Hibernate实现增删改查

在Java应用总使用hibernate的步骤：
1创建hibernate的配置文件
2创建持久化类
3创建对象-关系映射文件
4通过hibernate API编写访问数据库的代码

：主键的生成方式，此为递增
：name指javabean中的属性名字，column指数据库中对应表的字段

创建持久化类：
1持久化类符合javabean的规范，包含一些属性，以及与之对应的getxxx()和setxxx()方法。
2持久化类有一个id属性，用来唯一标志Person类的每个对象。在面向对象术语中，这个id属性被称为对象标识符
3Hibernate要求持久化类必须提供一个不带参数的默认构造方法

一个SessionFactory实例对应着一个数据存储源，应用从SessionFactory中获得Session实例
Session也被成为持久化管理器，它提供了和持久化相关的操作，如添加、更新、删除、加载和查询对象
注意：此session非彼session（HttpSession）

HQL面向的是类（对象）而不是数据库中的表，这是与SQL之间的差别。

Session的get的load方法都可以获取相应的持久化对象，如果该对象存在，那么这两个方法的行为是一样的；如果该对象不存在，那么get方法会返回null而load方法则抛出异常

setAutoCommit(boolean autoCommit)：事物是否自动提交,一般设置为false（比如有5组实物，前4组成功，但第5组失败，则必须全部认为失败回滚，若为true则前4组自动提交）

我也刚刚实训过 最后做的是SSH的项目 说说我的理解和项目实际中用到的你的那些概念
action是表示层的 负责调用业务逻辑的服务组件 service是业务逻辑层的 实际上是调用了DAO的种种方法 DAO类里面就是对于数据库的操作了 .DAO是底层与数据库直接交互的部分，serivce是又对DAO进行了一次封装。而service是暴露给action的部分。
aciton里面调用service,service调用DAO

 

 

 

 

Person.hbm.xml

PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"">

 

  
  
  
  
  
  
  

  
 

 

 

hibernate.cfg.xml

          "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
          "">

   
    jdbc:mysql://localhost:3306/hibernate
    root
    yanqunqq
    com.mysql.jdbc.Driver
   
    org.hibernate.dialect.MySQL5Dialect
   
 true   
   
   
   
   

 

struts.xml

    "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
    "">
   

 
 
 
 
 
  /listAll.jsp
 
 
 
 
  /listAll.jsp
 
 
 
  /getSinglePerson.jsp
 
 
   /updatePerson.jsp
  
 
 
 
   /listAll.jsp
 
 
 

 

PersonAction.java

package com.shengsiyuan.action;

import java.util.List;

import javax.servlet.http.HttpServletRequest;

import org.apache.struts2.ServletActionContext;
import org.hibernate.sql.Update;

import com.opensymphony.xwork2.ActionSupport;
import com.shengsiyuan.model.Person;
import com.shengsiyuan.service.PersonService;
import com.shengsiyuan.service.impl.PersonServiceImpl;

public class PersonAction extends ActionSupport
{
 private int id;

 public int getId()
 {
  return id;
 }

 public void setId(int id)
 {
  this.id = id;
 }

 private String username;
 private String password;
 private int  age;

 public String getUsername()
 {
  return username;
 }

 public void setUsername(String username)
 {
  this.username = username;
 }

 public String getPassword()
 {
  return password;
 }

 public void setPassword(String password)
 {
  this.password = password;
 }

 public int getAge()
 {
  return age;
 }

 public void setAge(int age)
 {
  this.age = age;
 }

 public String savePerson() throws Exception
 {

  Person person = new Person();
  person.setUsername(username);
  person.setPassword(password);
  person.setAge(age);
  java.sql.Date registerDate = new java.sql.Date(
    new java.util.Date().getTime());
  person.setRegisterDate(registerDate);
  
  PersonService personService = new PersonServiceImpl();
  personService.savePerson(person);

  List list = personService.listAllPersons();

  HttpServletRequest request = ServletActionContext.getRequest();
  request.setAttribute("list", list);

  return SUCCESS;

 }

 public String deletePerson() throws Exception
 {
  PersonService personService = new PersonServiceImpl();
  personService.removePerson(id);

  List list = personService.listAllPersons();

  HttpServletRequest request = ServletActionContext.getRequest();
  request.setAttribute("list", list);

  return SUCCESS;

 }

 public String getSinglePerson() throws Exception
 {
  PersonService personService = new PersonServiceImpl();
  Person person = personService.getSinglePersonByid(id);
  HttpServletRequest request = ServletActionContext.getRequest();
  request.setAttribute("person", person);
  return SUCCESS;
 }

 private String updatePerson() throws Exception
 {
  PersonService personService = new PersonServiceImpl();
  Person person = personService.getSinglePersonByid(id);
  person.setPassword(password);
  person.setAge(age) ;
  personService.updatePerson(person) ;

  List list = personService.listAllPersons();

  HttpServletRequest request = ServletActionContext.getRequest();
  request.setAttribute("list", list);

  return SUCCESS;

 }
}

PersonDAO.java

package com.shengsiyuan.dao;

import java.util.List;

import com.shengsiyuan.model.Person;

public interface PersonDAO
{
 public void savePerson(Person person) ;
 public List listAllPersons() ;
 public void removePerson(Integer id) ;
 public Person getSinglePersonByid(Integer id);
 public void updatePerson(Person person) ;
}

