Java/Hibernate/DAO Simple DAO — различия между версиями

Материал из Java эксперт
Перейти к: навигация, поиск
 
м (1 версия)
 
(нет различий)

Текущая версия на 06:51, 1 июня 2010

Simple Dao Create

/////////////////////////////////////////////////////////////////////////
import java.util.*;
import org.hibernate.*;
import org.hibernate.criterion.*;
public class Main {
  
  
  public static void main(String[] args) {
    HibernateUtil.setup("create table EVENTS ( uid int, name VARCHAR, start_Date date, duration int);");
    
    // hibernate code start

        SimpleEventDao eventDao = new SimpleEventDao();
        Event event = new Event();
        event.setName("Create an Event");
        eventDao.create(event);
        
        
        

        Event event2 = null;
    Session session = HibernateUtil.currentSession();
    Transaction tx = session.beginTransaction();
        event2 = (Event) session.load(Event.class, event.getId());
        System.out.println(event.getName());
        System.out.println(event2.getName());
        tx.rumit();
    HibernateUtil.closeSession();
    HibernateUtil.sessionFactory.close();
        HibernateUtil.checkData("select uid, name from events");        
    // hibernate code end
  }
  
}

/////////////////////////////////////////////////////////////////////////
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.Query;
import org.apache.rumons.logging.Log;
import org.apache.rumons.logging.LogFactory;
import java.util.List;
public class SimpleEventDao {
    Log log = LogFactory.getLog(SimpleEventDao.class);
    private Session session;
    private Transaction tx;
    public SimpleEventDao() {
        HibernateFactory.buildIfNeeded();
    }
    /**
     * Insert a new Event into the database.
     * @param event
     */
    public void create(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.save(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }

    /**
     * Delete a detached Event from the database.
     * @param event
     */
    public void delete(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.delete(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }
    /**
     * Find an Event by its primary key.
     * @param id
     * @return
     */
    public Event find(Long id) throws DataAccessLayerException {
        Event event = null;
        try {
            startOperation();
            event = (Event) session.load(Event.class, id);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return event;
    }
    /**
     * Updates the state of a detached Event.
     *
     * @param event
     */
    public void update(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.update(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }
    /**
     * Finds all Events in the database.
     * @return
     */
    public List findAll() throws DataAccessLayerException{
        List events = null;
        try {
            startOperation();
            Query query = session.createQuery("from Event");
            events =  query.list();
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return events;
    }
    private void handleException(HibernateException e) throws DataAccessLayerException {
        HibernateFactory.rollback(tx);
        throw new DataAccessLayerException(e);
    }
    private void startOperation() throws HibernateException {
        session = HibernateFactory.openSession();
        tx = session.beginTransaction();
    }
}


/////////////////////////////////////////////////////////////////////////
/**
 * Represents Exceptions thrown by the Data Access Layer.
 */
public class DataAccessLayerException extends RuntimeException {
    public DataAccessLayerException() {
    }
    public DataAccessLayerException(String message) {
        super(message);
    }
    public DataAccessLayerException(Throwable cause) {
        super(cause);
    }
    public DataAccessLayerException(String message, Throwable cause) {
        super(message, cause);
    }
}

/////////////////////////////////////////////////////////////////////////
<?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="uid" type="long">
            <generator class="increment"/>
        </id>
        <property name="name" type="string"/>
        <property name="startDate" column="start_date" type="date"/>
        <property name="duration" type="integer"/>
    </class>
</hibernate-mapping>


/////////////////////////////////////////////////////////////////////////
import java.io.Serializable;
import java.util.Date;
import java.util.Set;
import java.util.LinkedHashSet;
public class Event implements Serializable {
    private Long id;
    private int duration;
    private String name;
    private Date startDate;
    public Event() {
    }
    public Event(String name) {
        this.name = name;
    }
    /**
     * @hibernate.id generator-class="native" column="uid"
     * @return
     */
    public Long getId() { return id; }
    public void setId(Long id) { this.id = id; }
    /**
     * @hibernate.property column="name"
     * @return
     */
    public String getName() { return name; }
    public void setName(String name) { this.name = name;   }
    /**
     * @hibernate.property column="start_date"
     * @return
     */
    public Date getStartDate() { return startDate; }
    public void setStartDate(Date startDate) { this.startDate = startDate; }
    /**
     * @hibernate.property column="duration"
     * @return
     */
    public int getDuration() { return duration; }
    public void setDuration(int duration) { this.duration = duration; }
}


