Java spaceshooter design

Question

Hey all,
i've been making a spaceshooter in java, but now i'm having design problems. my code is apparantly inefficient and lags like crazy on certain comps, but works fine on good comps. i've experimented with threading, but dont know an efficient way to thread. So far i have a thread to update drawing, a thread to updte movement, and a thread to check 4 all collisions. i also have a bunch of random threads that certain objects create, but thats not that big of a deal. also i'm using particle effects to create a shot, but thats the one thats causing the greatest lag as it hsato loop through to draw each tiny piece. Anyway i'm confused right now on how to make an efficient design so i'm asking for ideas and help on how to create a design. plz help all u can and plz dont flame me =(

Answer 1

hmmm aiight. my code is somewhat confusing...wud anyone mind telling me how they wud do it? neway here's my code:
//code from SimpleEnemy.java  
EnemyShotPiece p=new EnemyShotPiece((int)Math.round(x), (int)Math.round(y));
pieces.add(p);  //pieces is a vector of EnemyShotPiece
int length=pieces.size();
for(int i=0; i<length; i++)
     if(pieces.get(i).radius()<=0)
          pieces.remove(i);
          i-=1;
     length=pieces.size();
//out.println((" "+pieces.size()));
for(EnemyShotPiece ep:pieces)
     ep.move();
     ep.draw(g);
public class EnemyShotPiece extends MovingObject
     double radius;
     int step=0;
     public EnemyShotPiece(int row, int col)
          super(row, col);
          //this.direction=direction;
          //this.speed=speed;
          //out.println(direction*(180.0/Math.PI));
          radius=10;
          //player=p;
     public void draw(Graphics g)
          //move();
          //out.println(row.get()+" "+col.get()+" "+radius);
          //g.drawArc(row.get(), col.get(), (int)Math.round(radius), (int)Math.round(radius), 0, 360);
          Graphics2D gg=(Graphics2D)g;
          //Color coll=gg.getColor();
          //gg.setColor(new Color(random.nextInt(256),random.nextInt(256),random.nextInt(256)));     
          Paint p=gg.getPaint();
          final GradientPaint gp=new GradientPaint(3, 3, Color.orange, width()/2.0f, height()/2.0f, Color.red, true);
          gg.setPaint(gp);          
          Ellipse2D e=new Ellipse2D.Double(row.get()+radius/2, col.get(), radius, radius);
          gg.fill(e);
          //gg.setPaint(Color.green);
          //gg.setStroke(new BasicStroke());
          //gg.draw(e);
          //gg.setPaint(gp);
          gg.draw(e);
          //e.setFrame()
          //gg.setColor(Color.ORANGE);
          //gg.drawOval((int)Math.round(row.get()+radius/2), (int)Math.round(col.get()), (int)Math.ceil(radius), (int)Math.ceil(radius));
          //gg.fillOval((int)Math.round(row.get()+radius/2), (int)Math.round(col.get()), (int)Math.ceil(radius), (int)Math.ceil(radius));
          //gg.setColor(coll);
          gg.setPaint(p);
          //g.fillOval(row.get(), col.get(), (int)Math.round(radius), (int)Math.round(radius));
     public void setImage()
     public int radius()
          return (int)Math.round(radius);
     public void move() //object doesnt move itself, only radius gets decremented
          radius-=.5;
}sorry if the code is knda funky, i had a lot of test statements in there.