io.oasp.module.jpa.dataaccess.base

Class AbstractGenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>

java.lang.Object

io.oasp.module.jpa.dataaccess.base.AbstractGenericDao<ID,E>

Type Parameters:

ID - is the generic type if the primary key.

E - is the generic type of the managed PersistenceEntity.

All Implemented Interfaces:

GenericDao<ID,E>

Direct Known Subclasses:

AbstractDao

public abstract class AbstractGenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>
extends Object
implements GenericDao<ID,E>

This is the abstract base-implementation of the GenericDao interface.

Author:

hohwille

Field Summary

Fields

Modifier and Type	Field and Description
private javax.persistence.EntityManager	entityManager
private static org.slf4j.Logger	LOG Logger instance.

Constructor Summary

Constructors

Constructor and Description
AbstractGenericDao() The constructor.

Method Summary

Methods

Modifier and Type	Method and Description
protected void	applyCriteria(net.sf.mmm.util.search.base.AbstractSearchCriteria criteria, com.mysema.query.jpa.impl.JPAQuery query) Applies the meta-data of the given search criteria to the given JPAQuery.
protected void	applyCriteria(net.sf.mmm.util.search.base.AbstractSearchCriteria criteria, javax.persistence.Query query) Applies the meta-data of the given search criteria to the given Query.
protected void	applyCriteria(SearchCriteriaTo criteria, com.mysema.query.jpa.impl.JPAQuery query) Applies the meta-data of the given search criteria to the given Query.
protected void	applyPagination(PaginationTo pagination, com.mysema.query.jpa.impl.JPAQuery query) Applies the pagination criteria to the given JPAQuery.
protected Long	calculateTotalBeforePagination(PaginationTo pagination, com.mysema.query.jpa.impl.JPAQuery query) Calculates the total number of entities the given query would return without pagination applied.
protected PaginationResultTo	createPaginationResult(PaginationTo pagination, com.mysema.query.jpa.impl.JPAQuery query) Creates a pagination result for the given pagination and query.
void	delete(E entity) Deletes a given entity.
void	delete(ID id) Deletes the entity with the given id.
void	delete(Iterable<? extends E> entities) Deletes the given entities.
boolean	exists(ID id) Returns whether an entity with the given id exists.
E	find(ID id) Retrieves an entity by its id.
protected List<E>	findAll()
List<E>	findAll(Iterable<ID> ids) Returns all instances of the type with the given IDs.
E	findOne(ID id) Retrieves an entity by its id.
protected PaginatedListTo<E>	findPaginated(SearchCriteriaTo criteria, com.mysema.query.jpa.impl.JPAQuery query, com.mysema.query.types.Expression<E> expr) Returns a paginated list of entities according to the supplied criteria.
protected PaginatedListTo<E>	findPaginated(SearchCriteriaTo criteria, javax.persistence.Query query, com.mysema.query.types.Expression<E> expr)
void	forceIncrementModificationCounter(E entity) Enforces to increment the modificationCounter e.g.
protected abstract Class<E>	getEntityClass()
protected javax.persistence.EntityManager	getEntityManager()
protected String	getEntityName()
protected boolean	isNew(E entity) Determines if the given PersistenceEntity is new.
E	save(E entity) Saves a given entity.
void	save(Iterable<? extends E> entities) Saves all given entities.
void	setEntityManager(javax.persistence.EntityManager entityManager)

Methods inherited from class java.lang.Object

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

Field Detail

LOG

private static final org.slf4j.Logger LOG

Logger instance.

entityManager

private javax.persistence.EntityManager entityManager

Constructor Detail

AbstractGenericDao

public AbstractGenericDao()

The constructor.

Method Detail

getEntityClass

protected abstract Class<E> getEntityClass()

Returns:

the Class reflecting the managed entity.

getEntityManager

protected javax.persistence.EntityManager getEntityManager()

Returns:

the EntityManager instance.

setEntityManager

public void setEntityManager(javax.persistence.EntityManager entityManager)

Parameters:

entityManager - the EntityManager to inject.

getEntityName

protected String getEntityName()

Returns:

the name of the managed entity.

save

public E save(E entity)

Description copied from interface: GenericDao

Saves a given entity. Use the returned instance for further operations as the save operation might have changed the entity instance completely.

Specified by:

save in interface GenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>

Parameters:

entity - the entity to save

Returns:

the saved entity

isNew

protected boolean isNew(E entity)

Determines if the given PersistenceEntity is new.

Parameters:

entity - is the PersistenceEntity to check.

Returns:

true if new, false otherwise (e.g. detached or managed.

save

public void save(Iterable<? extends E> entities)

Description copied from interface: GenericDao

Saves all given entities.

Specified by:

save in interface GenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>

Parameters:

entities - the entities to save

forceIncrementModificationCounter

public void forceIncrementModificationCounter(E entity)

Description copied from interface: GenericDao

Enforces to increment the modificationCounter e.g. to enforce that a parent object gets locked when its children are modified.
As an example we assume that we have the two optimistic locked entities Order and its contained OrderPosition. By default the users can modify an Order and each of its OrderPositions in parallel without getting a locking conflict. This can be desired. However, it can also be a demand that an Order gets approved and the user doing that is responsible for the total price as the sum of the prices of each OrderPosition. Now if another user is adding or changing an OrderPostion belonging to that Order in parallel the Order will get approved but the approved total price will differ from what the user has actually seen when he clicked on approve. To prevent this the use-case to modify an OrderPosition can use this method to trigger a locking on the associated Order. The implication is also that two users changing an OrderPosition associated with the same Order in parallel will get a conflict.

