由于需要对Hibernate作个了解，所以写了个简单的实现
以上是大概目录
1.新建Hibernate.cfg.xml配置文件
root jdbc:mysql://localhost:3306/hiber?characterEncoding=utf8 org.hibernate.dialect.MySQLDialect mysqlJdbcDriver 123456 com.mysql.jdbc.Driver true true update
2.修改web.xml 路径映射
tHIbe userServlet servlet.userServlet userServlet *.do index.html index.htm index.jsp default.html default.htm default.jsp
3.路径跳转的servlet类
package servlet;import java.io.IOException;import java.util.ArrayList;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 com.sun.org.apache.bcel.internal.generic.Select;import entity.User;import service.UserService;import service.impl.UserServiceImpl;public class userServlet extends HttpServlet{ /** * */ private static final long serialVersionUID = 1L; UserService userService=new UserServiceImpl(); public void execute(HttpServletRequest request, HttpServletResponse response ) throws IOException{ System.out.println("进入次类"); String path = request.getServletPath(); path = path.substring(0, path.indexOf(".")); request.setCharacterEncoding("utf8"); response.setContentType("text/html;charset=utf8"); if (path.equals("/goReg")) { RequestDispatcher dispatcher=request.getRequestDispatcher("/WEB-INF/jsp/reg.jsp"); try { dispatcher.forward(request, response); } catch (ServletException e) { // TODO Auto-generated catch block e.printStackTrace(); } }else if(path.equals("/reg")){ regUser(request,response); try { request.getRequestDispatcher("/WEB-INF/jsp/index.jsp").forward(request, response); } catch (ServletException e) { // TODO Auto-generated catch block e.printStackTrace(); } }else if(path.equals("/select")){ select(request,response); try { request.getRequestDispatcher("/WEB-INF/jsp/index.jsp").forward(request, response); } catch (ServletException e) { // TODO Auto-generated catch block e.printStackTrace(); } }else if(path.equals("/delete")){ delete(request,response); try { request.getRequestDispatcher("/WEB-INF/jsp/index.jsp").forward(request, response); } catch (Exception e) { e.printStackTrace(); } } } public void regUser(HttpServletRequest req,HttpServletResponse resp){ System.out.println("进行注册"); String name=req.getParameter("name"); String pwd=req.getParameter("pwd"); User user=new User(); user.setName(name); user.setPwd(pwd); userService.addUser(user); req.setAttribute("user", user); } public void select(HttpServletRequest req,HttpServletResponse resp){ System.out.println("查询中"); List list=new ArrayList<>(); list=userService.select(); req.setAttribute("list", list); } public void delete(HttpServletRequest req,HttpServletResponse resp){ Integer id=Integer.parseInt(req.getParameter("name")); int result=userService.delete(id); if(result==1){ req.setAttribute("msg", "成功kill"); } System.out.println(result); } @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { System.out.println("haha "); execute(req,resp); } @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { // TODO Auto-generated method stub doGet(req, resp); }} 4.新建Hibernate工具类（主要用来在dao的实现类里面创建session、关闭session等）
package util;import org.hibernate.HibernateException;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.cfg.Configuration;public class HibernateUtil {private static final SessionFactory sessionFactory; static { try { Configuration config = new Configuration().configure("hibernate.cfg.xml"); sessionFactory = config.buildSessionFactory(); } catch(Throwable e) { throw new ExceptionInInitializerError(e); } } public static final ThreadLocal session = new ThreadLocal(); public static Session currentSession() throws HibernateException { Session s = (Session)session.get(); //Open a new Session,if this Thread has none yet if(s == null || !s.isOpen()) { s = sessionFactory.openSession(); session.set(s); } return s; } public static void closeSession() throws HibernateException { Session s = (Session)session.get(); session.set(null); if(s != null) s.close(); }} 5.dao层实现类代码参考
package dao.impl;import java.util.List;import org.hibernate.Query;import org.hibernate.Session;import org.hibernate.Transaction;import dao.UserDao;import entity.User;import util.HibernateUtil;public class UserDaoImpl implements UserDao { @Override public void addUser(User user) { // TODO Auto-generated method stub Session session = HibernateUtil.currentSession(); Transaction tx=session.beginTransaction(); try { session.save(user);//保存次酒类对象 tx.commit();//提交到数据库 session.close(); } catch (Exception e) { e.printStackTrace(); tx.rollback(); } } @Override public List select() { Session session = HibernateUtil.currentSession(); //Transaction tx=session.beginTransaction(); List list=null; try { String hql="from User";//使用命名参数，推荐使用，易读。 Query query=session.createQuery(hql); list=query.list(); //tx.commit();//提交到数据库 session.close(); return list; } catch (Exception e) { e.printStackTrace(); } return list; } @Override public int delete(Integer id) { Session session=HibernateUtil.currentSession(); Transaction tx=session.beginTransaction(); try { User user=(User)session.get(User.class, id); session.delete(user); tx.commit(); session.close(); } catch (Exception e) { e.printStackTrace(); tx.rollback(); return 0; } return 1; }} 6.User实体类的映射文件User.hbm.xml，和数据的关联文件（需要在Hibernate.cfg.xml配置文件中引入）
7.User实体类（注意要实现 implements Serializable）
package entity;import java.io.Serializable;/** * 持久化user类 * @author Administrator * */public class User implements Serializable{ private int id; private String name; private String pwd; public User(int id, String name, String pwd) { super(); this.id = id; this.name = name; this.pwd = pwd; } public User() { } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getPwd() { return pwd; } public void setPwd(String pwd) { this.pwd = pwd; } } 8.jsp页面
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>主页 欢迎你：${suser.name},你将走向最强王者之路点击下方按钮：最强王者是：${list.get(1).name}看我的${msg}
你已成为最强王者请修改你的名称：
在项目遇到的问题有：
1.启动tomcat时 报无法启动的错误，错误可能在xml配置文件
2.xml配置的路径跳转不能跳转，同样的代码，重新建项目后又可以了，不知道什么原因