Re : Exporting to dxf or pdf

import processing. pdf.*;
ArrayList history = new ArrayList();
float distthresh = 60;

void setup(){
  size(900,600);
  background(255);
  stroke(0,50);
  smooth();
}


void draw(){
  
}

void mouseDragged(){

  PVector d = new PVector(mouseX,mouseY,0);
  history.add(0,d);
  
  for (int p=0; p<history.size(); p++){
    PVector v = (PVector) history.get(p);
    float joinchance = p/history.size() + d.dist(v)/distthresh;
    if (joinchance < random(0.4))  line(d.x,d.y,v.x,v.y);
  }
}

void keyPressed(){
  if (key == ' ') {
    background(255);
    history.clear();
  }
}

Then I get errors when I type in the rest of the code below when I run the file. It does not export.

void setup() {
  size(400, 400, PDF, "filename.pdf");
}

void draw() {
  // Draw something good here
  line(0, 0, width/2, height);

  // Exit the program 
  println("Finished.");
  exit();
}