Ajax访问Servlet的跨域请求问题—Access-Control-Allow-Origin

<script type="text/javascript" src="js/jquery-3.1.1.min.js"></script>
<form >
用户名：<input type="text" id="userName"/><br/>
密码：<input type="password" id="userPwd"/><br/>
<input type="button" value="登录" id="sender">
</form>
<div id="messageDiv"></div>

<script>
$('#sender').click(function(){
var userName=document.getElementById('userName').value;
var userPwd=document.getElementById('userPwd').value;
var user={userName:userName,userPwd:userPwd};

var url="http://10.30.1.102:8080/partner-back/LoginUserServlet";
$.post(url, JSON.stringify(user), function(data) {
$("#messageDiv").html(data);
});
});
</script>

public class LoginUserServlet extends HttpServlet {
private static final long serialVersionUID = 1L;

public LoginUserServlet() {
super();
}

protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}

protected void doOptions(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doPost(request, response);
}

protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

Writer out = response.getWriter();
JSONObject jsonObject=new JSONObject();

//获取客户端发送的json数据
JSONObject json=null;
try {
json=JsonReader.receivePost(request);
} catch (Exception e) {
e.printStackTrace();
jsonObject.put("message", "用户登录失败！");
out.write("{}");
out.flush();
return;
}
System.out.println(json);

UserService userService=new UserService();
//将建json对象转换为java对象
User loginUser = (User)JSONObject.toBean(json,User.class);
User user = userService.LoginUser(loginUser);

if(user!=null){
//将java对象转换为json对象
jsonObject.put("user", JSONObject.fromObject(user));
jsonObject.put("message", "用户登录成功！");
jsonObject.put("token", token);
}else{
jsonObject.put("message", "用户登录失败！");
}
out.write(jsonObject.toString());
out.flush();
}
}

@WebFilter("/*")
public class CORSFilter implements Filter {

public CORSFilter() {
}

public void destroy() {
}

public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
//设置跨域请求
HttpServletResponse response = (HttpServletResponse) res;
response.setHeader("Access-Control-Allow-Origin", "*");
response.setHeader("Access-Control-Allow-Methods", "POST, GET, DELETE, PUT");
response.setHeader("Access-Control-Max-Age", "3628800"); 

System.out.println("设置跨域请求");
chain.doFilter(req, response); 
}

public void init(FilterConfig fConfig) throws ServletException {
}
}