index ot of bounds exception

game.getS().getVehicles().get(1).updatePosition(positions.get(0));

we are making a client - server racing game and we got this exception in this exact line what can we do or what can we change? here i will show you the all code:

package speedrace.client;

import static speedrace.common.Config.*;

import speedrace.common.*;
import speedrace.game.Car;
import speedrace.game.CarGame;
import speedrace.game.Player;

import java.awt.geom.Point2D;
import java.awt.geom.Point2D.Float;
import java.rmi.*;
import java.rmi.server.*;
import java.util.ArrayList;
import java.util.Vector;

import javax.swing.*;

public class SpeedRaceClientController extends UnicastRemoteObject implements
        RaceObserver, RaceUpdate
{
    private RaceSubject serverGet;
    private RaceUpdate serverSet;
    private SpeedRaceClientView view;

    private int clientID = 0;
    private Player currentPlayer = null;
    private CarGame game = new CarGame();

    public SpeedRaceClientController() throws Exception
    {
        super();
        game.setVisible(false);
    }

    @Override
    public Player getCurrentPlayer() throws RemoteException
    {
        return currentPlayer;
    }

    @Override
    public void setCurrentPlayer(Player currentPlayer) throws RemoteException
    {
        this.currentPlayer = currentPlayer;

    }

    @Override
    public int getClientID()
    {
        return clientID;
    }

    @Override
    public void setClientID(int clientID)
    {
        this.clientID = clientID;
    }

    @Override
    public CarGame getGame()
    {
        return game;
    }

    @Override
    public void setGame(CarGame game)
    {
        this.game = game;
    }

    public void begin(SpeedRaceClientView view)
    {
        this.view = view;

        try
        {
            String ip = view.inputIP();
            String URL = "rmi://" + ip + "/" + SERVICE;

            serverSet = (RaceUpdate) Naming.lookup(URL);
            serverGet = (RaceSubject) Naming.lookup(URL);

            serverGet.attach(this);
        }
        catch (Exception ex)
        {
            ex.printStackTrace();
            view.error("Trouble connecting to server");
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            System.exit(1);
        }
    }

    @Override
    public void updatePlayerList(Vector<Player> playersList)
            throws RemoteException
    {
        view.showOnlinePlayers(playersList);

    }

    @Override
    public void registerNewPlayer(Player player, int clientID)
            throws RemoteException
    {
        try
        {
            serverSet.registerNewPlayer(player, clientID);
        }
        catch (RemoteException ex)
        {
            ex.printStackTrace();
            view
                    .error("Trouble connecting to server. Please restart the server.");
            System.exit(1);
        }

    }

    @Override
    public void startGame() throws RemoteException
    {

        try
        {
            serverSet.startGame();

        }

        catch (RemoteException re)
        {
            re.printStackTrace();
            view
                    .error("Trouble connecting to server. Please restart the server.");
            System.exit(1);
        }
    }

    @Override
    public void startTheGame(ArrayList<Point2D.Float> positions,
            Vector<RaceObserver> observers) throws RemoteException
    {

        switch (clientID)
        {
            case 1:
                game.updatePosition(273, 471);
                break;
            case 2:
                game.updatePosition(315, 408);
                break;
            case 3:
                game.updatePosition(353, 471);
                break;
            case 4:
                game.updatePosition(395, 408);
                break;
            case 5:
                game.updatePosition(433, 471);
                break;
            case 6:
                game.updatePosition(475, 408);
                break;
            case 7:
                game.updatePosition(513, 471);
                break;
            case 8:
                game.updatePosition(555, 408);
                break;
        }

        for (int i = 1; i < observers.size(); i++)
        {
            game.getS().getVehicles().add(
                    new Car(getClass().getResource(
                            "/speedrace/game/bluecar.png")));

            game.getS().getVehicles().get(i).setMass(0.9f);
            game.getS().getVehicles().get(i).setMaxSteering(500.0f);
            game.getS().getVehicles().get(i).updateVelocity(80.0f, 0.0f);
        }
        updatePosition(clientID, positions);

        game.setVisible(true);
        game.getS().requestFocusInWindow();
        sendCurrentCarPosition(game.getS().getVehicles().get(0).getPosition(),clientID);
    }

    public void updatePosition(int id, ArrayList<Point2D.Float> positions){
        if(id==1){
            for (int i = 1; i < game.getS().getVehicles().size(); i++)
            {
                game.getS().getVehicles().get(i).updatePosition(positions.get(i));              
            }

