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performance loading images game class

I'm trying to decide between several ways of drawing images for objects in a game.
I want objects to have their own draw() method, but I'm afraid that I may cause unnecessary copies of the image or some other drop in efficiency, noticeable or not.
The first way loads the BufferedImages when the level starts.
public class levelone{
BufferedImage imageguy;
public void draw(Graphics2d g){
g.drawImage(imageguy, null, guy.getx(), guy.gety());
}
}
The second way loads the image in the guy.class and draws it from there with just a guy.draw(g); call in the levelone.class.
The third way loads the image in levelone.class and draws it from guy.class with just guy.draw(imageguy, g); in levelone.class.
Help me understand the best way to go about this please. If it's not clear what I'm asking, do tell and I'll try to make it more comprehensible.

This is more of a design question. For a start, this:
... some other drop in efficiency, noticeable or not.
... is not a very healthy or productive way of thinking. If it's not noticeable, it's not worth worrying about. Otherwise you might as well be writing your game in assembly code if you are going to obsess over every clock cycle.
But there might be broader scale design-level scalability concerns here of note.
It's worth noting that coupling rendering/drawing logic with a high-level class can become a maintenance burden. It depends on the scope of your project, but if it's a rather large project, you'll have a lot more breathing room if you separate the drawing/rendering logic from your game logic. Then you can focus your full attention on just what a "Monster" or an "Item" or something of that sort needs to do from a game design standpoint without worrying about how it'll be drawn. The drawing is done elsewhere.
But if we assume you want to have the drawing logic inside these objects anyway, then it seems like your question ultimately boils down to where you want to store some image buffers for graphics related to the objects in your game.
And the short answer is, "it depends". What assumptions do you feel confident making? For example, in your posted code:
public void draw(Graphics2d g){
g.drawImage(imageguy, null, guy.getx(), guy.gety());
}
... this seems kind of ridiculous if all you'll ever do is blit the object image to the graphic. If all you're ever going to do is blit the item's image to the graphic, then you might as well eliminate the draw method outright, expose a public accessor to the image, and let one central place handle the responsibility of blitting those images at the right time and place.
And at that point, if all you're doing is storing images and exposing accessors to them in your objects, then you might as well let the outside world concern itself with loading/storing those images and blitting them, leaving your objects clean and devoid of drawing logic outright. That'll also give you the most flexibility to optimize when and how things are drawn without intrusively touching all your objects.
But are you always going to just blit images from an object? Will there ever be a case where an object in your game might draw additional things, shapes, text, etc? If so, you might want to keep the draw method.
So the ultimate question to me is, do you really want to do drawing inside your objects or not?
If not, then you'll have the most flexibility to optimize to your heart's content, since you can leave the responsibility of most efficiently loading and storing and drawing graphics to a central render engine instead of spreading that responsibility over every object in your game (and potentially having to change all of them if you ever want to do things differently).
if you do want this, then you might as well fully encapsulate all the details involved with rendering an object inside an object, including keeping whatever assets it needs to do that so that the outside world doesn't have to bother with it and can just call 'draw' and pass in a drawing target (Graphics2D, e.g.).
So I would suggest that maybe none of your proposals may be ideal. But if there's one option that might be bad, I'd say it's your third. That is:
The third way loads the image in levelone.class and draws it from
guy.class with just guy.draw(imageguy, g); in levelone.class.
The problem here is that you're kind of getting the worst of both worlds. You're leaking the drawing details of this 'guy' to the outside world, but the outside world still has to depend on the 'guy' to do the drawing by passing those drawing details back in. If nothing else, you want to really give either the guy or the outside world the primary responsibility here, with the latter being more flexible, but the former being more encapsulated. When the outside world has to pass a guy's image back to the guy for the guy to draw, then you get neither of these benefits. If you really want a guy to "draw himself", then you generally want to be able to do it without too much help from the outside. Give one entity the firm responsibility instead of spreading it across multiple.
About unnecessary copies of the same image, that's easily solved no matter what you do with a central image cache. An easy way is just use a map. When loading an image, search the map for the path. If it already exists, return a reference to an already-loaded image. Otherwise load the image and insert that the path/image as a key/value pair to the map.

Java 2D Game Performance with Java Swing Timer

I am developing a shoot'em up type video game using Java Swing and I'm using a Java Swing Timer to control all of the screen updating. The main screen uses a BorderLayout, and I perform my graphics on a Panel contained within the BorderLayout, and use the AWT Graphics calls to draw.
Now as my game progresses, I would like to speed up the movement of my screen objects (ships), yet I still want them to smoothly cross the screen. I thought I could speeed things up by dropping the timeout value for the Java Swing Timer, down to around 5ms. But, I've noticed when I set it to anything less than 15ms, there does not seem to be much difference. Once you cross that threshold, there is almost no noticeable difference in performance. -Why is that?-
Another option would be to increase how many pixels each ship moves per update, but anything beyond 3 or 4 pixels, and things start to look jumpy.
Any ideas? And really want to keep the game in Swing, would prefer at this point not porting to a 3rd party library.
Thanks.

