How would I stop a ball from moving off the screen?

Question

so basically when i use my arrow keys this red ball will move, but I can move it off the screen. How could I make it so that the ball wouldn't be able to move pass the border?

I was thinking about doing something like detecting if the position of the ball was >= the edge of the screen then it would respawn at like the middle, but wasn't sure how I should implement it.

//Name: anon   Date:
   import javax.swing.*;
   import java.awt.*;
   import java.awt.event.*;
   import java.awt.image.*;
  
      private class Key extends KeyAdapter
      { 
         public void keyPressed(KeyEvent e)
         {
            if(e.getKeyCode() == KeyEvent.VK_UP) //arrow key 
               pd.setY( pd.getY()-10);
            if(e.getKeyCode() == KeyEvent.VK_DOWN)
               pd.setY( pd.getY()+10);
            if(e.getKeyCode() == KeyEvent.VK_LEFT)
               pd.setX( pd.getX()-10);
            if(e.getKeyCode() == KeyEvent.VK_RIGHT)
               pd.setX( pd.getX()+10);
               
            
            
               
          }
          
       }
   

Answer 1

How about checking if the x coordinate plus the radius of the circle is out of bounds and then do the same for the y coordinate?

Point circleCenter;
int radius;

int screenW;
int screenH;

if (circleCenter.x + radius > screenW)
    circleCenter.x = screenW - radius;

if (circleCenter.x - radius < 0)
    circleCenter.x = 0 + radius;

if (circleCenter.y + radius > screenH)
    circleCenter.y = screenH - radius;

if (circleCenter.y - radius < 0)
    circleCenter.y = 0 + radius;