Struts2下 jsp向action传值出现数据丢失

[CT190]

User.hbm.xml文件：
<hibernate-mapping package="com.ldp.bean">
<class name="User" table="user">
<id name="id" column="id" type="java.lang.String">
<generator class="assigned" />
</id>
<property name="password" column="password" type="java.lang.String"></property>
</class>

UserAction.java文件：

private User user;
private UserService userService;

public void setUser(User user) {
this.user = user;
}

public void setUserService(UserService userService) {
this.userService = userService;
}
public String login() {
user =userService.login(user);
if(user!=null) {
System.out.print("success");
return "success";
}
else return "error";
}

UserDao.java文件：
@Repository
public class UserDao extends HibernateDaoSupport {
//用户登录
@SuppressWarnings("all")
public User login(User user) {
List<User> list = (List<User>) this.getHibernateTemplate().find
("from User where id='"+user.getId() +"' and password='" + user.getPassword() + "'");
if(list.size()!=0 && list!=null){
User u = list.get(0);
return u;
}
return null;
}
}

User.java文件：
public class User {

private String id;
private String password;

public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}

}

jsp文件：
<form action="userlogin" method="post">
<input name="user.id">
<input name="user.password">
<input type="submit" value="登录">
</form>

运行结果：

Hibernate:
select
user0_.id as id1_0_,
user0_.password as password2_0_
from
user user0_
where
user0_.id='null'
and user0_.password='1'


id不见了，password还在.....很郁闷

[CT190]

用request可以获取，问题到底出在哪里？