PersonDAOImpl.java

package com.shengsiyuan.dao.impl;

import java.util.List;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

import com.shengsiyuan.dao.PersonDAO;
import com.shengsiyuan.model.Person;
import com.shengsiyuan.util.HibernateUtil;

public class PersonDAOImpl implements PersonDAO
{

 public void savePerson(Person person)
 {
  Session session = HibernateUtil.openSession();
  Transaction tx = session.beginTransaction();
  try
  {
   session.save(person);
   tx.commit();
  }
  catch (Exception ex)
  {
   if (null != tx)
   {
    tx.rollback();
   }

  }
  finally
  {
   HibernateUtil.close(session);
  }

 }

 public List listAllPersons()
 {
  // 多查看hibernate帮助文档的session接口
  Session session = HibernateUtil.openSession();
  Transaction tx = session.beginTransaction();

  List list = null;
  try
  {
   Query query = session.createQuery("from Person");// HQL语句,select
                // *可省略
                // 即为默认情况。Person为类名(不是表名)，若同名则加上包名

   list = (List) query.list();
   tx.commit();
   /*
    * 上面这行代码相当于： while(rs.next()) { Person p = new Person() ;
    * String usrname = rs.getString("username") ; String password =
    * rs.getString("password") ; ...... ... p.setUsername(username) ;
    * p.setPassword(password) ; .... .. list.add(p) ;
    * 通过hibernate.hbm.xml实现一一对应 }
    */

  }
  catch (Exception ex)
  {
   if (null != tx)
   {
    tx.rollback();
   }

  }
  finally
  {
   HibernateUtil.close(session);
  }
  return list;
 }

 public void removePerson(Integer id)
 {

  Session session = HibernateUtil.openSession();
  Transaction tx = session.beginTransaction();
  try
  {
   Person person = (Person) session.get(Person.class, id);
   session.delete(person);
   tx.commit();
  }
  catch (Exception ex)

  {
   if (null != tx)
   {
    tx.rollback();
   }

  }
  finally
  {
   HibernateUtil.close(session);
  }

 }

 public Person getSinglePersonByid(Integer id)
 {

  Session session = HibernateUtil.openSession();
  Transaction tx = session.beginTransaction();
  Person person = null;
  try
  {
   person = (Person) session.get(Person.class, id);
   tx.commit();
  }
  catch (Exception ex)

  {
   if (null != tx)
   {
    tx.rollback();
   }

  }
  finally
  {
   HibernateUtil.close(session);
  }
  return person;
 }

 public void updatePerson(Person person)
 {
  Session session = HibernateUtil.openSession();
  Transaction tx = session.beginTransaction();
  try
  {
   session.update(person) ;
   tx.commit();
  }
  catch (Exception ex)

  {
   if (null != tx)
   {
    tx.rollback();
   }

  }
  finally
  {
   HibernateUtil.close(session);
  }
  
 }

}

Person.java

package com.shengsiyuan.model;

import java.sql.Date;

public class Person
{
 private Integer id ;//int也可以
 private String username ;
 private String password ;
 private Integer age ;
 private Date registerDate ;
 public Integer getId()
 {
  return id;
 }
 public void setId(Integer id)
 {
  this.id = id;
 }
 public String getUsername()
 {
  return username;
 }
 public void setUsername(String username)
 {
  this.username = username;
 }
 public String getPassword()
 {
  return password;
 }
 public void setPassword(String password)
 {
  this.password = password;
 }
 public Integer getAge()
 {
  return age;
 }
 public void setAge(Integer age)
 {
  this.age = age;
 }
 public Date getRegisterDate()
 {
  return registerDate;
 }
 public void setRegisterDate(Date registerDate)
 {
  this.registerDate = registerDate;
 }
 

}

PersonService.java

package com.shengsiyuan.service;

import java.util.List;

import com.shengsiyuan.model.Person;

public interface PersonService
{
 public void savePerson(Person person);
 public List listAllPersons() ;
 public void removePerson(Integer id) ;
 public Person getSinglePersonByid(Integer id);
 public void updatePerson(Person person) ;
}

PersonServiceImpl.java

package com.shengsiyuan.service.impl;

import java.util.List;

import com.shengsiyuan.dao.PersonDAO;
import com.shengsiyuan.dao.impl.PersonDAOImpl;
import com.shengsiyuan.model.Person;
import com.shengsiyuan.service.PersonService;

public class PersonServiceImpl implements PersonService
{
 public void savePerson(Person person)
 {
   PersonDAO personDAO = new PersonDAOImpl() ;
   personDAO.savePerson(person) ;
 }
 public List listAllPersons()
 {

  PersonDAO personDAO = new PersonDAOImpl() ;
  return personDAO.listAllPersons() ;
 }
 public void removePerson(Integer id)
 {
  PersonDAO personDAO = new PersonDAOImpl() ;
  personDAO.removePerson(id) ;
  
 }
 public Person getSinglePersonByid(Integer id)
 {
  PersonDAO personDAO = new PersonDAOImpl() ;
  return personDAO.getSinglePersonByid(id) ;
 }
 public void updatePerson(Person person)
 {
  PersonDAO personDAO = new PersonDAOImpl() ;
  personDAO.updatePerson(person) ;
  
 }
}

HibernateUtil.java

package com.shengsiyuan.util;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

public class HibernateUtil
{
 private static SessionFactory sessionFactory ;
 static
 {
  try
  {
   sessionFactory =new Configuration().configure().buildSessionFactory() ;
   
  }
  catch(Exception ex)
  {
   ex.printStackTrace() ;
  }
  
  
  
 }
 public static Session openSession()
 {
  Session session = sessionFactory.openSession();
  return session ;
 }
 public static void close(Session session)
 {
  if(null != session)
  {
   session.close();
  }
 }
}