So I have the following simple class that's designed to take a valid RSS feed and print it to file. When a valid RSS feed is given (whether a file is selected or not) everything works fine. But when an invalid RSS feed's fed through the XML object is supposed to return null. When that happens, I get a NullPointerException (which is fine if not for the fact that I've enclosed everything in if-else stuff). This is driving me crazy. I mean, NullPointerException in these things is common but usually I know what's throwing it and I can fix it but here I can't tell at all. (Error reporting system of PDE is pretty much crap, in my opinion). Anyway, here's the code:

Hey,

Hey,

2. // Basic Breakout game
   // Code from Matthre Yee-King
   int ponto = 0;
   // brick position
   float brickX;
   float brickY;
3. // brick width and height
   float brickH;
   float brickW;
4. // ball position
   float ballX;
   float ballY;
5. // ball diameter
   float ballD;
6. // ball direction
   float ballDx;
   float ballDy;
7. // bat position
   float batX;
8. //bat width
   float batW;
   float batH;
9. //bat colour
   float batB;
10. void setup() {
      size (500, 500, P2D);
     
      // set sizes of game items
      brickW = 100;
      brickH = 50;
      batW = 100;
      batH = 15;
      ballD = 25;
      batB = 255;
     
      // random brick position
      brickX = random(0, width - brickW);
      brickY = random (0, height / 2);
     
      // bat in the centre
      batX = (width/2) - (batW/2);
     
      // ball atop bat
      ballX = batX + (batW/2);
      ballY = height - batH - (ballD/2);
     
      // ball movement
      ballDx = random(-5, 5);
      ballDy = -5;
      rectMode(CORNER);
      ellipseMode(CENTER);
    }
11. void draw() {
      // check for ball collision
      // with top or sides of bat
      checkBallAgainstBat();
     
      // check for ball collision with
      // left right and top walls
      // and bounce
      checkBallAgainstWalls();
     
      // check ball against brick
      checkBallAgainstBrick();
     
      // move the ball
      ballX += ballDx;
      ballY += ballDy;
      background(0);
     
      // draw the bat
      fill(0, 255, 0);
      rect(batX, height - batH, batW, batH);
     
      // draw the brick
      fill(0, 0, batB);
      batB = (batB + 10) % 255;
      rect(brickX, brickY, brickW, brickH);
     
      // draw the ball
      fill(255, 0, 0);
      ellipse(ballX, ballY, ballD, ballD);
     
      if (keyCode == 37) { // left cursor key
        batX -= 10;
       
        // keep it on the screen
        if (batX < 0) {
          batX = 0;
        }
      }
     
      if (keyCode == 39) {
        batX += 10;
        if (batX > (width - batW)) {
          batX = width - batW;
        }
      }
    }
12. // when they let go of the key, reset the keyCode
    void keyReleased() {
      keyCode = -1;
    }
13. // this function checks if the ball has hit the top or sides of the bat and
    // updates its direction as appropriate so the ball bouncs off the bat
    // I have provided for a function here so that whenever the ball hits
    // the bat, it goes in the opposite direction. For more realism, I added
    // ballD/2, so the ball gets closer before it bounces off.
    // This function is still buggy as I have not been able to work those bugs
    // out.
    void checkBallAgainstBat() {
     if (ballX + ballD/2 > batX && ballX + ballD/2 < batX + batW) {
        if (ballY + ballD/2 - ballD > height-batH-ballD) {
          ballDy *= -1;
          }
      }
    }
14. // this function checks if the ball has hit the brick. It should bounce off
    // the brick and return true if so
    // This function is supposed to work as the checkBallAgainstBat() works
    // but for some reason it is all messed up and I can't seem to figure it
    // out.
    boolean checkBallAgainstBrick() {
      if (ballX + ballD/2 > brickX && ballX + ballD/2 < brickX + brickW) {
        if (ballY > brickH-ballD) {
        ballDy *= -1;
        return true;
      }
      }
          return false;
      }
15. // this function checks if the ball has hit the top, left or right
    // walls and update its
    // direction as appropriate so the ball bounces off the walls
    void checkBallAgainstWalls() {
      if (ballX + ballD > width) {
        ballDx *= -1;
      }
      if (ballX - ballD < 0) {
        ballDx *= -1;
      }
      if (ballY - ballD < 0) {
        ballDy *= -1;
      }
    }

1. // this function checks if the ball has hit the brick. It should bounce off
   // the brick and return true if so
   // This function is supposed to work as the checkBallAgainstBat() works
   // but for some reason it is all messed up and I can't seem to figure it
   // out.
   boolean checkBallAgainstBrick() {
   if (ballX + ballD/2 > brickX && ballX + ballD/2 < brickX + brickW) {
   if (ballY > brickH-ballD) {
   ballDy *= -1;
   return true;
   }
   }
   return false;
   }