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The compiler is not recognizing my input for .getPoint

We areto create a plane and have its speed increase 5mph every time the user inputs the up arrow key and decrease 9mph when hitting the down key. It is supposed it report this back to the user in output box whenever whichever action is completed. How do I set it up so that the keylistener will tell the user that they have pressed the up key? Im still working on this so sorry if it is messy.
private class PolygonPanel implements MouseListener, MouseMotionListener, KeyListener
{
public void mousePressed(MouseEvent event){} //unused event
public void mouseDragged(MouseEvent event){} //unused event
public void keyReleased(KeyEvent event){}
public void keyTyped(KeyEvent event){}
//public void keyPressed(KeyEvent event){}
public void keyPressed(KeyEvent event) {
Integer planespeed=event.getKeyCode();
if (event.getKeyCode() == KeyEvent.VK_RIGHT)
{
//Not gonna use this.
}
if (event.getKeyCode() == 39)//KeyEvent.VK_LEFT
{
System.out.print("This key is up");
}
if (event.getKeyCode() == KeyEvent.VK_UP)
{
System.out.print("This key has been pressed");
//speed=planespeed+5;
}
if (event.getKeyCode() == KeyEvent.VK_DOWN)
{
//speed=planespeed-9;
}
repaint();
}

A frame doesn't detect keybaord input if it is not focused on. Therefore, in order to retrieve keyboard input of any kind, you would have to set your frame to be focusable, using a line such as setFocusable(true); in your constructor. You might also have to add a line such as addKeyListener(new PolygonPanel()); so the listener is registered at all.

How do I respond to two different KeyEvents Simultaneously?

So I am basically creating a platformer game in java. Here is a simple question. Can I respond to two different KeyEvents simultaneously? For example, I am pressing the right arrow key and my player is moving right. Now, I want my player to jump but keep moving right. For this I would need to respond to two different KeyEvents simultaneously. How do I achieve this? I have not tried any code yet because I don't know where to start with. Thank you for the answer in advance.

You can use seperate "KeyDown" and "KeyUp"-events and set state values for your player.
You need a State-Machine for your player.
public class KeyboardListener extends JFrame implements KeyListener {
public KeyboardListener() {
addKeyListener(this);
}
#Override
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == KeyEvent.VK_RIGHT) {
System.out.println("Right key pressed");
}
if (e.getKeyCode() == KeyEvent.VK_LEFT) {
System.out.println("Left key pressed");
}
}
#Override
public void keyReleased(KeyEvent e) {
if (e.getKeyCode() == KeyEvent.VK_RIGHT) {
System.out.println("Right key Released");
}
if (e.getKeyCode() == KeyEvent.VK_LEFT) {
System.out.println("Left key Released");
}
}
public static void main(String[] args) {
new KeyboardListener();
}
}
Use the keyPressed and keyReleased-EventHandlers from the KeyListener Interface and save your current player states like walking, jumping, walk_left, walk_right etc as booleans for example.
In your mainloop you can check what state your player is in and change its coordinates. Like:
if(player.left) { player.x += speed } //etc.

You might want to use Threads and then add pressed keys to a list the player physics class.
public class KeysListener implements KeyListener
...
//FIRST THREAD
new Thread(new Runnable() {
#Override
public void run() {
public void keyEvent(KeyEvent e) {
int key = e.getKeyCode();
//TODO ADD KEY TO A LIST IN THE CLASS THAT HANDLES YOUR PHYSYICS
}
}
}).start();
//SECOND THREAD
new Thread(new Runnable() {
#Override
public void run() {
public void keyEvent(KeyEvent e) {
int key = e.getKeyCode();
//TODO ADD KEY TO A LIST IN THE CLASS THAT HANDLES YOUR PHYSICS
}
}
}).start();
...
}
Add as many threads as the number of simultaneous keys you require.