        }else if(id==2){
            game.getS().getVehicles().get(1).updatePosition(positions.get(0));              
            for (int i = 2; i < game.getS().getVehicles().size(); i++)
            {
                game.getS().getVehicles().get(i).updatePosition(positions.get(i));  
            }
        }else if(id==3){
            game.getS().getVehicles().get(1).updatePosition(positions.get(0));  
            game.getS().getVehicles().get(2).updatePosition(positions.get(1));
            for (int i = 3; i < game.getS().getVehicles().size(); i++)
            {
                game.getS().getVehicles().get(i).updatePosition(positions.get(i));  
            }
        }else if(id==4){
            game.getS().getVehicles().get(1).updatePosition(positions.get(0));  
            game.getS().getVehicles().get(2).updatePosition(positions.get(1));
            game.getS().getVehicles().get(3).updatePosition(positions.get(2));
            for (int i = 4; i < game.getS().getVehicles().size(); i++)
            {
                game.getS().getVehicles().get(i).updatePosition(positions.get(i));  
            }
        }else if(id==5){
            game.getS().getVehicles().get(1).updatePosition(positions.get(0));  
            game.getS().getVehicles().get(2).updatePosition(positions.get(1));
            game.getS().getVehicles().get(3).updatePosition(positions.get(2));
            game.getS().getVehicles().get(4).updatePosition(positions.get(3));
            for (int i = 5; i < game.getS().getVehicles().size(); i++)
            {
                game.getS().getVehicles().get(i).updatePosition(positions.get(i));  
            }
        }else if(id==6){
            game.getS().getVehicles().get(1).updatePosition(positions.get(0));  
            game.getS().getVehicles().get(2).updatePosition(positions.get(1));
            game.getS().getVehicles().get(3).updatePosition(positions.get(2));
            game.getS().getVehicles().get(4).updatePosition(positions.get(3));
            game.getS().getVehicles().get(5).updatePosition(positions.get(4));
            for (int i = 6; i < game.getS().getVehicles().size(); i++)
            {
                game.getS().getVehicles().get(i).updatePosition(positions.get(i));  
            }
        }else if(id==7){
            game.getS().getVehicles().get(1).updatePosition(positions.get(0));  
            game.getS().getVehicles().get(2).updatePosition(positions.get(1));
            game.getS().getVehicles().get(3).updatePosition(positions.get(2));
            game.getS().getVehicles().get(4).updatePosition(positions.get(3));
            game.getS().getVehicles().get(5).updatePosition(positions.get(4));
            game.getS().getVehicles().get(6).updatePosition(positions.get(5));
            for (int i = 7; i < game.getS().getVehicles().size(); i++)
            {
                game.getS().getVehicles().get(i).updatePosition(positions.get(i));  
            }
        }else if(id==8){
            game.getS().getVehicles().get(1).updatePosition(positions.get(0));  
            game.getS().getVehicles().get(2).updatePosition(positions.get(1));
            game.getS().getVehicles().get(3).updatePosition(positions.get(2));
            game.getS().getVehicles().get(4).updatePosition(positions.get(3));
            game.getS().getVehicles().get(5).updatePosition(positions.get(4));
            game.getS().getVehicles().get(6).updatePosition(positions.get(5));
            game.getS().getVehicles().get(7).updatePosition(positions.get(6));
        }
    }

    @Override
    public void updateCarPosition(ArrayList<Point2D.Float> positions)
            throws RemoteException
    {
        for (int i = 0; i < positions.size(); i++)
        {
            System.out.println(i+"= ["+positions.get(i).x+", "+positions.get(i).y+"]");         
        }
        System.out.println("My clienID is: "+clientID+" my car size is: "+ game.getS().getVehicles().size());
        updatePosition(clientID, positions);

    }

    @Override
    public void sendCurrentCarPosition(final Point2D.Float position, final int clientID) throws RemoteException
    {

        class UpdateThread implements Runnable
        {
            boolean running = true;
            public void run()
            {
                while (running)
                {
                    try
                    {
                        System.out.println(clientID+" send  his position to the server: "+position.x+", "+position.y);
                        serverSet.sendCurrentCarPosition(position, clientID);
                        Thread.sleep(20);
                    }

                    catch (RemoteException re)
                    {
                        re.printStackTrace();
                        view
                                .error("Trouble connecting to server. Please restart the server.");
                        System.exit(1);
                    }
                    catch (InterruptedException e)
                    {
                        e.printStackTrace();
                        view
                                .error("Trouble connecting to server. Please restart the server.");
                        System.exit(1);
                    }
                }
            }
        }
        final UpdateThread t = new UpdateThread();
        new Thread(t).start();
    }



}

In your for-loops you almost always start from 1. Is that correct?

To let us find the problem, you should post more code, I guess.

Either positions has 0 elements or game.getS().getVehicles() has <2 elements. Test for those conditions and act appropriately.