springmvc处理json

<script type="text/javascript">
    $(function(){
        $("#testJson").click(function(){
            var url = this.href;
            var args = {};
            $.post(url, args, function(data){
                for(var i = 0; i < data.length; i++){
                    var id = data[i].id;
                    var lastName = data[i].lastName;
                    
                    alert(id + ": " + lastName);
                }
            });
            return false;
        });
    })
</script>