1.首先ajax的访问方法如下：

$.getJSON("requestUrl?callback=?",function(data){
	
});

public String getBirthdayUser() {
		List<User> list = userService.listAll(1,100);
		Calendar cal = Calendar.getInstance();
		int month = cal.get(Calendar.MONTH) + 1;
		int day = cal.get(Calendar.DAY_OF_MONTH);
		List<User> brithdayUser = new ArrayList<User>();
		List<String> birthdayUserName = new ArrayList<String>();
		for (User user : list) {
			if (user.getIdCard() != null && user.getIdCard().length() == 18) {
				if (Integer.valueOf(user.getIdCard().substring(10,12)) == month
						&& Integer.valueOf(user.getIdCard().substring(12,14)) == day) {
					brithdayUser.add(user);
					birthdayUserName.add(user.getUserName());
				}
			}
		}
		HttpServletResponse response = ServletActionContext.getResponse();
		response.setCharacterEncoding("utf-8");
		userJson.put("birthdayUser",birthdayUserName);
		return "getBirthdayUserSuccess";

	}

<result name="getBirthdayUserSuccess" type="json">
				<param name="root">userJson</param>
				<param name="callbackParameter">callback</param>
			</result>

至此 ajax结合struts 实现跨域访问结束