EL表达式

                    <input type="text" style="display:none" name="id" value="${users.id}">
                    <ul>
                        <li><span>会员昵称：</span> <input type="text" name="name"
                            value="${users.name}" id="name"></li>
                        <li><span>电话号码：</span> <input type="text" name="mobile"
                            value="${users.mobile}" id="mobile"></li>
                        <li><span>电子邮箱：</span> <input type="text" name="email"
                            value="${users.email}" id="email"></li>
                        <li><span>身份证：</span> <input type="text" name="idcard"
                            value="${users.idcard}" id="idcard"></li>
                        <li><span>联系地址：</span> <input type="text" name="address"
                            value="${users.address}" id="address"></li>
                        <li>
                            <button type="submit" name="submit" class="btn">更新</button>
                        </li>
                    </ul>

public class GetUserAction extends BaseAction {
    private IUsersDAO usersDAO = new UsersDAOImpl();
    private int userid;

    @Override
    public String execute() throws Exception {
        Users users = usersDAO.get(userid);
        requestMap.put("users", users);
        return SUCCESS;
    }

    public int getUserid() {
        return userid;
    }

    public void setUserid(int userid) {
        this.userid = userid;
    }
}