String className = getSelectedClasse();
Integer minLevel = (Integer) spinnerMin.getValue();
Integer maxLevel = (Integer) spinnerMax.getValue();
CompositeListFilter<Spell> filter = new CompositeListFilter<Spell>();
filter.addFilter(new MinLevelListFilter(className, minLevel));
filter.addFilter(new MaxLevelListFilter(className, maxLevel));
return filter;
}