org.perfectjpattern.jee.integration.dao
Class JpaBaseDao<Id extends Serializable,Element>

java.lang.Object
  org.perfectjpattern.jee.integration.dao.JpaBaseDao<Id,Element>

All Implemented Interfaces:

IBaseDao<Id,Element>, IBaseReadOnlyDao<Id,Element>

Direct Known Subclasses:

AbstractJpaManagedBaseDao, HibernateGenericDao

public class JpaBaseDao<Id extends Serializable,Element>
extends Object
implements IBaseDao<Id,Element>

Abstract reusable JPA partial implementation of IGenericReadOnlyDao that provides automatic handling of EntityManager within a EJB container

Version:

$Revision: 1.0 $Date: Feb 11, 2009 10:17:46 AM $

Author:

Giovanni Azua

Constructor Summary

protected

JpaBaseDao(Class<Element> aPersistentClass, ISessionStrategy aSessionStrategy, ITransactionStrategy aTransactionStrategy) Constructs a HibernateGenericReadOnlyDao instance from the persistent class type, the ISessionStrategy that creates ISession instances and the ITransactionStrategy that creates ITransaction instances

Method Summary

boolean	contains(Element anElement) Returns true if the specified Element exists in the persistent storage, false otherwise.
int	count() Returns the total number of records.
Id	create(Element anElement) Returns the ID of the newly created Element.
boolean	delete(Element anElement) Returns true if the Element was deleted, false otherwise i.e.
void	deleteAll() Deletes all Element from the persistent storage.
List<Element>	findAll() Returns all Elements from the persistent storage.
Element	findById(Id anId) Returns the Element matching the given ID.
protected Class<Element>	getPersistentClass() Returns the persistentClass
ISession	getSession() Returns the ISession adapted from the implementation-specific
protected ISessionStrategy	getSessionStrategy() Returns the sessionStrategy
ITransaction	getTransaction() Returns the ITransaction adapted from the implementation-specific
protected ITransactionStrategy	getTransactionStrategy() Returns the transactionStrategy
protected void	setEntityManager(javax.persistence.EntityManager anEntityManager) Sets the EntityManager, called from a managed EJB that exposes IGenericReadOnlyDao or IGenericDao remotely.
boolean	update(Element anElement) Returns true if the Element was updated, false otherwise i.e.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

JpaBaseDao

protected JpaBaseDao(Class<Element> aPersistentClass,
                     ISessionStrategy aSessionStrategy,
                     ITransactionStrategy aTransactionStrategy)
              throws IllegalArgumentException

Constructs a HibernateGenericReadOnlyDao instance from the persistent class type, the ISessionStrategy that creates ISession instances and the ITransactionStrategy that creates ITransaction instances

Parameters:

aPersistentClass - The persistent Java Bean class

aSessionStrategy - Factory that creates Sessions

aTransactionStrategy - Factory that creates Transaction

Throws:

IllegalArgumentException

Method Detail

contains

public boolean contains(Element anElement)
                 throws DaoException,
                        IllegalArgumentException

Returns true if the specified Element exists in the persistent storage, false otherwise.

Specified by:

contains in interface IBaseReadOnlyDao<Id extends Serializable,Element>

Parameters:

anElement - Element to find in this persistent storage.

Returns:

true if Element exists in the persistent storage, false otherwise

Throws:

DaoException

IllegalArgumentException - 'anId' must not be null.

count

public int count()
          throws DaoException

Returns the total number of records. Provides a high-level reusable means to do a "SELECT * FROM ...". Noteworthy that every call to this function will trigger a new execution of a statement. Therefore if the count value is needed several times in the client code it is a good idea to cache it there.

Specified by:

count in interface IBaseReadOnlyDao<Id extends Serializable,Element>

Returns:

total number of records

Throws:

DaoException

findById

public Element findById(Id anId)
                 throws DaoException,
                        IllegalArgumentException

Returns the Element matching the given ID. Retrieves an Element from the persistent storage using as input its ID.

Specified by:

findById in interface IBaseReadOnlyDao<Id extends Serializable,Element>

Parameters:

anId - ID of the Element to retrieve.

Returns:

Element matching the given ID

Throws:

DaoException

IllegalArgumentException - 'anId' must not be null.

findAll

public List<Element> findAll()
                      throws DaoException

Returns all Elements from the persistent storage.

Specified by:

findAll in interface IBaseReadOnlyDao<Id extends Serializable,Element>

Returns:

all Elements from the persistent storage.

Throws:

DaoException

create

public Id create(Element anElement)
                               throws DaoException,
                                      IllegalArgumentException

Returns the ID of the newly created Element. Creates an Element in the persistent storage and returns its ID.

Specified by:

create in interface IBaseDao<Id extends Serializable,Element>

Parameters:

anElement - Element to create

Returns:

ID of the newly created Element

Throws:

DaoException

IllegalArgumentException - 'anElement' must not be null.

update

public boolean update(Element anElement)
               throws DaoException

Returns true if the Element was updated, false otherwise i.e. the Element was not found. Updates the given Element in the persistent storage.

Specified by:

update in interface IBaseDao<Id extends Serializable,Element>

Parameters:

anElement - Element to update

Returns:

true if the Element was updated, false otherwise.

Throws:

DaoException

delete

public boolean delete(Element anElement)
               throws DaoException

Returns true if the Element was deleted, false otherwise i.e. the Element was not found. Deletes the given Element from the persistent storage.

Specified by:

delete in interface IBaseDao<Id extends Serializable,Element>

Parameters:

anElement - Element to delete

Returns:

true if the Element was deleted, false otherwise.

Throws:

DaoException

deleteAll

public void deleteAll()
               throws DaoException

Deletes all Element from the persistent storage.

Specified by:

deleteAll in interface IBaseDao<Id extends Serializable,Element>

Throws:

DaoException

getTransaction

public ITransaction getTransaction()

Returns the ITransaction adapted from the implementation-specific

Specified by:

getTransaction in interface IBaseReadOnlyDao<Id extends Serializable,Element>

Returns:

ITransaction adapted from the implementation-specific

See Also:

IAdapter

getSession

public ISession getSession()

Returns the ISession adapted from the implementation-specific

Specified by:

getSession in interface IBaseReadOnlyDao<Id extends Serializable,Element>

Returns:

ISession adapted from the implementation-specific

See Also:

IAdapter

setEntityManager

protected void setEntityManager(javax.persistence.EntityManager anEntityManager)
                         throws IllegalArgumentException

Sets the EntityManager, called from a managed EJB that exposes IGenericReadOnlyDao or IGenericDao remotely.

Parameters:

anEntityManager - The EntityManager to set

Throws:

IllegalArgumentException - 'anEntityManager' must not be null

getPersistentClass

protected final Class<Element> getPersistentClass()

Returns the persistentClass

Returns:

the persistentClass

getSessionStrategy

protected final ISessionStrategy getSessionStrategy()

Returns the sessionStrategy

Returns:

the sessionStrategy

getTransactionStrategy

protected final ITransactionStrategy getTransactionStrategy()

Returns the transactionStrategy

Returns:

the transactionStrategy