com.googlecode.genericdao.dao.hibernate

Class HibernateBaseDAO

java.lang.Object

com.googlecode.genericdao.dao.hibernate.HibernateBaseDAO

Direct Known Subclasses:

GeneralDAOImpl, GeneralDAOImpl, GenericDAOImpl, GenericDAOImpl

public class HibernateBaseDAO
extends Object

Base class for DAOs that uses Hibernate SessionFactory and HQL for searches. This is the heart of Hibernate Generic DAO.

Author:

dwolverton

Constructor Summary

Constructors

Constructor and Description
HibernateBaseDAO()

Method Summary

Methods

Modifier and Type	Method and Description
protected <T> List<T>	_all(Class<T> type) Get a list of all the objects of the specified class.
protected int	_count(Class<?> type) Returns the number of instances of this class in the datastore.
protected int	_count(Class<?> searchClass, ISearch search) Same as _count(ISearch) except that it uses the specified search class instead of getting it from the search object.
protected int	_count(ISearch search) Returns the total number of results that would be returned using the given ISearch if there were no paging or maxResult limits.
protected void	_deleteById(Class<?> type, Serializable... ids) Remove all the entities of the given type from the datastore that have one of these ids.
protected boolean	_deleteById(Class<?> type, Serializable id) Remove the entity of the specified class with the specified id from the datastore.
protected void	_deleteEntities(Object... entities) Remove the specified entities from the datastore.
protected boolean	_deleteEntity(Object entity) Remove the specified entity from the datastore.
protected boolean[]	_exists(Class<?> type, Serializable... ids)
protected boolean	_exists(Class<?> type, Serializable id)
protected boolean	_exists(Object entity)
protected void	_flush() Flushes changes in the hibernate cache to the datastore.
protected <T> T[]	_get(Class<T> type, Serializable... ids) Return the all the persistent instances of the given entity class with the given identifiers.
protected <T> T	_get(Class<T> type, Serializable id) Return the persistent instance of the given entity class with the given identifier, or null if there is no such persistent instance.
protected Filter	_getFilterFromExample(Object example)
protected Filter	_getFilterFromExample(Object example, ExampleOptions options)
protected <T> T[]	_load(Class<T> type, Serializable... ids) Return the persistent instance of the given entity class with the given identifier, assuming that the instance exists.
protected <T> T	_load(Class<T> type, Serializable id) Return the persistent instance of the given entity class with the given identifier, assuming that the instance exists.
protected void	_load(Object transientEntity, Serializable id) Read the persistent state associated with the given identifier into the given transient instance.
protected <T> T	_merge(T entity) Copy the state of the given object onto the persistent object with the same identifier.
protected void	_persist(Object... entities) Make a transient instance persistent and add it to the datastore.
protected void	_refresh(Object... entities) Refresh the content of the given entity from the current datastore state.
protected void	_save(Object... entities) Persist the given transient instances and add them to the datastore, first assigning a generated identifier.
protected Serializable	_save(Object entity) Persist the given transient instance and add it to the datastore, first assigning a generated identifier.
protected void	_saveOrUpdate(Object entity) Calls Hibernate's saveOrUpdate(), which behaves as follows:
protected boolean[]	_saveOrUpdateIsNew(Object... entities) Either save() or update() each entity, depending on whether or not an entity with the same id already exists in the datastore.
protected boolean	_saveOrUpdateIsNew(Object entity) If an entity already exists in the datastore with the same id, call _update and return false (not new).
protected List	_search(Class<?> searchClass, ISearch search) Same as _search(ISearch) except that it uses the specified search class instead of getting it from the search object.
protected List	_search(ISearch search) Search for objects based on the search parameters in the specified ISearch object.
protected SearchResult	_searchAndCount(Class<?> searchClass, ISearch search) Same as _searchAndCount(ISearch) except that it uses the specified search class instead of getting it from the search object.
protected SearchResult	_searchAndCount(ISearch search) Returns a SearchResult object that includes the list of results like search() and the total length like searchLength.
protected Object	_searchUnique(Class<?> searchClass, ISearch search) Same as _searchUnique(ISearch) except that it uses the specified search class instead of getting it from the search object.
protected Object	_searchUnique(ISearch search) Search for a single result using the given parameters.
protected boolean	_sessionContains(Object o) Returns true if the object is connected to the current hibernate session.
protected void	_update(Object... transientEntities) Update the persistent instance with the identifier of the given detached instance.
protected HibernateMetadataUtil	getMetadataUtil() Get the instance of HibernateMetadataUtil associated with the session factory
protected HibernateSearchProcessor	getSearchProcessor() Get the instance of EJBSearchProcessor associated with the session factory
protected org.hibernate.Session	getSession() Get the current Hibernate session
protected org.hibernate.SessionFactory	getSessionFactory()
void	setSessionFactory(org.hibernate.SessionFactory sessionFactory)

