用widow.location.href发出的请求，action里的list不能在页面遍历

js部分
function selectcountry(){
var countryid = document.getElementById("cid").value;
window.location.href="countryDetil?countryID="+countryid;
}

            <ul>
                        <s:iterator value="countrySchool">
                            <li><a href="#"><img src="${qmOLLXSPIC }">
                                    <h3>${qmOLLXSchineseName}</h3></a></li>
                        </s:iterator>
                        <div class="clear"></div>
                    </ul>

action里的方法
private List countrySchool;
public String countryDetils(){
this.onload();
HttpServletRequest request = ServletActionContext.getRequest();
String a = request.getParameter("countryID");
country = (QMOLCountry) service.getOneByID(QMOLCountry.class, Integer.parseInt(a));
PageObject page = service.getListByPageBySize(QMOLLXSchool.class, " qmOLCountry.id="+Integer.parseInt(a), 5, 1);
countrySchool = QMGeneralTools.changList(page.getList(), QMOLLXSchool.class);
return QMConstants.ACTION_SUCCESS;
}

private List<QMOLLXSchool> getCountrySchool() {
    return countrySchool;
}
private void setCountrySchool(List<QMOLLXSchool> countrySchool) {
    this.countrySchool = countrySchool;
}