Okay so I want to make the ship fire photons (lines) and makes a sound when the spacebar or another key is hit.

In Java, understanding there are other components at play here, I think it would look something like:

<code>
   if (e.getKeyChar() == ' ' && ship.active) {
     if (sound & !paused)
       fireSound.play();
     photonTime = System.currentTimeMillis();
     photonIndex++;
     if (photonIndex >= MAX_SHOTS)
       photonIndex = 0;
     photons[photonIndex].active = true;
     photons[photonIndex].x = ship.x;
     photons[photonIndex].y = ship.y;
     photons[photonIndex].deltaX = 2 * MAX_ROCK_SPEED * -Math.sin(ship.angle);
     photons[photonIndex].deltaY = 2 * MAX_ROCK_SPEED *  Math.cos(ship.angle);
   }
</code>

My problem is trying to do this as a subclass in Processing that fits into:

<code>
// ROCKET AND ASTEROIDS
// This code is the basis for an object-oriented version of the old arcade game Asteroids!
//   - originally coded by Michael Mateas and Mayhew Seavey III
//   - revised by Beth A. Dillon

Rocket r1 = new Rocket(50, 60, 0);
Asteroid[] a;
// we can change the number of asteroids here.
final int numAsteroids = 5;


void setup() {
 background(0);
 size(400, 400);
 noFill();
 stroke(255);
 r1.drawMe();


 a = new Asteroid[numAsteroids];
 for(int i = 0; i < numAsteroids; i++) {
   a[i] = new Asteroid();
 }
}

void draw() {
 background(0);
 if (keyPressed) {
   if (key == CODED) {
     if (keyCode == RIGHT) {
       r1.rotateClockwise();
     }
     else if (keyCode == LEFT) {
       r1.rotateCounterclockwise();
     }
   }
   else if (key == ' ') {
     r1.fireThrusters();
   }
 }
 r1.drawMe();
 for(int i = 0; i < numAsteroids; i++) {
   // makes an asteroid disappear if we collide with it
   if(!((abs(a[i].xPos - r1.xPos) < 20) && (abs(a[i].yPos - r1.yPos) < 20))) {
     a[i].drawMe();
   }
 }
}

class Asteroid {
 // fields
 float rotation = 0;
 float xPos, yPos;
 float velocityX, velocityY;
 long lastDrawMillis = 0;


 //constructor
 Asteroid() {
   xPos = random(0, 400);
   yPos = random(0, 400);
   rotation = random(0, TWO_PI);
   velocityX = sin(rotation)*10;
   velocityY = -cos(rotation)*10;
 }


 void drawMe() {
   long currentMillis = millis();
   float timeSinceLastDraw = ((float)currentMillis - (float)lastDrawMillis)/1000;
   lastDrawMillis = currentMillis;
   xPos = xPos + velocityX * timeSinceLastDraw;
   yPos = yPos + velocityY * timeSinceLastDraw;
   if (xPos > 400) {
     xPos -= 400;
   }
   else if (xPos < 0) {
     xPos += 400;
   }
   if (yPos > 400) {
     yPos -= 400;
   }
   else if (yPos < 0) {
     yPos += 400;
   }

   pushMatrix();
   translate(xPos, yPos);
   rotate(rotation);

   int[] xpts = {
     -20, 0, 18, 22, 5, 20, 17, -3, -17, -18, -26                    };
   int[] ypts = {
     -15, -24, -20, -5, 0, 10, 20, 26, 23, 14, 7                    };

   beginShape(POLYGON);
   for(int i = 0; i < 11; i++) {
     vertex(xpts[i], ypts[i]);
   }
   endShape();
   popMatrix();
 }
}


class Rocket {
 // fields
 float rotation = 0;
 float xPos;
 float yPos;
 final int halfWidth = 10;
 final int halfHeight= 10;
 float velocityX = 0;
 float velocityY = 0;
 long lastDrawMillis = 0;

 // constructor
 Rocket(int initialX, int initialY, float initialRot) {
   xPos = initialX;
   yPos = initialY;
   rotation = initialRot;
 }

 void drawMe() {
   long currentMillis = millis();
   float timeSinceLastDraw = ((float)currentMillis - (float)lastDrawMillis)/1000;
   lastDrawMillis = currentMillis;
   xPos = xPos + velocityX * timeSinceLastDraw;
   yPos = yPos + velocityY * timeSinceLastDraw;
   if (xPos > 400) {
     xPos -= 400;
   }
   else if (xPos < 0) {
     xPos += 400;
   }
   if (yPos > 400) {
     yPos -= 400;
   }
   else if (yPos < 0) {
     yPos += 400;
   }

   pushMatrix();
   translate(xPos, yPos);
   rotate(rotation);

   triangle(0, -halfHeight, -halfWidth, halfHeight, halfWidth,halfHeight);

   rectMode(CORNERS);
   rect(-halfWidth + 5, halfHeight, -halfWidth + 8, halfHeight + 3);
   rect(halfWidth - 8, halfHeight, halfWidth - 5, halfHeight + 3);
   popMatrix();
 }

 void rotateClockwise() {
   rotation = rotation + 0.1;
 }

 void rotateCounterclockwise() {
   rotation = rotation - 0.1;
 }

 void fireThrusters() {
   velocityX = velocityX + sin(rotation) * 1;
   velocityY = velocityY - cos(rotation) * 1;
 }
}

</code>