/////////////////////////////////////////////////////////////////////////





Simple Dao Delete

/////////////////////////////////////////////////////////////////////////
import java.util.*;
import org.hibernate.*;
import org.hibernate.criterion.*;
public class Main {
  
  
  public static void main(String[] args) {
    HibernateUtil.setup("create table EVENTS ( uid int, name VARCHAR, start_Date date, duration int);");
    
    // hibernate code start

        SimpleEventDao eventDao = new SimpleEventDao();
        Event event = new Event();
        event.setName("Create an Event");
        
        
        try {
            eventDao.create(event);            
            eventDao.delete(event);
        } catch (ObjectNotFoundException expected) {
            // expected
        }
        

        HibernateUtil.checkData("select uid, name from events");        
    // hibernate code end
  }
  
}

/////////////////////////////////////////////////////////////////////////
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.Query;
import org.apache.rumons.logging.Log;
import org.apache.rumons.logging.LogFactory;
import java.util.List;
public class SimpleEventDao {
    Log log = LogFactory.getLog(SimpleEventDao.class);
    private Session session;
    private Transaction tx;
    public SimpleEventDao() {
        HibernateFactory.buildIfNeeded();
    }
    /**
     * Insert a new Event into the database.
     * @param event
     */
    public void create(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.save(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }

    /**
     * Delete a detached Event from the database.
     * @param event
     */
    public void delete(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.delete(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }
    /**
     * Find an Event by its primary key.
     * @param id
     * @return
     */
    public Event find(Long id) throws DataAccessLayerException {
        Event event = null;
        try {
            startOperation();
            event = (Event) session.load(Event.class, id);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return event;
    }
    /**
     * Updates the state of a detached Event.
     *
     * @param event
     */
    public void update(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.update(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }
    /**
     * Finds all Events in the database.
     * @return
     */
    public List findAll() throws DataAccessLayerException{
        List events = null;
        try {
            startOperation();
            Query query = session.createQuery("from Event");
            events =  query.list();
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return events;
    }
    private void handleException(HibernateException e) throws DataAccessLayerException {
        HibernateFactory.rollback(tx);
        throw new DataAccessLayerException(e);
    }
    private void startOperation() throws HibernateException {
        session = HibernateFactory.openSession();
        tx = session.beginTransaction();
    }
}


/////////////////////////////////////////////////////////////////////////
/**
 * Represents Exceptions thrown by the Data Access Layer.
 */
public class DataAccessLayerException extends RuntimeException {
    public DataAccessLayerException() {
    }
    public DataAccessLayerException(String message) {
        super(message);
    }
    public DataAccessLayerException(Throwable cause) {
        super(cause);
    }
    public DataAccessLayerException(String message, Throwable cause) {
        super(message, cause);
    }
}

/////////////////////////////////////////////////////////////////////////
<?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="uid" type="long">
            <generator class="increment"/>
        </id>
        <property name="name" type="string"/>
        <property name="startDate" column="start_date" type="date"/>
        <property name="duration" type="integer"/>
    </class>
</hibernate-mapping>


/////////////////////////////////////////////////////////////////////////
import java.io.Serializable;
import java.util.Date;
import java.util.Set;
import java.util.LinkedHashSet;
public class Event implements Serializable {
    private Long id;
    private int duration;
    private String name;
    private Date startDate;
    public Event() {
    }
    public Event(String name) {
        this.name = name;
    }
    /**
     * @hibernate.id generator-class="native" column="uid"
     * @return
     */
    public Long getId() { return id; }
    public void setId(Long id) { this.id = id; }
    /**
     * @hibernate.property column="name"
     * @return
     */
    public String getName() { return name; }
    public void setName(String name) { this.name = name;   }
    /**
     * @hibernate.property column="start_date"
     * @return
     */
    public Date getStartDate() { return startDate; }
    public void setStartDate(Date startDate) { this.startDate = startDate; }
    /**
     * @hibernate.property column="duration"
     * @return
     */
    public int getDuration() { return duration; }
    public void setDuration(int duration) { this.duration = duration; }
}





