Stuff in the main method -

List l = new ArrayList();
        for (int i = 0; i < 10; i++) {
            mobify.model.Stock s = new mobify.model.Stock();
            s.setIdStock(i);
            l.add(i);
            if(i==5){
                l.add(i);
            }
            if(i==8){
                l.remove(i);
            }
        }
        List<Object> objectCount = ToolsStack.objectCount(l);
        for (int i = 0; i < objectCount.size(); i++) {
            mobify.model.Stock object = (mobify.model.Stock) objectCount.get(i);
            System.out.println(object.getIdStock());
        }




public static List<Object> objectCount(List a){
        HashMap<Integer, Object> hashXcounter = new HashMap<Integer, Object>();
        Map<Integer,Object> hashXObject = new HashMap<Integer, Object>();

        Map<Object, Integer> ordered = new HashMap<Object, Integer>();
        for (int i = 0; i < a.size(); i++) {
            Object object = a.get(i);
            if(hashXcounter.get(object.hashCode())!=null){
                hashXcounter.put(object.hashCode(), hashXcounter.get(object.hashCode()));
            }else{
                hashXcounter.put(object.hashCode(), 0);
                hashXObject.put(object.hashCode(), object);
            }
        }
        Collection l =  hashXcounter.values();
        for(Map.Entry e: hashXcounter.entrySet()){
            Integer key = (Integer) e.getKey();
            Integer max = (Integer) Collections.max(l);
            ordered.put(hashXObject.get(key), max);
            l.remove(max);
        }

        return ((List)ordered.values());
    }