org.dspace.core

Interface GenericDAO<T>

Type Parameters:

T - type which is accessed by this DAO, for example Item.

All Known Subinterfaces:

BasicWorkflowItemDAO, BitstreamDAO, BitstreamFormatDAO, BundleDAO, ChecksumHistoryDAO, ChecksumResultDAO, ClaimedTaskDAO, CollectionDAO, CollectionRoleDAO, CommunityDAO, DOIDAO, DSpaceObjectDAO<T>, DSpaceObjectLegacySupportDAO<T>, EPersonDAO, Group2GroupCacheDAO, GroupDAO, HandleDAO, HarvestedCollectionDAO, HarvestedItemDAO, InProgressUserDAO, ItemDAO, MetadataFieldDAO, MetadataSchemaDAO, MetadataValueDAO, MostRecentChecksumDAO, PoolTaskDAO, RegistrationDataDAO, RequestItemDAO, ResourcePolicyDAO, SiteDAO, SubscriptionDAO, TaskListItemDAO, VersionDAO, VersionHistoryDAO, WebAppDAO, WorkflowItemRoleDAO, WorkspaceItemDAO, XmlWorkflowItemDAO

All Known Implementing Classes:

AbstractHibernateDAO, AbstractHibernateDSODAO, BasicWorkflowItemDAOImpl, BitstreamDAOImpl, BitstreamFormatDAOImpl, BundleDAOImpl, ChecksumHistoryDAOImpl, ChecksumResultDAOImpl, ClaimedTaskDAOImpl, CollectionDAOImpl, CollectionRoleDAOImpl, CommunityDAOImpl, DOIDAOImpl, EPersonDAOImpl, Group2GroupCacheDAOImpl, GroupDAOImpl, HandleDAOImpl, HarvestedCollectionDAOImpl, HarvestedItemDAOImpl, InProgressUserDAOImpl, ItemDAOImpl, MetadataFieldDAOImpl, MetadataSchemaDAOImpl, MetadataValueDAOImpl, MostRecentChecksumDAOImpl, PoolTaskDAOImpl, RegistrationDataDAOImpl, RequestItemDAOImpl, ResourcePolicyDAOImpl, SiteDAOImpl, SubscriptionDAOImpl, TaskListItemDAOImpl, VersionDAOImpl, VersionHistoryDAOImpl, WebAppDAOImpl, WorkflowItemRoleDAOImpl, WorkspaceItemDAOImpl, XmlWorkflowItemDAOImpl

public interface GenericDAO<T>

Generic Database Access Object interface class that should be implemented by all DAOs. It offers up a lot of general methods so these don't need to be declared again in each DAO. The default Hibernate implementation offers up a class that implements all these methods.

Author:

kevinvandevelde at atmire.com

Method Summary

Modifier and Type	Method and Description
T	create(Context context, T t) Create a new instance of this type in the database.
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, 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.
void	save(Context context, T t) Persist this instance in the database.

Method Detail

create

T create(Context context,
         T t)
  throws SQLException

Create a new instance of this type in the database.

Parameters:

context - current DSpace context.

t - type to be created.

Returns:

entity tracking the created instance.

Throws:

SQLException

save

void save(Context context,
          T t)
   throws SQLException

Persist this instance in the database.

Parameters:

context - current DSpace context.

t - type created here.

Throws:

SQLException - passed through.

delete

void delete(Context context,
            T t)
     throws SQLException

Remove an instance from the database.

Parameters:

context - current DSpace context.

t - type of the instance to be removed.

Throws:

SQLException - passed through.

findAll

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

Fetch all persisted instances of a given object type.

Parameters:

context -

clazz - the desired type.

Returns:

list of DAOs of the same type as clazz

Throws:

SQLException - if database error

findUnique

T findUnique(Context context,
             String query)
      throws SQLException

Execute a JPQL query returning a unique result.

Parameters:

context -

query - JPQL query string

Returns:

a DAO specified by the query string

Throws:

SQLException - if database error

findByID

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

Fetch the entity identified by its legacy database identifier.

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.

findByID

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

Fetch the entity identified by its UUID primary key.

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

findMany

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

Execute a JPQL 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