Where Should I Poll For Input?

[Time_Waave]

Hi, this is my first time posting and I am relatively inexperienced with programming computer games.  I have been learning in part from cokeandcode's Space Invaders tutorials.  I have lesson 104 downloaded and I am attempting to build something from scratch using it as a guideline.  This tutorial and my program use LWJGL.

My question is:  What is the best way to implement polling?  Where should I put it?
The parts of my code which relate to my question are as follows:

Interfaces:

• GameWindow -- describes the game window; tells Game when to act using a Callback interface; the game loop runs here.

Classes:

• Game (implements Callback) -- the main hook; tells stuff what to do.
• PlayerEntity (extends Entity) -- an entity I want to move when keys are pressed.

In the original source, cokeandcode implements the key polling in a very simple way:

Inside Game:

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GameWindow window = getGameWindow(); boolean leftPressed = window.isKeyPressed(KeyEvent.VK_LEFT); boolean rightPressed = window.isKeyPressed(KeyEvent.VK_RIGHT); boolean firePressed = window.isKeyPressed(KeyEvent.VK_SPACE);

Inside LWJGLGameWindow (implements GameWindow):

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public boolean isKeyPressed(int keyCode) {       switch(keyCode) {       case KeyEvent.VK_SPACE:          keyCode = Keyboard.KEY_SPACE;          break;       case KeyEvent.VK_LEFT:          keyCode = Keyboard.KEY_LEFT;          break;       case KeyEvent.VK_RIGHT:          keyCode = Keyboard.KEY_RIGHT;          break;       }       return org.lwjgl.input.Keyboard.isKeyDown(keyCode);    }

I know about Keyboard.next(), and I would like to use that.  Should I put it in GameWindow or in Game?  Or should I forgo LWJGL input and create a key listener?

[kappa]

I'd recommend you have a read of the LWJGL Basics Input Tutorial, it should give you a good idea on how to use input (Just read all 5 parts of the LWJGL Basics Tutorials for an overview of the LWJGL API).

[Time_Waave]

I read those, was just wondering where the best place in the code to implement the code.  I am guessing that it's not too important, so I came up with something I like.  Please tell me if there are any major problems with this:

• Each time through game loop, poll for keys.
• For every key event, add or remove the key's keycode from an ArrayList<Integer> (if the keycode is in the list, it implies that it is pressed)
• If I want to check for a key, use function isKeyPressed(keyCode), which use ArrayList.contains() to see if the key is held down