Simple Dao Find All

/////////////////////////////////////////////////////////////////////////
import java.util.*;
import org.hibernate.*;
import org.hibernate.criterion.*;
public class Main {
  
  
  public static void main(String[] args) {
    HibernateUtil.setup("create table EVENTS ( uid int, name VARCHAR, start_Date date, duration int);");
    
    // hibernate code start

        SimpleEventDao eventDao = new SimpleEventDao();
        Event event1 = new Event();
        Event event2 = new Event();
        event1.setName("Events 1");
        event2.setName("Events 2");
        eventDao.create(event1);
        eventDao.create(event2);
        List eventList = eventDao.findAll();
        
        System.out.println();
        System.out.println();
        System.out.println();
        System.out.println();
        System.out.println(eventList.size());
        
        HibernateUtil.checkData("select uid, name from events");        
    // hibernate code end
  }
  
}

/////////////////////////////////////////////////////////////////////////
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.Query;
import org.apache.rumons.logging.Log;
import org.apache.rumons.logging.LogFactory;
import java.util.List;
public class SimpleEventDao {
    Log log = LogFactory.getLog(SimpleEventDao.class);
    private Session session;
    private Transaction tx;
    public SimpleEventDao() {
        HibernateFactory.buildIfNeeded();
    }
    /**
     * Insert a new Event into the database.
     * @param event
     */
    public void create(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.save(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }

    /**
     * Delete a detached Event from the database.
     * @param event
     */
    public void delete(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.delete(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }
    /**
     * Find an Event by its primary key.
     * @param id
     * @return
     */
    public Event find(Long id) throws DataAccessLayerException {
        Event event = null;
        try {
            startOperation();
            event = (Event) session.load(Event.class, id);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return event;
    }
    /**
     * Updates the state of a detached Event.
     *
     * @param event
     */
    public void update(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.update(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }
    /**
     * Finds all Events in the database.
     * @return
     */
    public List findAll() throws DataAccessLayerException{
        List events = null;
        try {
            startOperation();
            Query query = session.createQuery("from Event");
            events =  query.list();
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return events;
    }
    private void handleException(HibernateException e) throws DataAccessLayerException {
        HibernateFactory.rollback(tx);
        throw new DataAccessLayerException(e);
    }
    private void startOperation() throws HibernateException {
        session = HibernateFactory.openSession();
        tx = session.beginTransaction();
    }
}


/////////////////////////////////////////////////////////////////////////
/**
 * Represents Exceptions thrown by the Data Access Layer.
 */
public class DataAccessLayerException extends RuntimeException {
    public DataAccessLayerException() {
    }
    public DataAccessLayerException(String message) {
        super(message);
    }
    public DataAccessLayerException(Throwable cause) {
        super(cause);
    }
    public DataAccessLayerException(String message, Throwable cause) {
        super(message, cause);
    }
}

/////////////////////////////////////////////////////////////////////////
<?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="uid" type="long">
            <generator class="increment"/>
        </id>
        <property name="name" type="string"/>
        <property name="startDate" column="start_date" type="date"/>
        <property name="duration" type="integer"/>
    </class>
</hibernate-mapping>


/////////////////////////////////////////////////////////////////////////
import java.io.Serializable;
import java.util.Date;
import java.util.Set;
import java.util.LinkedHashSet;
public class Event implements Serializable {
    private Long id;
    private int duration;
    private String name;
    private Date startDate;
    public Event() {
    }
    public Event(String name) {
        this.name = name;
    }
    /**
     * @hibernate.id generator-class="native" column="uid"
     * @return
     */
    public Long getId() { return id; }
    public void setId(Long id) { this.id = id; }
    /**
     * @hibernate.property column="name"
     * @return
     */
    public String getName() { return name; }
    public void setName(String name) { this.name = name;   }
    /**
     * @hibernate.property column="start_date"
     * @return
     */
    public Date getStartDate() { return startDate; }
    public void setStartDate(Date startDate) { this.startDate = startDate; }
    /**
     * @hibernate.property column="duration"
     * @return
     */
    public int getDuration() { return duration; }
    public void setDuration(int duration) { this.duration = duration; }
}