Methods inherited from class java.lang.Object

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

Constructor Detail

HibernateBaseDAO

public HibernateBaseDAO()

Method Detail

setSessionFactory

public void setSessionFactory(org.hibernate.SessionFactory sessionFactory)

getSessionFactory

protected org.hibernate.SessionFactory getSessionFactory()

getSession

protected org.hibernate.Session getSession()

Get the current Hibernate session

getMetadataUtil

protected HibernateMetadataUtil getMetadataUtil()

Get the instance of HibernateMetadataUtil associated with the session factory

getSearchProcessor

protected HibernateSearchProcessor getSearchProcessor()

Get the instance of EJBSearchProcessor associated with the session factory

_save

protected Serializable _save(Object entity)

Persist the given transient instance and add it to the datastore, first assigning a generated identifier. (Or using the current value of the identifier property if the assigned generator is used.) This operation cascades to associated instances if the association is mapped with cascade="save-update".

This is different from persist() in that it does guarantee that the object will be assigned an identifier immediately. With save() a call is made to the datastore immediately if the id is generated by the datastore so that the id can be determined. With persist this call may not occur until flush time.

Returns:

The id of the newly saved entity.

_save

protected void _save(Object... entities)

Persist the given transient instances and add them to the datastore, first assigning a generated identifier. (Or using the current value of the identifier property if the assigned generator is used.) This operation cascades to associated instances if the association is mapped with cascade="save-update".

_saveOrUpdate

protected void _saveOrUpdate(Object entity)

Calls Hibernate's saveOrUpdate(), which behaves as follows:

Either save() or update() based on the following rules

• if the object is already persistent in this session, do nothing
• if another object associated with the session has the same identifier, throw an exception
• if the object has no identifier property, save() it
• if the object's identifier has the value assigned to a newly instantiated object, save() it
• if the object is versioned (by a <version> or <timestamp>), and the version property value is the same value assigned to a newly instantiated object, save() it
• otherwise update() the object

_saveOrUpdateIsNew

protected boolean _saveOrUpdateIsNew(Object entity)

If an entity already exists in the datastore with the same id, call _update and return false (not new). If no such entity exists in the datastore, call _save() and return true (new)

Returns:

true if _save(); false if _update().

_saveOrUpdateIsNew

protected boolean[] _saveOrUpdateIsNew(Object... entities)

Either save() or update() each entity, depending on whether or not an entity with the same id already exists in the datastore.

Returns:

an boolean array corresponding to to the input list of entities. Each element is true if the corresponding entity was _save()d or false if it was _update()d.

_persist

protected void _persist(Object... entities)

Make a transient instance persistent and add it to the datastore. This operation cascades to associated instances if the association is mapped with cascade="persist". Throws an error if the entity already exists.

This is different from save() in that it does not guarantee that the object will be assigned an identifier immediately. With save() a call is made to the datastore immediately if the id is generated by the datastore so that the id can be determined. With persist this call may not occur until flush time.

_deleteById

protected boolean _deleteById(Class<?> type,
                  Serializable id)

Remove the entity of the specified class with the specified id from the datastore.

Returns:

true if the object is found in the datastore and deleted, false if the item is not found.

_deleteById

protected void _deleteById(Class<?> type,
               Serializable... ids)

Remove all the entities of the given type from the datastore that have one of these ids.

_deleteEntity

protected boolean _deleteEntity(Object entity)

Remove the specified entity from the datastore.

Returns:

true if the object is found in the datastore and removed, false if the item is not found.

_deleteEntities

protected void _deleteEntities(Object... entities)

Remove the specified entities from the datastore.

_get

protected <T> T _get(Class<T> type,
         Serializable id)

Return the persistent instance of the given entity class with the given identifier, or null if there is no such persistent instance. get() always hits the database immediately.

_get

protected <T> T[] _get(Class<T> type,
           Serializable... ids)

Return the all the persistent instances of the given entity class with the given identifiers. An array of entities is returned that matches the same order of the ids listed in the call. For each entity that is not found in the datastore, a null will be inserted in its place in the return array.

get() always hits the database immediately.

