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我想用Servlet，JSP和Hibernate創建登錄系統。但是我收到一個錯誤，userId ='null'。使用的Java類如下。請問你能幫幫我嗎？Hibernate查詢返回userId ='null'
查詢結果：
休眠：選擇users0_.id如id0_，users0_.email如email0_， users0_.firstName如firstName0_，users0_.lastName如lastName0_， users0_.middleName如middleName0_，users0_。密碼password0_， users0_.userId作爲userId0_從用戶那裏users0_ users0_.userId = '空'
此查詢結果返回重複。
登錄的Servlet：
@WebServlet(name = "Login", urlPatterns = {"/Login"})
public class Login extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String userId = request.getParameter("userId");
String password = request.getParameter("password");
LoginService loginService = new LoginService();
boolean result = loginService.authenticate(userId, password);
Users user = loginService.getUserByUserId(userId);
if(result == true){
request.getSession().setAttribute("user", user);
response.sendRedirect("deneme.jsp");
}
else{
response.sendRedirect("login.jsp");
}
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
@Override
public String getServletInfo() {
return "Short description";
}
}
用戶模型：
Entity
@Table(name="users")
public class Users implements Serializable {
@Id @GeneratedValue
private Long id;
private String firstName;
private String middleName;
private String lastName;
private String email;
private String userId;
private String password;
//Constructor and Getter Setter methods
}
登錄服務：
public class LoginService {
public boolean authenticate(String userId, String password) {
Users user = getUserByUserId(userId);
if(user!=null && user.getUserId().equals(userId) && user.getPassword().equals(password)){
return true;
}else{
return false;
}
}
public Users getUserByUserId(String userId) {
Session session = HibernateUtil.openSession();
Transaction tx = null;
Users user = null;
try {
tx = session.getTransaction();
tx.begin();
Query query = session.createQuery("from Users where userId='"+userId+"'");
user = (Users)query.uniqueResult();
tx.commit();
} catch (Exception e) {
if (tx != null) {
tx.rollback();
}
e.printStackTrace();
} finally {
session.close();
}
return user;
}
public List<Users> getListOfUsers(){
List<Users> list = new ArrayList<Users>();
Session session = HibernateUtil.openSession();
Transaction tx = null;
try {
tx = session.getTransaction();
tx.begin();
list = session.createQuery("from Users").list();
tx.commit();
} catch (Exception e) {
if (tx != null) {
tx.rollback();
}
e.printStackTrace();
} finally {
session.close();
}
return list;
}
}
休眠的Util：
public class HibernateUtil {
private static final SessionFactory sessionFactory;
static {
try {
sessionFactory = new AnnotationConfiguration().configure("hibernate.cfg.xml").buildSessionFactory();
} catch (Throwable ex) {
System.err.println("Initial SessionFactory creation failed." + ex);
throw new ExceptionInInitializerError(ex);
}
}
public static Session openSession() {
return sessionFactory.openSession();
}
}
的hibernate.cfg.xml：
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost/test?zeroDateTimeBehavior=convertToNull</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password"></property>
<property name="show_sql">true</property>
<property name="hbm2ddl.auto">update</property>
<mapping class="com.bookstore.model.Users" />
</session-factory>
</hibernate-configuration>
的login.jsp
<!-- Account Login-->
<div align="right">
<form role="form" action="login" method="post" >
<label class="control-label">User Id:</label>
<input type="text" name="userId" class="span3">
<label class="control-label" >Password:</label>
<input type="password" name="password">
<input type="submit" value="Login" >
</form>
</div>
pleas share login.jsp – shankarsh15
在你的servlet中檢查你是否獲得了userId的值。你正在做String userId = request.getParameter（「userId」）; 。只要做一個Sytem.out.println（userId）;並檢查值。 –
據我所知，URL區分大小寫。但在你的情況下，當你的servlet被映射到'Login'時，你的表單的'action'屬性是'login'。通話功能完全在嗎？ – ujulu