Struts+Ajax实现登录验证

@Override
public Map login(User user) throws Exception {
Map<String, Object> map = new HashMap<String, Object>();
//		Transaction tx = session.beginTransaction();
String hql="from User where userNum=?";
List<User> list=this.getHibernateTemplate().find(hql,new Object[]{user.getUserNum()});
//		Query query = session.createQuery("from User where userNum=?");
//		query.setString(0, user.getUserNum());
//		List<User> list = query.list();
if (list.size() > 0 && list != null) {// 用户名存在
User loginUser = list.get(0);
if (user.getPassword() != null
&& user.getPassword().trim()
.equals(loginUser.getPassword())) {
map.put("user", loginUser);
} else {
// 添加提示信息，用户名或密码不正确
//				System.out.println("用户名或密码不正确");
map.put("msg", "用户名或密码不正确");
}
} else {
// 用户名不存在
//			System.out.println("用户名不存在");
map.put("msg", "用户名不存在");
}
//		tx.commit();
releaseSession(session);
return map;
}

private User user;
private String msg;
public String login()throws Exception{
System.out.println("进入action中login");
System.out.println("userNum="+user.getUserNum());
System.out.println("password="+user.getPassword());
//		if(osDao.login(user)){
//			Map session=ActionContext.getContext().getSession();
//			session.put("userNum", user.getUserNum());
//			result="success";
//		}
if(user!=null){
Map<String, Object> map=osDao.login(user);
user=(User) map.get("user");
if(user!=null){
Map session=ActionContext.getContext().getSession();
session.put("user", user);
session.put("userNum", user.getUserNum());
session.put("password", user.getPassword());
session.put("nikename", user.getNikename());
session.put("role", user.getRole());
session.put("id", user.getId());
session.put("sex", user.getSex());
msg="true";
return "success";
}else{
msg=(String) map.get("msg");
}
}
return "login";
}

<package name="house-json" extends="json-default">
<action name="login" class="UserAction" method="{1}">
<result name="success" type="json">
<param name="root">msg</param>
</result>
<result name="login" type="json">
<param name="root">msg</param>
</result>
</action>
</package>

<form action="" method="post" name="login_form">
<label> 工  号： </label> <input type="text" name="user.userNum" id="userNum"/>
<label> 密  码： </label> <input type="password" name="user.password" id="password"/>
<input type="button" class="login-sub" value="" onclick="doLogin();"/>
<br />
<p id="msg"></p>
</form>

function doLogin(type){
$("#msg").html("");
var name=$("#userNum").val();
var pw=$("#password").val();
var url = 'login.action?user.userNum='+name+'&user.password='+pw;
if(name!=null && name!='' && pw!=null && pw!=''){
$.ajax({
url: url,
type:"post",
dataType: "json",
async: false,
success:function(data){
if(data.user!=null){
alert("登录成功!");
location.href="<%=basePath%>index.jsp";
}else{
$("#msg").text();
$("#msg").append(data.msg);
}
}
});
}else{
$("#msg").append("请输入用户名或密码");
}
}