In all likelihood, this isn't a software issue, nor is it fixable with software. Your screen probably only refreshes about 60 times a second, meaning that the frames are only drawn 60 times per second, or once every (approximately) 16 milliseconds. Since this is a hardware barrier, there's no way to get it to update faster with software. You can probably count on your users only having 60Hz monitors, too, so it's more worthwhile to look into other solutions.
One solution that pops to mind is adding in motion blur, to make it seem like the ships are moving faster when they really aren't. It'll allow you to 'jump' a greater distance before it looks jumpy, since the blur tricks the eye into thinking it's going really fast instead of hopping across the screen. Unfortunately, the only things that I see to do motion blur are third-party libraries, though you may have better luck Googling.

I advise you that you change your Swing engine for JavaFX (at least), a technology with better performance and more tools to your disposal. Swing nowadays is considered a dead technology, as well as with the AWT before it. A great place to study and start JavaFX would be this one:
http://docs.oracle.com/javase/8/javase-clienttechnologies.htm
The ideal for the development of games, would be to use a library prepared for it, such as libGDX:
http://libgdx.badlogicgames.com/
But if your desire is to create a game in Swing, who am I to judge? Sometimes it is good to see old things. I myself still like Swing, even being obsolete compared to other things.
I think you may be implementing a wrong gameloop. Swing Timer does not really seem like a good way to update game logic. Even with different settings between different computers, is generally practical and easy to implement a gameloop to work properly, especially for the correct movement of the characters.
You see, a gameloop is the heart of a game, and needs to be implemented straight otherwise the game is developed wrong and with several limitations. Generally, in gameloop we have to take into account the desired FPS. Among game updates, we must take the time elapsed between the last update and the current update, so-called delta by many developers. You will find many materials about it on the internet, which I recommend:
http://dewitters.koonsolo.com/gameloop.html
http://www.java-gaming.org/index.php?topic=21919.0
https://www.youtube.com/watch?v=9dzhgsVaiSo
The past links will help you for sure, but if you want more about it, I recommend that you take a look at this book:
http://www.brackeen.com/javagamebook/
Even the material being old (as Swing is) you'll find details of how to implement a good gameloop with a keyboard and mouse iinput system, sound, the use of the best possible performance swing has to offer, among other cool things. And one more thing... To give you a better result with respect to the movement of the characters, I advice you to use position variables (X and Y) with decimal types such as float or double.
I hope you can do what you want. Good luck!

Bx2D body Sprite synch

seeing as how box2D bodies cannot be resized, I have a problem with bodies and my animated sprites.
here's the situation which I have no doubt is not unique:
my sprite's dimensions slightly change during different motions like attacking, walking, jumping. seeing as how I was about to use box2D body for collision detection this can cause quite a problem.
so far I thought of 3 ways to solve this issue.
1- not use box2d bodies for collision detection , just use them for object's physical behavior
2- delete and recreate body before each render. or on animation change.
3- trying to recheck the collision on bodies to see if it actually collides with the sprite itself. then act.
and here's the problem I have with each of these solutions.
1- this way makes using box2d as a whole seem rather absurd, also I'll be using not one, but two world logic and trying to keep them in sync. seems like a big headache.
2- this doesn't look very optimized, also I doubt I can just make objects pop in and out of existence in a physics world without side effects.
3- I'm not sure how or even if this can be done, actually this option is the one I require more advice on. will this cause any difficulties in the long run, or cause conflicts in physics.
please let me know if there is a efficient way to solve this , or if any of the above solutions is worth working on.
my thanks
Edit:
It was more of a general question since I still don't have proper graphics for the game I'm writing, but here's my practice material:
walking waiting (standing)
attacking

A body can have multiple fixtures, so you can add all fixtures for each state to the body. If you make them zero density it should not affect the physics behavior of the body. Keep in mind though, that at least one fixture on the body should be non-zero density - you could make one fixture to act as the main fixture, which has density to give the body some mass.
If you just need to detect when these fixtures are touching something, you could make them sensor fixtures, and use your contact listener to keep track of what other things they are currently touching. The contact listener would give you callbacks about all of the fixtures regardless of which state your character is in, and for each state you would keep a list of which things the fixtures for that state are touching.
If you need the fixtures to have physical interaction but only when their state is active, you could do the above but also in BeginContact you would do contact->setEnabled(false) if the contact is for a fixture that is not currently in active state.