mouseEntered can't catch fast mouse movement

I have an array of JToggleButtons that make a calendar selector of sorts. I have implemented a way to drag the mouse over the buttons to toggle multiple days without having to stop and click each one, and it works great for slower mouse movements:
JToggleButton[] buttons = getCalendarDayButtonArray(); //arbitrary instantiation
for (int d = 0; d < 31; d++) {
final JToggleButton b = new JToggleButton(day);
buttons[d] = b;
buttons[d].addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {//do stuff...}
}
buttons[d].addMouseListener(new MouseAdapter() {
public void mouseEntered(MouseEvent e) {
if (e.getModifiers() == MouseEvent.BUTTON1_MASK) {
b.doClick();
}
}
public void mousePressed(MouseEvent e) {
if (e.getModifiers() == MouseEvent.BUTTON1_MASK) {
b.doClick();
}
}
});
}
However, this doesn't work entirely for quick movements. I am not sure whether it is a problem with the polling rate of the mouse, or a result of any lag on the computer itself, but it seems that the mouse skips over some buttons entirely and as a result the mouseEntered method is not invoked for these buttons. Is there a workaround that doesn't involve the user simply moving the mouse slowly? Thanks in advance!

How to Override Key Repeat - KeyListener

I have a Graphics project that contains KeyListener, where the arrow keys and space bar controls the movement of a spaceship. However, when a key is held down, it registers the next key presses after a delay after the first. I would like for a held down key to register continuously.
I suspect that this is due to my computer's setting for key repeat delay, so is there any way to temporarily override this in my program, or a workaround for it?
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == 38) { //Up Arrow
currentLevel.moveSpiffUp();
} else if (e.getKeyCode() == 40) { //Down Arrow
currentLevel.moveSpiffDown();
} else if (e.getKeyCode() == 32 && !currentLevel.getFrapRayActive()) {
currentLevel.shoot();
}
repaint();
}

I would suggest using key press and key released
public class MyKeyListener implements KeyListener {
//class gets the input from the player
public void keyTyped(KeyEvent e) {
}
#Override
public void keyPressed(KeyEvent e) {
if(KeyEvent.getKeyText(e.getKeyCode()).equals("Left")) {
//left arrow key
} else if (KeyEvent.getKeyText(e.getKeyCode()).equals("Right")) {
//right arrow key
}
}
public void keyReleased(KeyEvent e) {
if(KeyEvent.getKeyText(e.getKeyCode()).equals("Left"){
//left key released
}
if(KeyEvent.getKeyText(e.getKeyCode()).equals("Right")) {
//right key released
}
}
}
I then used this bit of code in my main constructor
main() {
KeyListener listener = new MyKeyListener();
addKeyListener(listener);
setFocusable(true);
}
This way you wont have your delay when hitting keys.

Java is not picking up keypresses?

I have a program which produces a JFrame and then a JPanel on top of it. For the program, I have tried implementing the KeyListener and then adding the methods (for both components), but the program does not pick any of my key strokes up. What am I doing wrong?
EDIT
This is my code. It is a part of the class which creates the JFrame. It still does not pick up the press of the ESC key.
#Override
public void keyTyped(KeyEvent e) {
}
#Override
public void keyPressed(KeyEvent e) {
int keyCode = e.getKeyCode();
if(keyCode == KeyEvent.VK_ESCAPE){
System.out.println("Hi");
}else{
System.out.println("Hello");
}
}
#Override
public void keyReleased(KeyEvent e) {
}

Without your code, all I can tell you is that usually when people ask this they don't know that the interface KeyListener contain three methods as Agusti-N states in their answer here:
void keyTyped(KeyEvent)
void keyPressed(KeyEvent)
void keyReleased(KeyEvent)
If you use keyTyped and you are using event.getKeyCode() to check for the character entered, this will not work. You should use getKeyChar() for keyTyped and getKeyCode() for keyPressed and keyReleased. Otherwise you'll get null.
You should only use this if you do not have any other alternative, in most cases you want to use Key Bindings.