Java/Hibernate/Retrieve
Версия от 18:01, 31 мая 2010; (обсуждение)
Simple Retrieve
/////////////////////////////////////////////////////////////////////////
import java.util.Date;
import org.hibernate.Session;
import org.hibernate.Transaction;
public class SimpleRetrieveTest {
public static void main(String[] args) {
HibernateUtil.setup("create table EVENTS ( EVENT_ID int, EVENT_DATE date, title VARCHAR);");
// hibernate code start
Session session = HibernateUtil.currentSession();
Transaction tx = session.beginTransaction();
Event theEvent = new Event();
theEvent.setTitle("My Event");
theEvent.setDate(new Date());
session.save(theEvent);
tx.rumit();
HibernateUtil.closeSession();
HibernateUtil.sessionFactory.close();
// saved then retrieve it
session = HibernateUtil.currentSession();
tx = session.beginTransaction();
Event e = (Event)session.get(Event.class, new Long(1));
System.out.println(e);
tx.rumit();
HibernateUtil.closeSession();
HibernateUtil.sessionFactory.close();
// hibernate code end
HibernateUtil.checkData("select * from events;");
}
}
/////////////////////////////////////////////////////////////////////////
<?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="Event" table="EVENTS">
<id name="id" column="EVENT_ID">
<generator class="increment"/>
</id>
<property name="date" type="timestamp" column="EVENT_DATE"/>
<property name="title"/>
</class>
<class name="EventWithAttendee" table="eventwithattendee">
<id name="id" column="uid" type="long" unsaved-value="null">
<generator class="native"/>
</id>
<property name="name" type="string" length="100"/>
<property name="startDate" column="start_date"
type="date"/>
<property name="duration" type="integer"/>
<many-to-one name="location" column="location_id"
class="Location"/>
<set name="attendees" cascade="all">
<key column="event_id"/>
<one-to-many class="EventAttendee"/>
</set>
</class>
<class name="EventAttendee" table="attendees">
<id name="id" column="uid" type="long">
<generator class="native"/>
</id>
<property name="firstName" type="string" length="20"/>
<property name="lastName" type="string" length="20"/>
</class>
<class name="Location" table="locations">
<id name="id" column="uid" type="long">
<generator class="native"/>
</id>
<property name="name" type="string"/>
<property name="address" type="string"/>
</class>
</hibernate-mapping>
/////////////////////////////////////////////////////////////////////////
import java.util.Date;
public class Event {
private Long id;
private String title;
private Date date;
Event() {
}
public Long getId() {
return id;
}
private void setId(Long id) {
this.id = id;
}
public Date getDate() {
return date;
}
public void setDate(Date date) {
this.date = date;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String toString() {
return "ID:" + id + "\nTitle:" + title + "\nDate:" + date;
}
}
/////////////////////////////////////////////////////////////////////////
<?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">org.hsqldb.jdbcDriver</property>
<property name="connection.url">jdbc:hsqldb:data/tutorial</property>
<property name="connection.username">sa</property>
<property name="connection.password"></property>
<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">1</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.HSQLDialect</property>
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<mapping resource="Event.hbm.xml"/>
</session-factory>
</hibernate-configuration>