hibernate(二)annotation第一个示例

时间:2023-03-09 08:28:16
hibernate(二)annotation第一个示例

一、在数据库中创建teacher表(数据库hibernate)

create table teache(
id int auto_increment primary key,
name varchar(20),
title varchar(20)
);

二、创建model

在cn.orlion.hibernate.model下创建实体类Teacher(注意添加注解,一开始只添加了@Id,然后抛出异常,后来又加上了@GeneratedValue(strategy = GenerationType.AUTO))

package cn.orlion.hibernate.model;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id; @Entity
public class Teacher{ private int id; private String name; private String title;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
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 getTitle() {
return title;
} public void setTitle(String title) {
this.title = title;
}
}

三、在配置文件中配置类:

在hibernate.cfg.xml中添加下面一行

<mapping class="cn.orlion.hibernate.model.Teacher" />

OK,配置完成写一个测试:

package cn.orlion.test;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.cfg.Configuration; import cn.orlion.hibernate.model.Teacher; public class TeacherTest { public static void main(String[] args){ Teacher t = new Teacher(); t.setName("test1");
t.setTitle("title1"); Configuration cfg = new AnnotationConfiguration(); SessionFactory sf = cfg.configure().buildSessionFactory(); Session session = sf.openSession(); session.beginTransaction();
session.save(t);
session.getTransaction().commit(); session.close(); sf.close();
}
}

运行可以看到数据库中添加了一条记录。

hibernate(二)annotation第一个示例