hibernate新手日记

1）通过Maven的pom.xml引用hibernate的jar包

<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-core</artifactId>
    <!-- <version>5.1.3.Final</version> -->
    <version>4.3.9.Final</version> 
</dependency>

hibernate-core-

2）hibernate.cfg.xml文件（官网可以copy到）

<?xml version='1.0' encoding='utf-8'?>
<!--
  ~ Hibernate, Relational Persistence for Idiomatic Java
  ~
  ~ License: GNU Lesser General Public License (LGPL), version 2.1 or later.
  ~ See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
  -->
<!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>

        <!-- Database connection settings -->
        <!-- 所连接的数据库信息 -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">url?useUnicode=true&amp;characterEncoding=utf-8</property>
        <property name="connection.username">username</property>
        <property name="connection.password">password</property>

        <!-- JDBC connection pool (use the built-in) 
                链接池的大小-->
        <property name="connection.pool_size">5</property>

        <!-- SQL dialect -->
        <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>

        <!-- Disable the second-level cache  -->
        <property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>

        <!-- Echo all executed SQL to stdout 标准输出-->
        <property name="show_sql">true</property>

        <!-- Drop and re-create the database schema on startup 
                是否自动生成表
        <property name="hbm2ddl.auto">create</property>-->

        <!-- 通过包路径来寻找文件，xml文件使用 -->
        <mapping resource="。。。/hibernate/entity/User.hbm.xml"/>
        <!-- 通过类路径来寻找文件，注解使用 -->
        <mapping class="。。。.hibernate.entity.AnnoUser"/>

    </session-factory>

</hibernate-configuration>

3)实体类(entity)

*不使用注解的实体类User.java

//配置信息都在resouces下的同一目录下的User.hbm.xml
public class User{
    private BigInteger id;
    private String name;
    private String account;
    private String password;
    private BigInteger organizationId;

User.hm.xml

<?xml version="1.0"?>

<!--
  ~ Hibernate, Relational Persistence for Idiomatic Java
  ~
  ~ License: GNU Lesser General Public License (LGPL), version 2.1 or later.
  ~ See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
  -->
<!DOCTYPE hibernate-mapping PUBLIC
        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<!-- 通过包路径扫描实体类 -->
<hibernate-mapping package="。。。.hibernate.entity">

    <class name="User" table="user">
        <id name="id" column="id">
            <generator class="assigned"/>
        </id>
        <property name="name"/>
        <property name="account"/>
        <property name="password"/>
        
        <!-- 属性名和字段名一致用下列代码表示 
        <property name="title"/>
        属性名和字段名不一致用下列代码表示 
        <property name="title" column="数据库字段名"/>
        -->
    </class>

</hibernate-mapping>
                

*使用注解的实体类AnnoUser

//表示为实体类
@Entity
//表示连接的数据库名称
@Table(name="user")
public class AnnoUser{
    //表示为主键
    @Id
    private BigInteger id;
    //表示连接的字段名称
    @Column(name="name")
    private String name;
    
    @Column(name="account")
    private String account;
    
    @Column(name="password")
    private String password;
        //不和数据库进行映射
    @Transient
    private BigInteger organizationId;

4) 单元测试（实现对数据库简单的增删改查）

public class Hibernate4Annotest {
    
    private SessionFactory sessionFactory;
    
    @Before
    public void before(){
        //(1)加载配置(默认CLASSPATH下的hibernate.cfg.xml)
        Configuration conf = new Configuration().configure();
        
        sessionFactory = conf.buildSessionFactory(
                new StandardServiceRegistryBuilder().applySettings(conf.getProperties()).build());
        
        
        /*//(2)通过Configuration创建StandardServiceRegistryBuilder实例
        //由StandardServiceRegistryBuilder构建StandardServiceRegistry实例
        StandardServiceRegistryBuilder serviceRegistryBuilder = 
                new StandardServiceRegistryBuilder().applySettings(conf.getProperties());
        StandardServiceRegistry serviceRegistry = serviceRegistryBuilder.build();
        
        //(3)通过StandardServiceRegistry实例构建Session工厂
        sessionFactory = conf.buildSessionFactory(serviceRegistry);*/
        
    }
    
    @After
    public void after(){
        sessionFactory.close();
    }
    
    @Test
    @Ignore
        //查
    public void select(){
        Session session = sessionFactory.openSession();
        Object user = session.get(User.class,new BigInteger("100000"));
        System.out.println(user);
    }
    
    @Test
    @Ignore
        //改1
        //修改有两种方式，一种是查到后，对源数据进行覆盖
        //一种是根据id寻找源数据进行修改
    public void update(){
        Session session = sessionFactory.openSession();
        //开启一个事务
        Transaction tr = session.beginTransaction();
        User user = new User();
        user.setId(new BigInteger("100001"));
        user.setAccount("hiber4");
        user.setContactPhone("11111111111");
        user.setCreateTime(new Date());
        user.setName("hibernate");
        user.setPassword("nate");
        user.setState(1);
        
        session.update(user);
        tr.commit();
    }
    
    @Test
    @Ignore
        //改2
    public void update2(){
        Session session = sessionFactory.openSession();
        //开启一个事务
        Transaction tr = session.beginTransaction();
        User user = (User)session.get(User.class,new BigInteger("100001"));
        user.setAccount("hiber3");
        user.setContactPhone("22222222222");
        user.setCreateTime(new Date());
        user.setName("hibernate");
        user.setPassword("nate");
        user.setState(1);
        
        //session.flush();
        tr.commit();
    }
    
    @Test
    @Ignore
        //删
    public void delete(){
        Session session = sessionFactory.openSession();
        //开启一个事务
        Transaction tr = session.beginTransaction();
        User user = new User();
        user.setId(new BigInteger("100000"));
        
        session.delete(user);
        tr.commit();
    }
    
    @Test
    @Ignore
        //增
    public void add(){
        Session session = sessionFactory.openSession();
        //开启一个事务
        Transaction tr = session.beginTransaction();
        try {
            User user = new User();
            user.setId(new BigInteger("100002"));
            user.setAccount("hiber2");
            user.setContactPhone("11111111111");
            user.setCreateTime(new Date());
            user.setName("hibernate");
            user.setPassword("nate");
            user.setState(1);
            //保存对象
            session.save(user);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            tr.rollback();
        }
        //事务提交
        tr.commit();
        //session关闭
        session.close();
    }

}