_load

protected <T> T _load(Class<T> type,
          Serializable id)

Return the persistent instance of the given entity class with the given identifier, assuming that the instance exists. Throw an unrecoverable exception if there is no matching database row.

If the class is mapped with a proxy, load() just returns an uninitialized proxy and does not actually hit the database until you invoke a method of the proxy. This behaviour is very useful if you wish to create an association to an object without actually loading it from the database. It also allows multiple instances to be loaded as a batch if batch-size is defined for the class mapping.

_load

protected <T> T[] _load(Class<T> type,
            Serializable... ids)

Return the persistent instance of the given entity class with the given identifier, assuming that the instance exists. Throw an unrecoverable exception if there is no matching database row. An array of entities is returned that matches the same order of the ids listed in the call. For each entity that is not found in the datastore, a null will be inserted in its place in the return array.

See Also:

_load(Class, Serializable)

_load

protected void _load(Object transientEntity,
         Serializable id)

Read the persistent state associated with the given identifier into the given transient instance. Throw an unrecoverable exception if there is no matching database row.

_all

protected <T> List<T> _all(Class<T> type)

Get a list of all the objects of the specified class.

_update

protected void _update(Object... transientEntities)

Update the persistent instance with the identifier of the given detached instance. If there is a persistent instance with the same identifier, an exception is thrown. This operation cascades to associated instances if the association is mapped with cascade="save-update".

The difference between update() and merge() is significant: update() will make the given object persistent and throw and error if another object with the same ID is already persistent in the Session. merge() doesn't care if another object is already persistent, but it also doesn't make the given object persistent; it just copies over the values to the datastore.

_merge

protected <T> T _merge(T entity)

Copy the state of the given object onto the persistent object with the same identifier. If there is no persistent instance currently associated with the session, it will be loaded. Return the persistent instance. If the given instance is unsaved, save a copy of and return it as a newly persistent instance. The given instance does not become associated with the session. This operation cascades to associated instances if the association is mapped with cascade="merge".

The difference between update() and merge() is significant: update() will make the given object persistent and throw and error if another object with the same ID is already persistent in the Session. merge() doesn't care if another object is already persistent, but it also doesn't make the given object persistent; it just copies over the values to the datastore.

_search

protected List _search(ISearch search)

Search for objects based on the search parameters in the specified ISearch object.

See Also:

ISearch

_search

protected List _search(Class<?> searchClass,
           ISearch search)

Same as _search(ISearch) except that it uses the specified search class instead of getting it from the search object. Also, if the search object has a different search class than what is specified, an exception is thrown.

_count

protected int _count(ISearch search)

Returns the total number of results that would be returned using the given ISearch if there were no paging or maxResult limits.

See Also:

ISearch

_count

protected int _count(Class<?> searchClass,
         ISearch search)

Same as _count(ISearch) except that it uses the specified search class instead of getting it from the search object. Also, if the search object has a different search class than what is specified, an exception is thrown.

_count

protected int _count(Class<?> type)

Returns the number of instances of this class in the datastore.

_searchAndCount

protected SearchResult _searchAndCount(ISearch search)

Returns a SearchResult object that includes the list of results like search() and the total length like searchLength.

See Also:

ISearch

_searchAndCount

protected SearchResult _searchAndCount(Class<?> searchClass,
                           ISearch search)

Same as _searchAndCount(ISearch) except that it uses the specified search class instead of getting it from the search object. Also, if the search object has a different search class than what is specified, an exception is thrown.

_searchUnique

protected Object _searchUnique(ISearch search)
                        throws org.hibernate.NonUniqueResultException

Search for a single result using the given parameters.

Throws:

org.hibernate.NonUniqueResultException

_searchUnique

protected Object _searchUnique(Class<?> searchClass,
                   ISearch search)

Same as _searchUnique(ISearch) except that it uses the specified search class instead of getting it from the search object. Also, if the search object has a different search class than what is specified, an exception is thrown.

_sessionContains

protected boolean _sessionContains(Object o)

Returns true if the object is connected to the current hibernate session.

_flush

protected void _flush()

Flushes changes in the hibernate cache to the datastore.

_refresh

protected void _refresh(Object... entities)

Refresh the content of the given entity from the current datastore state.

_exists

protected boolean _exists(Object entity)

_exists

protected boolean _exists(Class<?> type,
              Serializable id)

_exists

protected boolean[] _exists(Class<?> type,
                Serializable... ids)

_getFilterFromExample

protected Filter _getFilterFromExample(Object example)

_getFilterFromExample

protected Filter _getFilterFromExample(Object example,
                           ExampleOptions options)