org.dspace.core

Class AbstractHibernateDAO<T>

java.lang.Object

org.dspace.core.AbstractHibernateDAO<T>

Type Parameters:

T - class type

All Implemented Interfaces:

GenericDAO<T>

Direct Known Subclasses:

AbstractHibernateDSODAO, BasicWorkflowItemDAOImpl, BitstreamFormatDAOImpl, ChecksumHistoryDAOImpl, ChecksumResultDAOImpl, ClaimedTaskDAOImpl, CollectionRoleDAOImpl, DOIDAOImpl, Group2GroupCacheDAOImpl, HandleDAOImpl, HarvestedCollectionDAOImpl, HarvestedItemDAOImpl, InProgressUserDAOImpl, MetadataFieldDAOImpl, MetadataSchemaDAOImpl, MetadataValueDAOImpl, MostRecentChecksumDAOImpl, PoolTaskDAOImpl, RegistrationDataDAOImpl, RequestItemDAOImpl, ResourcePolicyDAOImpl, SiteDAOImpl, SubscriptionDAOImpl, TaskListItemDAOImpl, VersionDAOImpl, VersionHistoryDAOImpl, WebAppDAOImpl, WorkflowItemRoleDAOImpl, WorkspaceItemDAOImpl, XmlWorkflowItemDAOImpl

public abstract class AbstractHibernateDAO<T>
extends Object
implements GenericDAO<T>

Hibernate implementation for generic DAO interface. Also includes additional Hibernate calls that are commonly used. Each DAO should extend this class to prevent code duplication.

Author:

kevinvandevelde at atmire.com

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractHibernateDAO()

Method Summary

Modifier and Type	Method and Description
int	count(org.hibernate.Criteria criteria) How many rows match these criteria? The same value as countLong(Criteria), coerced to int.
int	count(org.hibernate.Query query) How many rows match this query?
long	countLong(org.hibernate.Criteria criteria) How many rows match these criteria?
T	create(Context context, T t) Create a new instance of this type in the database.
org.hibernate.Criteria	createCriteria(Context context, Class<T> persistentClass) Create criteria matching an entity type or a supertype thereof.
org.hibernate.Criteria	createCriteria(Context context, Class<T> persistentClass, String alias) Create criteria matching an entity type or a supertype thereof.
org.hibernate.Query	createQuery(Context context, String query) Create a parsed query from a query expression.
void	delete(Context context, T t) Remove an instance from the database.
List<T>	findAll(Context context, Class<T> clazz) Fetch all persisted instances of a given object type.
T	findByID(Context context, Class clazz, int id) Fetch the entity identified by its legacy database identifier.
T	findByID(Context context, Class clazz, UUID id) Fetch the entity identified by its UUID primary key.
List<T>	findMany(Context context, org.hibernate.Query query) Execute a JPA Criteria query and return a collection of results.
List<T>	findMany(Context context, String query) Execute a JPQL query and return a collection of results.
T	findUnique(Context context, String query) Execute a JPQL query returning a unique result.
protected org.hibernate.Session	getHibernateSession(Context context) The Session used to manipulate entities of this type.
Iterator<T>	iterate(org.hibernate.Query query) Get an iterator over a stream of query results.
List<T>	list(org.hibernate.Criteria criteria) Get the entities matched by the given Criteria.
List<T>	list(org.hibernate.Query query) Get the entities matching a given parsed query.
void	save(Context context, T t) Persist this instance in the database.
T	singleResult(org.hibernate.Criteria criteria) Retrieve a single result selected by criteria.
T	singleResult(org.hibernate.Query query) Retrieve a single result matching a query.
T	uniqueResult(org.hibernate.Criteria criteria) Retrieve a unique result selected by criteria.
T	uniqueResult(org.hibernate.Query query) Retrieve a unique result selected by a query.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractHibernateDAO

protected AbstractHibernateDAO()

Method Detail

create

public T create(Context context,
                T t)
         throws SQLException

Description copied from interface: GenericDAO

Create a new instance of this type in the database.

Specified by:

create in interface GenericDAO<T>

Parameters:

context - current DSpace context.

t - type to be created.

Returns:

entity tracking the created instance.

Throws:

SQLException

save

public void save(Context context,
                 T t)
          throws SQLException

Description copied from interface: GenericDAO

Persist this instance in the database.

Specified by:

save in interface GenericDAO<T>

Parameters:

context - current DSpace context.

t - type created here.

Throws:

SQLException - passed through.

getHibernateSession

protected org.hibernate.Session getHibernateSession(Context context)
                                             throws SQLException

The Session used to manipulate entities of this type.

Parameters:

context - current DSpace context.

Returns:

the current Session.

Throws:

SQLException

delete

public void delete(Context context,
                   T t)
            throws SQLException

Description copied from interface: GenericDAO

Remove an instance from the database.

Specified by:

delete in interface GenericDAO<T>

Parameters:

context - current DSpace context.

t - type of the instance to be removed.

Throws:

SQLException - passed through.

findAll

public List<T> findAll(Context context,
                       Class<T> clazz)
                throws SQLException

Description copied from interface: GenericDAO

Fetch all persisted instances of a given object type.