How to structure simple Android apps

I've run into an organizational problem with an application I am working on, on the Android platform. The application uses sensors as input and OpenGL as output.
The traditional method is something
like organizing the project into an
MVC where I have the main activity
class load an OpenGL view and a
sensor handling class and will then
probably register some callbacks or
possibly do it on a clock.
The sloppy alternative is having a single class that implements GLSurfaceView and SensorEventListener and then offload the logic into other classes.
Assume very simple drawing code and somewhat complex control system code that will attempt to refresh at 60ish Hz. I am looking for performance, maintainability and easy of development implications, so any and all input is valuable. Also I am a complete novice when it comes to Android or mobile development so if you can show me the light with a third alternative that'd be great too.

Sometimes, over-planning things can be a waste of time.
Different games use different approaches, you'll want to take a look at the replica island's dev blog and code for various hints on how to organize your code using a GLSurfaceView. http://replicaisland.net/
I use your latter approach, but it's not as sloppy as you make it seem.
You don't really need any logic code in your GLSurfaceView, just calls to your classes when certain events happen. (onDraw, onTouch, onKey, etc)
Not sure what's sloppy about this, I maintain my logic in their proper classes.
For example, in my onDrawFrame() I simply do MyAreaManager.draw(gl)
The MyAreaManager class would maintain it's own logic and know what to draw.
As for the clock, you'll most likely want two threads. One for rendering (the GLSurfaceView thread) and one for game logic that runs at a certain logic frame rate.
The logic frame, would simply change the state of the canvas objects and the draw frame would simply draw them as fast as possible.
This way you render as fast as possible and still maintain a steady logic frame rate.

Pacman in Java questions

For my university assignment I have to make a networkable version of pacman. I thought I would best approach this problem with making a local copy of pacman first and then extend this functionality for network play.
I would have to say that I am relatively new to java GUI development and utilizing such features within java.
http://www.planetalia.com/cursos/Java-Invaders/
http://javaboutique.internet.com/PacMan/source.html
I have started following the above links with regards to game development within java and an example of the pacman game.
I decided to represent the maze as an int array with different values meaning different things. However when the paint method inside the main game loop is run i am redrawing the whole maze with this method.
for (int i : theGame.getMaze())
{
if (i == 4)
{
g.setColor(mazeWallColour);
g.fillRect(curX, curY, cellSize, cellSize);
curX += 25;
}
else
{
curX += cellSize;
}
index++;
// Move to new row
if (index == 25)
{
index = 0;
curX = 10;
curY += cellSize;
}
}
However this is providing me with less then 1fps. Although i've noticed the example linked above uses a similar way of redrawing each time the paint method is called and i believe does this on a image that is not viewable (kinda like double buffering [I've used a BufferStrategy like the first link explains]) What would be a better way to redraw the maze?
Any pointers/advice with this would be useful.
Thank you for your time.
http://pastebin.com/m25052d5a - for the main game class.
Edit: I have just noticed something very weird happening after trying to see what code was taking so long to execute.
In the paintClear(Graphics g) method i have added
ocean = sprites.getSprite("oceano.gif");
g.setPaint(new TexturePaint(ocean, new Rectangle(0,t,ocean.getWidth(),ocean.getHeight())));
g.fillRect(10, 10,getWidth() - 20,getHeight() - 110);
which made the whole thing run smoothly - however when i removed these lines the whole thing slowed down? What could have caused this?
Updated code

First off, I'd recommend that you use named constants rather than having random magic numbers in your code and consider using enums for your cell types. While it won't make your code run any faster, it certainly will make it easier to understand. Also, 'i' is normally used as a counter, not for a return value. You should probably call it cellType or something similar. I'd also recommend that you use a 2D array for your stage map since it makes a number of things easier, both logistically and conceptually.
That said, here are a few things to try:
Pull the setColor() out of the loop and do it once. The compiler might be able to do loop-invariant hoisting and thus do this for you (and probably will), but conceptually, you should probably do this anyway since it appears you want all of your walls to be one color anyway.
Try calling drawRect() instead of fillRect() and see if that draws faster. I don't think it will, but it is worth a shot, even if it looks uglier. Similarly, you can try creating an Image and then drawing that. This has the advantage that it is really easy to tell your Graphics object to implement a transform on your image. Also, consider taking this out completely and make sure that it is being a significant performance hit.
Also, normally you don't need to ask for the parent for its Graphics object and implement painting directly on it. Rather, you should override its paintComponent() method and just utilize the Graphics given to you (possibly calling helper methods as you do). Swing components are double-buffered by default, so you don't need to implement that yourself; just let the swing object do its job and let you know when to paint.
Also, you end up repainting the entire screen, which is something of overkill. If you call repaint(Rectangle), Swing can choose to redraw only the sections of your board that are explicitly marked dirty. When you update one of your sprites, call repaint(r) only on the area of the sprite's old and new locations. When you complete a level and need a new board, then you can call repaint() (without parameters) to redraw the entire map.
You should also look at Sun's tutorial to get some tips for efficiency in Swing.