Specified by:

forceIncrementModificationCounter in interface GenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>

Parameters:

entity - that is getting checked.

findOne

public E findOne(ID id)

Description copied from interface: GenericDao

Retrieves an entity by its id.

Specified by:

findOne in interface GenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>

Parameters:

id - must not be null.

Returns:

the entity with the given id or null if none found

find

public E find(ID id)
                                                                throws net.sf.mmm.util.exception.api.ObjectNotFoundUserException

Description copied from interface: GenericDao

Retrieves an entity by its id.

Specified by:

find in interface GenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>

Parameters:

id - must not be null.

Returns:

the entity with the given id or null if none found

Throws:

net.sf.mmm.util.exception.api.ObjectNotFoundUserException - if the requested entity does not exists (use GenericDao.findOne(Object) to prevent).

exists

public boolean exists(ID id)

Description copied from interface: GenericDao

Returns whether an entity with the given id exists.

Specified by:

exists in interface GenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>

Parameters:

id - must not be null.

Returns:

true if an entity with the given id exists, false otherwise

findAll

protected List<E> findAll()

Returns:

an Iterable to find ALL managed entities from the persistent store. Not exposed to API by default as this might not make sense for all kind of entities.

findAll

public List<E> findAll(Iterable<ID> ids)

Description copied from interface: GenericDao

Returns all instances of the type with the given IDs.

Specified by:

findAll in interface GenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>

Parameters:

ids - are the IDs of all entities to retrieve e.g. as List.

Returns:

an Iterable with all entites for the given ids.

delete

public void delete(ID id)

Description copied from interface: GenericDao

Deletes the entity with the given id.

Specified by:

delete in interface GenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>

Parameters:

id - must not be null.

delete

public void delete(E entity)

Description copied from interface: GenericDao

Deletes a given entity.

Specified by:

delete in interface GenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>

Parameters:

entity - the entity to delete

delete

public void delete(Iterable<? extends E> entities)

Description copied from interface: GenericDao

Deletes the given entities.

Specified by:

delete in interface GenericDao<ID,E extends net.sf.mmm.util.entity.api.PersistenceEntity<ID>>

Parameters:

entities - the entities to delete

findPaginated

protected PaginatedListTo<E> findPaginated(SearchCriteriaTo criteria,
                               javax.persistence.Query query,
                               com.mysema.query.types.Expression<E> expr)

findPaginated

protected PaginatedListTo<E> findPaginated(SearchCriteriaTo criteria,
                               com.mysema.query.jpa.impl.JPAQuery query,
                               com.mysema.query.types.Expression<E> expr)

Returns a paginated list of entities according to the supplied criteria.

Applies limit and offset values to the supplied according to the supplied pagination information inside criteria.

If a total count of available entities is requested, will also execute a second query, without pagination parameters applied, to obtain said count.

Will install a query timeout if SearchCriteriaTo.getSearchTimeout() is not null.

Parameters:

criteria - contains information about the requested page.

query - is a query which is preconfigured with the desired conditions for the search.

expr - is used for the final mapping from the SQL result to the entities.

Returns:

a paginated list.

createPaginationResult

protected PaginationResultTo createPaginationResult(PaginationTo pagination,
                                        com.mysema.query.jpa.impl.JPAQuery query)

Creates a pagination result for the given pagination and query.

Needs to be called before pagination is applied to the query.

Parameters:

pagination - contains information about the requested page.

query - is a query preconfigured with the desired conditions for the search.

Returns:

information about the applied pagination.

calculateTotalBeforePagination

protected Long calculateTotalBeforePagination(PaginationTo pagination,
                                  com.mysema.query.jpa.impl.JPAQuery query)

Calculates the total number of entities the given query would return without pagination applied.

Needs to be called before pagination is applied to the query.

Parameters:

pagination - is the pagination information as requested by the client.

query - is the query for which to calculate the total.

Returns:

the total count, or null if PaginationTo.isTotal() is false.

applyPagination

protected void applyPagination(PaginationTo pagination,
                   com.mysema.query.jpa.impl.JPAQuery query)

Applies the pagination criteria to the given JPAQuery.

Parameters:

pagination - is the pagination criteria to apply.

query - is the JPAQuery to apply to.

applyCriteria

protected void applyCriteria(net.sf.mmm.util.search.base.AbstractSearchCriteria criteria,
                 com.mysema.query.jpa.impl.JPAQuery query)

Applies the meta-data of the given search criteria to the given JPAQuery.

Parameters:

criteria - is the search criteria to apply.

query - is the JPAQuery to apply to.

applyCriteria

protected void applyCriteria(net.sf.mmm.util.search.base.AbstractSearchCriteria criteria,
                 javax.persistence.Query query)

Applies the meta-data of the given search criteria to the given Query.

Parameters:

criteria - is the search criteria to apply.

query - is the Query to apply to.

applyCriteria

protected void applyCriteria(SearchCriteriaTo criteria,
                 com.mysema.query.jpa.impl.JPAQuery query)

Applies the meta-data of the given search criteria to the given Query.

Parameters:

criteria - is the search criteria to apply.

query - is the JPAQuery to apply to.