add action to table

I have a probleme with handleAction, I can't handle any action.
I want to combine treatment with each action in method void handleAction but without sucess,
even the logger is not displayed.
I use vaadin 6.7.3 in my project.
my goal is to enable the lazy loading between table and databases.

this is my code
getList().addActionHandler(new Action.Handler() {

public Action[] getActions(Object target, Object sender) {
markedRows = new HashSet<Object>();
if (markedRows.contains(target)) {
return ACTIONS_MARKED;

} else {
LOGGER.info("target " + target);
return ACTIONS_UNMARKED;
}

}

public void handleAction(Action action, Object sender, Object target) {
LOGGER.info("target " + action);
if (ACTION_MARK.equals(action)) {
LOGGER.info("markedRows");
markedRows.add(target);
getList().refreshRowCache();
} else if (ACTION_UNMARK.equals(action)) {
// LOGGER.info("hellllo");
markedRows.remove(target);
getList().refreshRowCache();
} else if (ACTION_LOG.equals(action)) {
Item item = getList().getItem(target);
addComponent(new Label("Saved: " + target + ", " + item.getItemProperty("roleId").getValue()));
i = "ACTION_LOG";
}
LOGGER.info("markedRows");

}
});