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Groups > comp.lang.java.programmer > #9450

iteration blues

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So, I wrote this code for some particle effects:

package com.coolfone.particles;

import java.util.Iterator;
import java.util.Vector;

import javax.microedition.khronos.opengles.GL10;

public class FireManager {
	static Vector<Particle> particles = new Vector<Particle>();

	public static void startfire(float x, float y) {
		for (int ctr = 0; ctr < 100; ctr++) {
			Particle p = new Particle();
			p.x = (float) (x + Math.random()-.5);
			p.y = (float) (y + Math.random()-.5);
			p.dx = (float) (Math.random()-.5)/4f;
			p.dy = (float) (Math.random()-.5)/4f;
			p.timeleft = (int) (Math.random() * 50 + 50);
			particles.add(p);
		}
	}

	public static void burnfire() {
		Iterator<Particle> i = particles.iterator();
		Vector<Particle> removelist = new Vector<Particle>();
		while (i.hasNext()) {
			Particle p = i.next();
			p.move();
			p.timeleft--;
			if (p.timeleft == 0) removelist.add(p);

		}
		particles.removeAll(removelist);

	}

	public static void drawfire(GL10 gl) {
		Iterator<Particle> i = particles.iterator();
		while (i.hasNext()) {
			Particle p = i.next();
			p.draw(gl);
		}
	}

}

I'm concerned about inefficiency in the burnfire function.  Does
anyone know how to rewrite this quickly if particles was a linked
list?  The main issue is that I'm not sure if removing items during
iteration messes up the iterator.

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iteration blues bob <bob@coolgroups.com> - 2011-11-03 08:37 -0700
  Re: iteration blues Knute Johnson <nospam@knutejohnson.com> - 2011-11-03 08:51 -0700
    Re: iteration blues Lew <lewbloch@gmail.com> - 2011-11-03 09:32 -0700
      Re: iteration blues Arne Vajhøj <arne@vajhoej.dk> - 2011-11-04 21:00 -0400
        Re: iteration blues spk <jhic@speak.invalid> - 2011-11-05 07:48 -0400
  Re: iteration blues Henk van Voorthuijsen <voorth@xs4all.nl> - 2011-11-03 09:31 -0700
    Re: iteration blues Lew <lewbloch@gmail.com> - 2011-11-03 13:50 -0700
      Re: iteration blues Henk van Voorthuijsen <voorth@xs4all.nl> - 2011-11-04 08:07 -0700
    Re: iteration blues Arne Vajhøj <arne@vajhoej.dk> - 2011-11-04 21:02 -0400
  Re: iteration blues Roedy Green <see_website@mindprod.com.invalid> - 2011-11-03 10:08 -0700
  Re: iteration blues Travers Naran <tnaran@gmail.com> - 2011-11-03 22:22 -0700
  Re: iteration blues Robert Klemme <shortcutter@googlemail.com> - 2011-11-04 10:34 +0100
    Re: iteration blues Lew <lewbloch@gmail.com> - 2011-11-04 10:46 -0700
      Re: iteration blues Robert Klemme <shortcutter@googlemail.com> - 2011-11-04 23:55 +0100
        Re: iteration blues Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-11-04 21:06 -0400
        Re: iteration blues Lew <lewbloch@gmail.com> - 2011-11-04 20:30 -0700
        Re: iteration blues bob <bob@coolgroups.com> - 2011-11-05 12:40 -0700
          Re: iteration blues Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-11-05 16:14 -0400
            Re: iteration blues Lew <lewbloch@gmail.com> - 2011-11-05 13:41 -0700
    Re: iteration blues bob <bob@coolgroups.com> - 2011-11-04 13:42 -0700

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