I still consider myself a beginner with Java, but I recently developed a Frogger-esque game with dynamic map and editor using some of the techniques you've mentioned, and I'm only too happy to provide some help.
As mentioned, enum's are the way to go. I set my map up as a 2-dimensional array and set an enum for each different type, writing a method inside my map class to take in one image and divide each square in the map to each value in my enum.
A tutorial that helped me with mapping can be found on Coke and Code. All the source code is there if you need a hand with any of it, although you do seem to have a decent grasp of what you're doing. If you still need help I could always drag out some source code.

It looks like your call to Thread.sleep doesn't do what you intended, but I don't think it's the source of your trouble. You have:
Thread.sleep(Math.max(0, startTime - System.currentTimeMillis()));
startTime will always be less than System.currentTimeMillis(), so startTime - System.currentTimeMillis() will always be negative and thus your sleep will always be for 0 milliseconds. It's different from the example you showed because the example increments startTime by 40 milliseconds before doing the calculation. It is calculating how long to sleep for to pad out the drawing time to 40 milliseconds.
Anyway, back to your problem. I'd recommend measurement to figure out where your time is being spent. There's no point optimising until you know what's slow. You already know how to use System.currentTimeMillis(). Try using that to measure where all the time goes. Is it all spent drawing the walls?
EDIT - I see this got marked as accepted, so should I infer that the problem went away when you fixed the sleep time? I don't have a lot of Java GUI experience, but I can speculate that perhaps your code was starving out other important threads. By setting your thread to have maximum priority and only ever calling sleep(0), you pretty much guarantee that no other thread in your process can do anything. Here's a post from Raymond Chen's blog that explains why.

The code you listed above can't be the source of the 1fps problem... I have code doing far more than this that runs far faster.
Can you benchmark that code and make sure it's the root of the problem?

I'm no game developer, but that framerate seems very slow.
I'm not quite sure how your code is working, but one possibility for improving rendering performance would be to find those parts of the display that don't change much (such as the walls of the maze) and avoid re-creating them for each frame.
Create a BufferedImage containing the constant elements (maze?, background) and then re-draw it first for each frame. On top of this Buffered image, draw the variable elements (PacMan, ghosts, dots, etc).
This technique, along with many other Java2D performance tips, is discussed in Romain Guy's excellent book Filthy Rich Clients.

Just so you don't worry that it's Java, I worked on a Spectrum Analyzer (Like an o-scope) where the entire GUI portion(the trace, menus, button & wheel handling) was done in Java. When I got there it was getting 1fps, when I left it was 12-20. That had a lot of processing going on and was running on a very slow processor.
Look at only updating parts of the GUI that you need to update. Often you can redraw the entire screen but just set a clipping region to the part that is truly updated.
Be careful about inner loops--they are The Speed Killer.
Try to avoid allocating and freeing huge numbers of objects. I'm not saying don't use objects, I'm saying don't create one for each pixel :)
Good luck

Wow, that's a pretty tough problem to give someone just learning Java.
My advice? Think in terms of objects. Can you write something WITHOUT a user interface that mimics the behavior of the game itself? Once you get that working, you can concentrate on the special problems of the user interface. Yes, start with a local version before the networked piece.
I'm not a gamer. I wonder what Java2D API would offer to make your life better?
How much time do you have to finish it?

This might sound obvious but your performance problem is because you are redrawing the entire maze, which doesn't need to be done, instead you need to redraw only changed parts of your maze.
The way I've approached this issue before is by seperating the updating of the maze from the actual redrawing into different threads (kind of like a threaded MVC). Every time you change a cell in your maze you would mark it as "dirty", your redraw thread will check every now and then to redraw only the dirty cells.
Sorry for the extremly generic advice

Java/Swing double-buffers by default. If you're using Swing, you don't need to double-buffer separately, like other answers suggest.
I agree with Allain, that the code you listed can't be the cause of 1fps. I've written highly inefficient Java/Swing animation code that runs much faster than you describe. Do some more testing to narrow down the cause of the slowness.

If possible, you should keep an image of the maze, and draw it in one library call. It probably doesn't need to be full resolution, either -- if you want a blocky, 8-bit feel, I expect the graphics library will be more than happy to oblige 8^)
Also, as others have mentioned, you can save time by redrawing only those parts of the screen that need updating. This can be annoying to implement, but it may allow you to significantly improve your frame rate. Be sure to do some experiments to make sure this is the case before exerting the required effort!