Simple Dao Load

/////////////////////////////////////////////////////////////////////////
import java.util.*;
import org.hibernate.*;
import org.hibernate.criterion.*;
public class Main {
  
  
  public static void main(String[] args) {
    HibernateUtil.setup("create table EVENTS ( uid int, name VARCHAR, start_Date date, duration int);");
    
    // hibernate code start

        SimpleEventDao eventDao = new SimpleEventDao();
        Event event = new Event();
        event.setName("Create an Event");
        eventDao.create(event);
        
        Event foundEvent = eventDao.find(/*event.getId()*/1L);
        System.out.println(foundEvent.getName());
        
        HibernateUtil.checkData("select uid, name from events");        
    // hibernate code end
  }
  
}

/////////////////////////////////////////////////////////////////////////
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.Query;
import org.apache.rumons.logging.Log;
import org.apache.rumons.logging.LogFactory;
import java.util.List;
public class SimpleEventDao {
    Log log = LogFactory.getLog(SimpleEventDao.class);
    private Session session;
    private Transaction tx;
    public SimpleEventDao() {
        HibernateFactory.buildIfNeeded();
    }
    /**
     * Insert a new Event into the database.
     * @param event
     */
    public void create(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.save(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }

    /**
     * Delete a detached Event from the database.
     * @param event
     */
    public void delete(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.delete(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }
    /**
     * Find an Event by its primary key.
     * @param id
     * @return
     */
    public Event find(Long id) throws DataAccessLayerException {
        Event event = null;
        try {
            startOperation();
            event = (Event) session.load(Event.class, id);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return event;
    }
    /**
     * Updates the state of a detached Event.
     *
     * @param event
     */
    public void update(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.update(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }
    /**
     * Finds all Events in the database.
     * @return
     */
    public List findAll() throws DataAccessLayerException{
        List events = null;
        try {
            startOperation();
            Query query = session.createQuery("from Event");
            events =  query.list();
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return events;
    }
    private void handleException(HibernateException e) throws DataAccessLayerException {
        HibernateFactory.rollback(tx);
        throw new DataAccessLayerException(e);
    }
    private void startOperation() throws HibernateException {
        session = HibernateFactory.openSession();
        tx = session.beginTransaction();
    }
}


/////////////////////////////////////////////////////////////////////////
/**
 * Represents Exceptions thrown by the Data Access Layer.
 */
public class DataAccessLayerException extends RuntimeException {
    public DataAccessLayerException() {
    }
    public DataAccessLayerException(String message) {
        super(message);
    }
    public DataAccessLayerException(Throwable cause) {
        super(cause);
    }
    public DataAccessLayerException(String message, Throwable cause) {
        super(message, cause);
    }
}

/////////////////////////////////////////////////////////////////////////
<?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="uid" type="long">
            <generator class="increment"/>
        </id>
        <property name="name" type="string"/>
        <property name="startDate" column="start_date" type="date"/>
        <property name="duration" type="integer"/>
    </class>
</hibernate-mapping>


/////////////////////////////////////////////////////////////////////////
import java.io.Serializable;
import java.util.Date;
import java.util.Set;
import java.util.LinkedHashSet;
public class Event implements Serializable {
    private Long id;
    private int duration;
    private String name;
    private Date startDate;
    public Event() {
    }
    public Event(String name) {
        this.name = name;
    }
    /**
     * @hibernate.id generator-class="native" column="uid"
     * @return
     */
    public Long getId() { return id; }
    public void setId(Long id) { this.id = id; }
    /**
     * @hibernate.property column="name"
     * @return
     */
    public String getName() { return name; }
    public void setName(String name) { this.name = name;   }
    /**
     * @hibernate.property column="start_date"
     * @return
     */
    public Date getStartDate() { return startDate; }
    public void setStartDate(Date startDate) { this.startDate = startDate; }
    /**
     * @hibernate.property column="duration"
     * @return
     */
    public int getDuration() { return duration; }
    public void setDuration(int duration) { this.duration = duration; }
}





