code: @Override
  	public Object doOutParameter(final String key, final Object val) {
  		if (getFilters().isEmpty()) {
  			return val;
  		}
  		Object obj = val;
  		for (final SqlFilter filter : getFilters()) {
  			obj = filter.doOutParameter(key, obj);
  		}
  		return obj;
  	}
docs: {@inheritDoc}
  
  @see jp.co.future.uroborosql.filter.SqlFilter#doOutParameter(java.lang.String, java.lang.Object)