hibernate 记录2

记录让头发掉的少。

简单写一个hibernate实现数据库操作Demo；


1.首先将hibernate-jars下载下来，创建java项目将依赖引入到项目中。

2.创建实体类：

public class Employee {  
    private int id;  
    private String firstName,lastName;  

    public int getId() {  
        return id;  
    }  
    public void setId(int id) {  
        this.id = id;  
    }  
    public String getFirstName() {  
        return firstName;  
    }  
    public void setFirstName(String firstName) {  
        this.firstName = firstName;  
    }  
    public String getLastName() {  
        return lastName;  
    }  
    public void setLastName(String lastName) {  
        this.lastName = lastName;  
    }  

}

3.创建持久化类的映射文件（映射文件用于数据库中数据的持久化）

<?xml version='1.0' encoding='UTF-8'?>  
<!DOCTYPE hibernate-mapping PUBLIC  
 "-//Hibernate/Hibernate Mapping DTD 3.0//EN"  
 "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">  

 <hibernate-mapping>  
  <!--实体类完全地址，对象数据库的表-->
  <class name="com.yiibai.mypackage.Employee" table="tb_employee">  
    <id name="id">  
     <generator class="assigned"></generator>  
    </id>  

    <property name="firstName"></property>  
    <property name="lastName"></property>  

  </class>  

4.创建配置文件
   配置文件的主要内容：connection_url(数据库连接地址)，diver_class(数据库驱动),username:数据库用户名，password：登录密码  等。mapper标签中是程序的会话管理。

<?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">

<!-- Generated by MyEclipse Hibernate Tools. -->
<hibernate-configuration>

    <session-factory>

        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/test</property>
        <property name="connection.username">root</property>
        <property name="connection.password">123456</property>
        <property name="dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>
        <property name="show_sql">true</property>
        <mapping resource="employee.hbm.xml"/>  
    </session-factory>

5.创建操作类

 

ublic class StoreData {  
    public static void main(String[] args) {  

        //创建连接  
        Configuration cfg=new Configuration();  
        cfg.configure("hibernate.cfg.xml");//populates the data of the configuration file  

        //创建会话工厂  
        SessionFactory factory=cfg.buildSessionFactory();  

        //创建会话 
        Session session=factory.openSession();  

        //创建事务
        Transaction t=session.beginTransaction();  

        Employee e1=new Employee();
        e1.setId(100);
        e1.setFirstName("Max");
        e1.setLastName("Su");

        session.persist(e1);//持久化数据

        t.commit();//提交事务
        session.close();  //关闭事务

        System.out.println("successfully saved");  

    }  

6. 在数据库中创建tb_employee

CREATE TABLE `tb_employee` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `firstName` varchar(32) NOT NULL DEFAULT '',
  `lastName` varchar(32) NOT NULL DEFAULT '',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=101 DEFAULT CHARSET=utf8;