Simple Dao Update

/////////////////////////////////////////////////////////////////////////

import java.util.*;
import org.hibernate.*;
import org.hibernate.criterion.*;
public class Main {
  
  
  public static void main(String[] args) {
    HibernateUtil.setup("create table EVENTS ( uid int, name VARCHAR, start_Date date, duration int);");
    
    // hibernate code start

        SimpleEventDao eventDao = new SimpleEventDao();
        Event event1 = new Event();
        event1.setName("Events 1");
        eventDao.create(event1);
        event1.setName("new Name");
        
        eventDao.update(event1);
        
        System.out.println();
        System.out.println();
        System.out.println();
        System.out.println();
        
        
        HibernateUtil.checkData("select uid, name from events");        
    // hibernate code end
  }
  
}

/////////////////////////////////////////////////////////////////////////
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.Query;
import org.apache.rumons.logging.Log;
import org.apache.rumons.logging.LogFactory;
import java.util.List;
public class SimpleEventDao {
    Log log = LogFactory.getLog(SimpleEventDao.class);
    private Session session;
    private Transaction tx;
    public SimpleEventDao() {
        HibernateFactory.buildIfNeeded();
    }
    /**
     * Insert a new Event into the database.
     * @param event
     */
    public void create(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.save(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }

    /**
     * Delete a detached Event from the database.
     * @param event
     */
    public void delete(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.delete(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }
    /**
     * Find an Event by its primary key.
     * @param id
     * @return
     */
    public Event find(Long id) throws DataAccessLayerException {
        Event event = null;
        try {
            startOperation();
            event = (Event) session.load(Event.class, id);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return event;
    }
    /**
     * Updates the state of a detached Event.
     *
     * @param event
     */
    public void update(Event event) throws DataAccessLayerException {
        try {
            startOperation();
            session.update(event);
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
    }
    /**
     * Finds all Events in the database.
     * @return
     */
    public List findAll() throws DataAccessLayerException{
        List events = null;
        try {
            startOperation();
            Query query = session.createQuery("from Event");
            events =  query.list();
            tx.rumit();
        } catch (HibernateException e) {
            handleException(e);
        } finally {
            HibernateFactory.close(session);
        }
        return events;
    }
    private void handleException(HibernateException e) throws DataAccessLayerException {
        HibernateFactory.rollback(tx);
        throw new DataAccessLayerException(e);
    }
    private void startOperation() throws HibernateException {
        session = HibernateFactory.openSession();
        tx = session.beginTransaction();
    }
}


/////////////////////////////////////////////////////////////////////////
/**
 * Represents Exceptions thrown by the Data Access Layer.
 */
public class DataAccessLayerException extends RuntimeException {
    public DataAccessLayerException() {
    }
    public DataAccessLayerException(String message) {
        super(message);
    }
    public DataAccessLayerException(Throwable cause) {
        super(cause);
    }
    public DataAccessLayerException(String message, Throwable cause) {
        super(message, cause);
    }
}

/////////////////////////////////////////////////////////////////////////
<?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="uid" type="long">
            <generator class="increment"/>
        </id>
        <property name="name" type="string"/>
        <property name="startDate" column="start_date" type="date"/>
        <property name="duration" type="integer"/>
    </class>
</hibernate-mapping>


/////////////////////////////////////////////////////////////////////////
import java.io.Serializable;
import java.util.Date;
import java.util.Set;
import java.util.LinkedHashSet;
public class Event implements Serializable {
    private Long id;
    private int duration;
    private String name;
    private Date startDate;
    public Event() {
    }
    public Event(String name) {
        this.name = name;
    }
    /**
     * @hibernate.id generator-class="native" column="uid"
     * @return
     */
    public Long getId() { return id; }
    public void setId(Long id) { this.id = id; }
    /**
     * @hibernate.property column="name"
     * @return
     */
    public String getName() { return name; }
    public void setName(String name) { this.name = name;   }
    /**
     * @hibernate.property column="start_date"
     * @return
     */
    public Date getStartDate() { return startDate; }
    public void setStartDate(Date startDate) { this.startDate = startDate; }
    /**
     * @hibernate.property column="duration"
     * @return
     */
    public int getDuration() { return duration; }
    public void setDuration(int duration) { this.duration = duration; }
}