对hibernate的学习之用配置文件和annotation配置的区别

1.用配置文件配置hibernate

①

基础类：

package com.bjsxt.hibernate;

public class Student {
private int id;
private String name;
private int age;
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 int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}

}

②

和基础类在同一个包下面映射文件

Student.hbm.xml

<?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.bjsxt.hibernate.Student">
<id name="id" />
<property name="name" />
<property name="age" />

    </class>

</hibernate-mapping>

③

在根目录下的配置映射文件

hibernate.cfg.xml

<?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>

        <!-- Database connection settings -->

        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>

        <property name="connection.url">jdbc:mysql://localhost/hibernate</property>

        <property name="connection.username">root</property>

        <property name="connection.password">bjsxt</property>

        <!-- JDBC connection pool (use the built-in) -->

        <property name="connection.pool_size">1</property>

        <!-- SQL dialect -->

        <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

        <!-- Enable Hibernate's automatic session context management -->

        <property name="current_session_context_class">thread</property>

        <!-- Disable the second-level cache  -->

        <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

        <!-- Echo all executed SQL to stdout -->

        <property name="show_sql">true</property>

        <!-- Drop and re-create the database schema on startup -->

        <property name="hbm2ddl.auto">update</property>

        <mapping resource="com/bjsxt/hibernate/Student.hbm.xml"/>

    </session-factory>

</hibernate-configuration>

④测试类

package com.bjsxt.hibernate;

import org.hibernate.Session;

import org.hibernate.SessionFactory;

import org.hibernate.cfg.AnnotationConfiguration;

public class Test {
public static void main(String[] args) {
Student s = new Student();
s.setId(1);
s.setName("zhangsan");
s.setAge(8);

SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();
Session session = sessionFactory.getCurrentSession();
session.beginTransaction();
session.save(s);
session.getTransaction().commit();

}

}

2.用annotation配置

①基础类

package com.bjsxt.hibernate;

import javax.persistence.Entity;

import javax.persistence.Id;

@Entity

public class Teacher {
private int id;
private String name;
private String title;

@Id
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;
}

}

②和基础类在同一个包下面映射文件

hibernate.cfg.xml

<?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>

        <!-- Database connection settings -->

        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>

        <property name="connection.url">jdbc:mysql://localhost/hibernate</property>

        <property name="connection.username">root</property>

        <property name="connection.password">bjsxt</property>

        <!-- JDBC connection pool (use the built-in) -->

        <property name="connection.pool_size">1</property>

        <!-- SQL dialect -->

        <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

        <!-- Enable Hibernate's automatic session context management -->

        <property name="current_session_context_class">thread</property>

        <!-- Disable the second-level cache  -->

        <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

        <!-- Echo all executed SQL to stdout -->

        <property name="show_sql">true</property>

        <!-- Drop and re-create the database schema on startup -->

        <property name="hbm2ddl.auto">update</property>

<mapping class="com.bjsxt.hibernate.Teacher"/>

    </session-factory>

</hibernate-configuration>

③测试类

package com.bjsxt.hibernate;

import org.hibernate.Session;

import org.hibernate.SessionFactory;

import org.hibernate.cfg.AnnotationConfiguration;

public class TeacherTest {
public static void main(String[] args) {
Teacher t = new Teacher();
t.setId(1);
t.setName("t1");
t.setTitle("middle");

SessionFactory sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
Session session = sessionFactory.getCurrentSession();
session.beginTransaction();
session.save(t);
session.getTransaction().commit();
}

}