManager {

    private List items;
    
    public GameItemManager() {
    	System.out.println("GameItemManager Started");
        setItems(new ArrayList());
    }
    
    public void addItem(GameItem item) {
        getItems().add(item);
    }
    
    public void clear() {
        getItems().clear();
    }
    
    public void update(long elapsedTime) {

        System.out.println("Checking GameItemManager");
        List removeList = null;
        int size = getItems().size();
        
        for (int i=0; i<size; i++) {
            GameItem item = (GameItem)getItems().get(i);
            if (item.check(elapsedTime, item.getName())) {
                if (removeList == null) {
                    removeList = new ArrayList();
                }
                System.out.println(item.getName() + " removed");
                removeList.add(item);
            }
        }
        
        if (removeList != null) {
            getItems().removeAll(removeList);
        }
    }

	public List getItems() {
		return items;
	}

	public void setItems(List item) {
		this.items = item;
	}
}

Kindest Regards

[Rob Spoor]

When you need a timer in Swing, javax.swing.Timer is usually the way to go.