Dabbling into processing (coming from ActionScript 3) one of the first things I was looking for was an equivalent of Array.push() and its relatives to store and manage a growing amount of objects during runtime. Astonished I realized that there is no such thing.

After some searching the java Vector-class presented itsalf as a possible surrogat for an AS-like array. Processing being a kind of a “wrapper” for java you can use java classes inside it, like this:

import java.util.Vector;
Vector a = new Vector();
void setup () {}

void draw (){
   a.add(new Dot( random(200), random(200)));
}

class Dot {
  float x,y;
  public Dot ( float x_param, float y_param ){
    x = x_param;
    y = y_param;
  }
}

The vector is not exactly the same as an array in AS (or Perl), but it’s close – see this for details.