com.googlecode.genericdao.dao.hibernate.HibernateBaseDAO Maven / Gradle / Ivy
/* Copyright 2013 David Wolverton
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.googlecode.genericdao.dao.hibernate;
import java.io.Serializable;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.hibernate.Criteria;
import org.hibernate.NonUniqueResultException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.criterion.Restrictions;
import com.googlecode.genericdao.search.ExampleOptions;
import com.googlecode.genericdao.search.Filter;
import com.googlecode.genericdao.search.ISearch;
import com.googlecode.genericdao.search.SearchResult;
import com.googlecode.genericdao.search.hibernate.HibernateMetadataUtil;
import com.googlecode.genericdao.search.hibernate.HibernateSearchProcessor;
/**
* Base class for DAOs that uses Hibernate SessionFactory and HQL for searches.
* This is the heart of Hibernate Generic DAO.
*
* @author dwolverton
*
*/
@SuppressWarnings("unchecked")
public class HibernateBaseDAO {
private HibernateSearchProcessor searchProcessor;
private SessionFactory sessionFactory;
private HibernateMetadataUtil metadataUtil;
public void setSessionFactory(SessionFactory sessionFactory) {
this.sessionFactory = sessionFactory;
searchProcessor = HibernateSearchProcessor.getInstanceForSessionFactory(sessionFactory);
metadataUtil = HibernateMetadataUtil.getInstanceForSessionFactory(sessionFactory);
}
protected SessionFactory getSessionFactory() {
return sessionFactory;
}
/**
* Get the current Hibernate session
*/
protected Session getSession() {
return sessionFactory.getCurrentSession();
}
/**
* Get the instance of HibernateMetadataUtil associated with the session
* factory
*/
protected HibernateMetadataUtil getMetadataUtil() {
return metadataUtil;
}
/**
* Get the instance of EJBSearchProcessor associated with the session
* factory
*/
protected HibernateSearchProcessor getSearchProcessor() {
return searchProcessor;
}
/**
*
* 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.
*
* @return The id of the newly saved entity.
*/
protected Serializable _save(Object entity) {
return getSession().save(entity);
}
/**
* 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".
*/
protected void _save(Object... entities) {
for (Object entity : entities) {
_save(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
*
*/
protected void _saveOrUpdate(Object entity) {
getSession().saveOrUpdate(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)
*
* @return true if _save(); false if _update().
*/
protected boolean _saveOrUpdateIsNew(Object entity) {
if (entity == null)
throw new IllegalArgumentException("attempt to saveOrUpdate with null entity");
Serializable id = getMetadataUtil().getId(entity);
if (getSession().contains(entity))
return false;
if (id == null || (new Long(0)).equals(id) || !_exists(entity)) {
_save(entity);
return true;
} else {
_update(entity);
return false;
}
}
/**
* Either save() or update() each entity,
* depending on whether or not an entity with the same id already exists in
* the datastore.
*
* @return 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.
*/
protected boolean[] _saveOrUpdateIsNew(Object... entities) {
Boolean[] exists = new Boolean[entities.length];
// if an entity is contained in the session, it exists; if it has no id,
// it does not exist
for (int i = 0; i < entities.length; i++) {
if (entities[i] == null) {
throw new IllegalArgumentException("attempt to saveOrUpdate with null entity");
}
if (getSession().contains(entities[i])) {
exists[i] = true;
} else {
Serializable id = getMetadataUtil().getId(entities[i]);
if (id == null || (new Long(0)).equals(id)) {
exists[i] = false;
}
}
}
// if it has an id and is not contained in the session, it may exist
Map, List> mayExist = new HashMap, List>();
for (int i = 0; i < entities.length; i++) {
if (exists[i] == null) {
Class entityClass = metadataUtil.getUnproxiedClass(entities[i]); //Get the real entity class
List l = mayExist.get(entityClass);
if (l == null) {
l = new ArrayList();
mayExist.put(entityClass, l);
}
l.add(i);
}
}
// for each type of entity, do a batch call to the datastore to see
// which of the entities of that class exist
for (Map.Entry, List> entry : mayExist.entrySet()) {
Serializable[] ids = new Serializable[entry.getValue().size()];
for (int i = 0; i < ids.length; i++) {
ids[i] = getMetadataUtil().getId(entities[entry.getValue().get(i)]);
}
boolean exists2[] = _exists(entry.getKey(), ids);
for (int i = 0; i < ids.length; i++) {
exists[entry.getValue().get(i)] = exists2[i];
}
}
boolean[] isNew = new boolean[entities.length];
// now that we know which ones exist, save or update each.
