    public void pageBeginRender(PageEvent event) {
        if (getUser() == null) {        
            setUser(new User());
        }
        if (getUsers() == null) {
            setUsers(new ArrayList());
        }        
        if (isFirstRender()) {
            setFirstRender(false);
        } else {
            search(event.getRequestCycle());
        }
    }

    public void pageBeginRender(PageEvent event) {
        if (getUser() == null) {        
            setUser(new User());
        }
        if (getUsers() == null) {
            setUsers(new ArrayList());
        }        
        if (isFirstRender()) {
            getUsers().clear();     
            setFirstRender(false);
        } else {
            search(event.getRequestCycle());
        }
    }