Specified by:

findAll in interface GenericDAO<T>

clazz - the desired type.

Returns:

list of DAOs of the same type as clazz

Throws:

SQLException - if database error

findUnique

public T findUnique(Context context,
                    String query)
             throws SQLException

Description copied from interface: GenericDAO

Execute a JPQL query returning a unique result.

Specified by:

findUnique in interface GenericDAO<T>

query - JPQL query string

Returns:

a DAO specified by the query string

Throws:

SQLException - if database error

findByID

public T findByID(Context context,
                  Class clazz,
                  UUID id)
           throws SQLException

Description copied from interface: GenericDAO

Fetch the entity identified by its UUID primary key.

Specified by:

findByID in interface GenericDAO<T>

Parameters:

context - current DSpace context.

clazz - class of entity to be found.

id - primary key of the database record.

Returns:

the found entity.

Throws:

SQLException

findByID

public T findByID(Context context,
                  Class clazz,
                  int id)
           throws SQLException

Description copied from interface: GenericDAO

Fetch the entity identified by its legacy database identifier.

Specified by:

findByID in interface GenericDAO<T>

Parameters:

context - current DSpace context.

clazz - class of entity to be found.

id - legacy database record ID.

Returns:

the found entity.

Throws:

SQLException - passed through.

findMany

public List<T> findMany(Context context,
                        String query)
                 throws SQLException

Description copied from interface: GenericDAO

Execute a JPQL query and return a collection of results.

Specified by:

findMany in interface GenericDAO<T>

query - JPQL query string

Returns:

list of DAOs specified by the query string

Throws:

SQLException - if database error

findMany

public List<T> findMany(Context context,
                        org.hibernate.Query query)
                 throws SQLException

Execute a JPA Criteria query and return a collection of results.

Parameters:

context -

query - JPQL query string

Returns:

list of DAOs specified by the query string

Throws:

SQLException - if database error

createCriteria

public org.hibernate.Criteria createCriteria(Context context,
                                             Class<T> persistentClass)
                                      throws SQLException

Create criteria matching an entity type or a supertype thereof. Use when building a criteria query.

Parameters:

context - current DSpace context.

persistentClass - specifies the type to be matched by the criteria.

Returns:

criteria concerning the type to be found.

Throws:

SQLException - passed through.

createCriteria

public org.hibernate.Criteria createCriteria(Context context,
                                             Class<T> persistentClass,
                                             String alias)
                                      throws SQLException

Create criteria matching an entity type or a supertype thereof. Use when building a criteria query.

Parameters:

context - current DSpace context.

persistentClass - specifies the type to be matched by the criteria.

alias - alias for the type.

Returns:

criteria concerning the type to be found.

Throws:

SQLException - passed through.

createQuery

public org.hibernate.Query createQuery(Context context,
                                       String query)
                                throws SQLException

Create a parsed query from a query expression.

Parameters:

context - current DSpace context.

query - textual form of the query.

Returns:

parsed form of the query.

Throws:

SQLException

list

public List<T> list(org.hibernate.Criteria criteria)

Get the entities matched by the given Criteria. Use this if you need all results together.

Parameters:

criteria - description of desired entities.

Returns:

the entities matched.

list

public List<T> list(org.hibernate.Query query)

Get the entities matching a given parsed query. Use this if you need all results together.

Parameters:

query - the query to be executed.

Returns:

entities matching the query.

uniqueResult

public T uniqueResult(org.hibernate.Criteria criteria)

Retrieve a unique result selected by criteria. If multiple results CAN be retrieved an exception will be thrown, so only use when the criteria state uniqueness in the database.

Parameters:

criteria - description of the desired entity.

Returns:

a DAO specified by the criteria

uniqueResult

public T uniqueResult(org.hibernate.Query query)

Retrieve a unique result selected by a query. If multiple results CAN be retrieved then an exception will be thrown, so only use when the query states uniqueness in the database.

Parameters:

query - description of the desired entity.

Returns:

the found entity.

singleResult

public T singleResult(org.hibernate.Criteria criteria)

Retrieve a single result selected by criteria. Best used if you expect a single result, but this isn't enforced on the database.

Parameters:

criteria - description of the desired entities.

Returns:

a DAO specified by the criteria

singleResult

public T singleResult(org.hibernate.Query query)

Retrieve a single result matching a query. Best used if you expect a single result, but this isn't enforced on the database.

Parameters:

query - description of desired entities.

Returns:

matched entities.

iterate

public Iterator<T> iterate(org.hibernate.Query query)

Get an iterator over a stream of query results. Use this when consuming results one at a time.

Parameters:

query - description of desired entities.

Returns:

iterator over the results of the query.

count

public int count(org.hibernate.Criteria criteria)

How many rows match these criteria? The same value as countLong(Criteria), coerced to int.

Parameters:

criteria - description of the rows.

Returns:

count of matching rows.

count

public int count(org.hibernate.Query query)

How many rows match this query?

Parameters:

query - description of the rows.

Returns:

count of matching rows.

countLong

public long countLong(org.hibernate.Criteria criteria)

How many rows match these criteria?

Parameters:

criteria - description of the rows.

Returns:

count of matching rows.