【发布时间】：2020-07-27 14:41:22
【问题描述】：
Hibernate 和数据库连接问题（数据未显示在 JSP 页面上） 我想在“ShowDetails.jsp”上显示我的表格数据。但它没有显示，我也尝试通过 Hibernate 映射但我面临同样的问题..
我是 Hibernate 的新手。
http://localhost:8081/jsp-hibernate-curd/ShowDetails.jsp
例外：
java.lang.NoSuchFieldError: TRACE
at org.jboss.logging.Log4jLogger.translate(Log4jLogger.java:64)
at org.jboss.logging.Log4jLogger.isEnabled(Log4jLogger.java:39)
at org.jboss.logging.Logger.isTraceEnabled(Logger.java:98)
at org.hibernate.cfg.Configuration.<init>(Configuration.java:118)
at org.hibernate.cfg.AnnotationConfiguration.<init>(AnnotationConfiguration.java:87)
at org.com.dao.UserDao.<clinit>(UserDao.java:19)
at org.com.servlet.UserServlet.<init>(UserServlet.java:18)
模型类(UserBean.java)
package org.com.bean;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name="userdata")
public class UserBean {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name="id")
private int id;
@Column(name="name")
private String userName;
@Column(name="password")
private String userPass;
@Column(name="email")
private String userEmail;
@Column(name="country")
private String userCountry;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getUserPass() {
return userPass;
}
public void setUserPass(String userPass) {
this.userPass = userPass;
}
public String getUserEmail() {
return userEmail;
}
public void setUserEmail(String userEmail) {
this.userEmail = userEmail;
}
public String getUserCountry() {
return userCountry;
}
public void setUserCountry(String userCountry) {
this.userCountry = userCountry;
}
}
UserDao.class
package org.com.dao;
import java.util.List;
import org.com.bean.UserBean;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.AnnotationConfiguration;
public class UserDao {
private static SessionFactory sessionFactory;
static {
try {
sessionFactory= new AnnotationConfiguration().configure().buildSessionFactory();
}
catch(Throwable e)
{
System.out.println("Exception" + e);
throw new ExceptionInInitializerError(e);
}
}
public static SessionFactory getSessionFactory()
{
return sessionFactory;
}
@SuppressWarnings("unchecked")
public List <UserBean> getAllUser()
{
System.out.println("This is userDao Class");
Session session=null;
Transaction tx= null;
List<UserBean> listUserDetails = null;
try {
session= sessionFactory.openSession();
tx=session.beginTransaction();
listUserDetails = session.createQuery("from USERDATA").getResultList();
tx.commit();
}
catch(HibernateException e) {
if(tx!=null)
{
tx.rollback();
}
e.printStackTrace();
}
finally
{
session.close();
}
return listUserDetails;
}
}
Servlet 类(UserServlet.java)
package org.com.servlet;
import java.io.IOException;
import java.util.List;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.com.bean.UserBean;
import org.com.dao.UserDao;
public class UserServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private UserDao userdao = new UserDao();
protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException,
IOException
{
System.out.println("*****************************************");
System.out.println("***********Servlet***************");
System.out.println("****************************************");
List <UserBean> listALLUserDetails = userdao.getAllUser();
req.setAttribute("listALLUserDetails", listALLUserDetails);
RequestDispatcher dispathcerServlet= req.getRequestDispatcher("/ShowDetails.jsp");
dispathcerServlet.forward(req, res);
}
}
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>
<display-name>jsp-hibernate-curd</display-name>
<session-factory>
<property name="hbm2ddl.auto">update</property>
<property name="dialect">org.hibernate.dialect.Oracle9Dialect</property>
<property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name="connection.url">jdbc:oracle:thin:@localhost:1521:xe</property>
<property name="connection.username">system</property>
<property name="connection.password">admin</property>
<property name="connection.pool_size">1</property>
<property name="current_session_context_class">thread</property>
<property name="show_sql">true</property>
<mapping class="org.com.bean.UserBean" />
</session-factory>
</hibernate-configuration>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<servlet>
<servlet-name>UserServlet</servlet-name>
<servlet-class>org.com.servlet.UserServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>UserServlet</servlet-name>
<url-pattern>/user</url-pattern>
</servlet-mapping>
</web-app>
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