Hibernate 開發流程

時間 2019-11-09

原文原文鏈接

Hibernate 開發流程java

1、導入相應的包
   一、hibernate安裝文件夾中的lib->required中的包
   二、導入log4j
   三、導入數據庫驅動mysql

2、建立hibernate的配置文件
在src的目錄下建立相應的hibernate.cfg.xml在這個文件中加入相應的數據庫基本信息的配置
在hibernate.cfg.xml的配置文件中首先須要配置相應的數據庫基本鏈接sql

<hibernate-configuration>
    <session-factory>
    <!-- hibernate的方言，用來肯定鏈接的數據庫 -->
        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
    <!-- 數據庫的鏈接類 -->
        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
    <!-- 數據庫的鏈接字符串和用戶名密碼 -->
        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/itat_hibernate</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.connection.password">123456</property>
    <!-- 在使用hibernate時會顯示相應的SQL -->
        <property name="show_sql">true</property>
    <!-- 會自動完成類到數據表的轉換 -->
        <property name="hibernate.hbm2ddl.auto">update</property>
    <!-- 加入實體類的映射文件 -->    
    </session-factory>
</hibernate-configuration>

3、建立實體類數據庫

package org.test.model;
import java.util.Date;

public class User {
    
    private int id;
    private String username;
    private String password;
    private String nickname;
    private Date born;
    
    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 getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    public String getNickname() {
        return nickname;
    }
    public void setNickname(String nickname) {
        this.nickname = nickname;
    }
    public Date getBorn() {
        return born;
    }
    public void setBorn(Date born) {
        this.born = born;
    }
    @Override
    public String toString() {
        return "User [id=" + id + ", username=" + username + ", password="
                + password + ", nickname=" + nickname + ", born=" + born + "]";
    }
}

4、在實體類的包中建立相應的hbm文件，用來指定實體類和數據庫映射關係安全

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

<hibernate-mapping package="org.test.model">
    <class name="User" table="t_user">
        <id name="id">
            <generator class="native"/>
        </id>
        <property name="username"/>
        <property name="password"/>
        <property name="nickname"/>
        <property name="born" type="timestamp"/>
    </class>
</hibernate-mapping>

5、將配置文件添加到hibernate的cfg的配置文件中session

<hibernate-configuration>
    <session-factory>
    <!-- hibernate的方言，用來肯定鏈接的數據庫 -->
        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
    <!-- 數據庫的鏈接類 -->
        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
    <!-- 數據庫的鏈接字符串和用戶名密碼 -->
        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/itat_hibernate</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.connection.password">123456</property>
    <!-- 在使用hibernate時會顯示相應的SQL -->
        <property name="show_sql">true</property>
    <!-- 會自動完成類到數據表的轉換 -->
        <property name="hibernate.hbm2ddl.auto">update</property>
    <!-- 加入實體類的映射文件 -->    
        <mapping resource="org/test/model/User.hbm.xml"/>
    </session-factory>
</hibernate-configuration>

6、建立SessionFactory,SessionFactory是線程安全，因此整個SessionFactory應該基於單例的模式來建立
       Configuration cfg = new Configuration().configure();
       //cfg.buildSessionFactory();//在hibernate3中都是使用該種方法建立，可是在4中被禁用了
       ServiceRegistry serviceRegistry = new ServiceRegistryBuilder()
                           .applySettings(cfg.getProperties()).buildServiceRegistry();
       SessionFactory factory = cfg.buildSessionFactory(serviceRegistry);app

7、建立session
Session session = factory.openSession();ide

8、經過session來進行各類操做
   如下代碼完成了對象的添加操做
       try {
           session = factory.openSession();
           //開啓事務
           session.beginTransaction();
           User u = new User();
           u.setNickname("張三");
           u.setPassword("123");
           u.setUsername("zhangsan");
           u.setBorn(new Date());
           session.save(u);
           //提交事務
           session.getTransaction().commit();
       } catch (HibernateException e) {
           e.printStackTrace();
           if(session!=null) session.getTransaction().rollback();
       } finally {
           if(session!=null) session.close();
       }ui

完整Test類this

package org.test.test;


import java.util.Date;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
import org.junit.Test;
import org.test.model.User;

public class TestFirst {

    @Test
    public void test01() {
        Configuration cfg = new Configuration().configure();
        //cfg.buildSessionFactory();//在hibernate3中都是使用該種方法建立，可是在4中被禁用了
        ServiceRegistry serviceRegistry = new ServiceRegistryBuilder()
                            .applySettings(cfg.getProperties()).buildServiceRegistry();
        SessionFactory factory = cfg.buildSessionFactory(serviceRegistry);
        Session session = null;
        try {
            session = factory.openSession();
            //開啓事務
            session.beginTransaction();
            User u = new User();
            u.setNickname("張三");
            u.setPassword("123");
            u.setUsername("zhangsan");
            u.setBorn(new Date());
            session.save(u);
            //提交事務
            session.getTransaction().commit();
        } catch (HibernateException e) {
            e.printStackTrace();
            if(session!=null) session.getTransaction().rollback();
        } finally {
            if(session!=null) session.close();
        }
    }

}