How to create effective “select all” checkbox in JSF

Question

I want to implement select all checkbox into JSF h:datatable. This is the code if the h:datatable:

Answer 1

I have used this code to selectAll checkbox :

$(window).load(function () {

    $(document).delegate(".checkall", "click", function(event) {
          $(this).closest("table").find(':checkbox').attr('checked', this.checked);
    });
});

it is working fine when I select/deselect checkbox in header then all the checkbox under that column are selected/deselected. But if again Iam selecting the same, then other checkboxes are not selected. .