hibernate入门实例

男娘i 2022-05-14 13:57 240阅读 0赞

\#\#\#Hibernate5简单应用实例

1.下载Hibernate所需jar包  
2.新建java项目，并导入jar包  
3.新建User.java文件，User类的属性于数据库表的字段一一对应

-- ----------------------------
    -- Table structure for `p_user`
    -- ----------------------------
    DROP TABLE IF EXISTS `p_user`;
    CREATE TABLE `p_user` (
      `user_id` int(11) NOT NULL AUTO_INCREMENT,
      `user_name` varchar(20) DEFAULT NULL,
      `user_pwd` varchar(20) DEFAULT NULL,
      `user_email` varchar(30) DEFAULT NULL,
      PRIMARY KEY (`user_id`)
    ) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;
    
    -- ----------------------------
    -- Records of p_user
    -- ----------------------------
    INSERT INTO `p_user` VALUES ('1', 'yxc', '123456', 'for@163.com');
    INSERT INTO `p_user` VALUES ('2', '张飞', '123456', '1324688478@qq.com');
    INSERT INTO `p_user` VALUES ('5', '李四', '123456', null);
    INSERT INTO `p_user` VALUES ('6', 'LeBronJames', '123456', '1324688478@qq.com');

package com.model;
    
    public class User {
        
        private int userId;  //用户编号
        private String userName; //用户名
        private String userPwd;  //密码
        private String userEmail;//邮箱
    
        public int getUserId() {
        
            return userId;
        }
    
        public String getUserName() {
        
            return userName;
        }
    
        public String getUserPwd() {
        
            return userPwd;
        }
    
        public String getUserEmail() {
        
            return userEmail;
        }
    
        public void setUserId(int userId) {
        
            this.userId = userId;
        }
    
        public void setUserName(String userName) {
        
            this.userName = userName;
        }
    
        public void setUserPwd(String userPwd) {
        
            this.userPwd = userPwd;
        }
    
        public void setUserEmail(String userEmail) {
        
            this.userEmail = userEmail;
        }
    }

4.新建User.hbm.xml文件,建立User类和p\_user表的映射关系

<?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>
        <class name="com.model.User" table="p_user" lazy="false">
            <id name="userId" column="user_id">
                <generator class="increment"/>
            </id>
    
            <property name="userName" type="java.lang.String">
                <column name="user_name" length="30"/>
            </property>
            
            <property name="userPwd" type="java.lang.String">
                <column name="user_pwd"/>
            </property>
            <property name="userEmail" type="java.lang.String">
                <column name="user_email"/>
            </property>
        </class>
    
    </hibernate-mapping>

5.在src目录下新建hibernate.cfg.xml文件

<!DOCTYPE hibernate-configuration PUBLIC
              "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
              "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
    
    <hibernate-configuration>
        <session-factory>
        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.connection.password">Root</property>
        <property name="hibernate.connection.url">jdbc:mysql://localhost/pblog</property>
        <property name="hibernate.show_sql">true</property>
        <mapping resource="com/model/User.hbm.xml"/>
        <mapping class="com.model.User"/>
        </session-factory>
    </hibernate-configuration>

6.创建HibernateUtil工具类，用来获取hibernate的session对象

package com.utils;
    
    import org.hibernate.Session;
    import org.hibernate.SessionFactory;
    import org.hibernate.cfg.Configuration;
    import org.hibernate.service.ServiceRegistry;
    import org.hibernate.service.ServiceRegistryBuilder;
    
    public class HibernateUtil {
        
        private static SessionFactory factory = null;
    
        static {
        
            Configuration configuration = new Configuration().configure();
            ServiceRegistry serviceRegistry = new ServiceRegistryBuilder()
                    .applySettings(configuration.getProperties())
                    .buildServiceRegistry();
            factory = configuration.buildSessionFactory(serviceRegistry);
        }
    
        public static Session getSession() {
        
            return factory.openSession();
        }
    }

7.创建UserDao.java文件，对User进行增删改查操作

package com.dao;
    
    import com.model.User;
    import com.utils.HibernateUtil;
    import org.hibernate.Session;
    import org.hibernate.Transaction;
    
    public class UserDao {
        
        public User getUserByID(int id)
        {
        
            Session session = HibernateUtil.getSession();
            User user = (User)session.get(User.class, id);
            session.close();
            return user;
        }
    
        public void addUser(User user) {
        
            Session session = HibernateUtil.getSession();
            Transaction ts = session.beginTransaction();
            session.save(user);
            ts.commit();
            session.close();
        }
    
        public void updateUser(User user) {
        
            Session session = HibernateUtil.getSession();
            Transaction ts = session.beginTransaction();
            session.saveOrUpdate(user);
            ts.commit();
            session.close();
        }
    
        public void deleteUser(User user) {
        
            Session session = HibernateUtil.getSession();
            Transaction ts = session.beginTransaction();
            session.delete(user);
            ts.commit();
            session.close();
        }
    }

8.测试运行

package com.test;
    
    import com.dao.UserDao;
    import com.model.User;
    
    public class Test {
        
        public static void main(String[] args) {
        
    
            User user=new User();
            user.setUserName("LeBronJames");
            user.setUserPwd("123456");
            user.setUserEmail("1324688478@qq.com");
    
            UserDao userDao=new UserDao();
            userDao.addUser(user);
        }
    }

查看控制台打印信息

Hibernate: select max(user_id) from p_user
    Hibernate: insert into p_user (user_name, user_pwd, user_email, user_id) values (?, ?, ?, ?)

实现了往数据库中插入一条记录的操作  
获取源码地址[https://github.com/yangxuechen/ssh-learning-example/tree/master/HibernateTest][https_github.com_yangxuechen_ssh-learning-example_tree_master_HibernateTest]

[https_github.com_yangxuechen_ssh-learning-example_tree_master_HibernateTest]: https://github.com/yangxuechen/ssh-learning-example/tree/master/HibernateTest