import java.util.ArrayList;

class MySafeList extends ArrayList<Double>{

    static ArrayList<Double> mySafeList;

    public boolean add(Double d){
        mySafeList.add(d);
        return true;
    }

    public int size(){
        return mySafeList.size();
    }

    public Double get(int i){
        return mySafeList.get(i);

    }

    static boolean stressTest(int n, int m){
        Thread threads[] = new Thread[n]; //El nombre de tu variable se llama "threads"
        try{
            for(int i=0; i<n; i++){
                threads[i] = new Thread(new ThreadTest(1));
                threads[i].start();
                for(int j=0; j<m;j++){
                    Double d = new Double((double) j);
                    mySafeList.add(d);
                }
            }
            return true;
        }catch(Exception e){
            return false;
        }
    }

    public static void main(String[] args) {
        MySafeList safeList = new MySafeList();
        stressTest(2,4);
    }

}