Hibernate第一个例子

Posted 2020-10-18 努力奋斗吧

 

大配置文件

<?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">
<hibernate-configuration>
    <session-factory>
        <!-- 指定数据库所用到的驱动 -->
        <property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
        <!-- 指定数据库链接的url，hibernate链接的数据库名 -->
        <property name="connection.url">jdbc:oracle:thin:@localhost:1521:orcl</property>
        <!-- 指定连接数据库的用户名 -->
        <property name="connection.username">root</property>
        <!-- 指定连接数据库的用户口令 -->
        <property name="connection.password">root</property>
        <!--格式化sql -->
        <property name="format_sql ">true</property>
        <!-- 指定数据库方言 -->
        <property name="dialect">org.hibernate.dialect.Oracle10gDialect</property>
        <!-- 根据需要自动创建数据库表 -->
        <property name="hbm2ddl.auto">update</property>
        <!-- 打印sql 控制台-->
        <property name="show_sql">true</property>
        <!--关联小配置文件-->
        <mapping resource="cn/sjl/entity/School.hbm.xml"></mapping>
    </session-factory>
</hibernate-configuration>

实体类

public class School {
    private int schoolid;
    private String schoolname;

    public int getSchoolid() {
        return schoolid;
    }
    public void setSchoolid(int schoolid) {this.schoolid = schoolid;}
    
    public String getSchoolname() {
        return schoolname;
    }
    public void setSchoolname(String schoolname) {
        this.schoolname = schoolname;
    }
}


小配置文件

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<!-- 映射文件开始 -->
<hibernate-mapping package="cn.sjl.entity">
    <class name="School" table="School">
       <id name="schoolid" column="schoolid">
           <generator class="native"></generator>
       </id>
        <property name="schoolname" column="schoolname"></property>
    </class>
</hibernate-mapping>


测试类

//get方法
@Test
public  void  test02(){
    //构造Configuration对象，读取大配置文件
    Configuration cfg=new Configuration().configure();
    //构造工厂
    SessionFactory factory=cfg.buildSessionFactory();
    //Session对象   openSession()
    Session session = factory.openSession();
    School school1 = session.get(School.class, 2);
    System.out.println("学校名称："+school1.getSchoolname());
    System.out.println(school1);
    //关闭session
    session.close();
}