public static void removeItemFromMap(Map<String, Integer> map) {
    Iterator<Map.Entry<String, Integer>> iterator = map.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, Integer> pair = iterator.next();
        int zp = pair.getValue();
        if(zp<500)
            iterator.remove();
    }

}
public static void removeItemFromMap(Map<String, Integer> map) {
    Iterator<Map.Entry<String, Integer>> iterator = map.entrySet().iterator();
    while (iterator.hasNext()) {
        Map.Entry<String, Integer> pair = iterator.next();
        int zp = pair.getValue();
        if(zp<500)
            map.remove(pair.getKey());
    }

}