for (int i = 0; i < entities.length; i++) {
if (entities[i] != null) {
if (exists[i]) {
_update(entities[i]);
isNew[i] = false;
} else {
_save(entities[i]);
isNew[i] = true;
}
}
}
return isNew;
}
/**
*
* 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.
*/
protected void _persist(Object... entities) {
for (Object entity : entities) {
getSession().persist(entity);
}
}
/**
* Remove the entity of the specified class with the specified id from the
* datastore.
*
* @return true if the object is found in the datastore and
* deleted, false if the item is not found.
*/
protected boolean _deleteById(Class type, Serializable id) {
if (id != null) {
type = metadataUtil.getUnproxiedClass(type); //Get the real entity class
Object entity = getSession().get(type, id);
if (entity != null) {
getSession().delete(entity);
return true;
}
}
return false;
}
/**
* Remove all the entities of the given type from the datastore that have
* one of these ids.
*/
protected void _deleteById(Class type, Serializable... ids) {
type = metadataUtil.getUnproxiedClass(type); //Get the real entity class
Criteria c = getSession().createCriteria(type);
c.add(Restrictions.in("id", ids));
for (Object entity : c.list()) {
getSession().delete(entity);
}
}
/**
* Remove the specified entity from the datastore.
*
* @return true if the object is found in the datastore and
* removed, false if the item is not found.
*/
protected boolean _deleteEntity(Object entity) {
if (entity != null) {
Serializable id = getMetadataUtil().getId(entity);
if (id != null) {
entity = getSession().get(metadataUtil.getUnproxiedClass(entity), id);
if (entity != null) {
getSession().delete(entity);
return true;
}
}
}
return false;
}
/**
* Remove the specified entities from the datastore.
*/
protected void _deleteEntities(Object... entities) {
for (Object entity : entities) {
if (entity != null)
getSession().delete(entity);
}
}
/**
* 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.
*/
protected T _get(Class type, Serializable id) {
type = metadataUtil.getUnproxiedClass(type); //Get the real entity class
return (T) getSession().get(type, id);
}
/**
*
* 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.
*/
protected T[] _get(Class type, Serializable... ids) {
type = metadataUtil.getUnproxiedClass(type); //Get the real entity class
Criteria c = getSession().createCriteria(type);
c.add(Restrictions.in("id", ids));
Object[] retVal = (Object[]) Array.newInstance(type, ids.length);
for (Object entity : c.list()) {
Serializable id = getMetadataUtil().getId(entity);
for (int i = 0; i < ids.length; i++) {
if (id.equals(ids[i])) {
retVal[i] = entity;
break;
}
}
}
return (T[]) retVal;
}
/**
*
* 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.
*/
protected T _load(Class type, Serializable id) {
type = metadataUtil.getUnproxiedClass(type); //Get the real entity class
return (T) getSession().load(type, 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. 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 #_load(Class, Serializable)
*/
protected T[] _load(Class type, Serializable... ids) {
type = metadataUtil.getUnproxiedClass(type); //Get the real entity class
Object[] retVal = (Object[]) Array.newInstance(type, ids.length);
for (int i = 0; i < ids.length; i++) {
if (ids[i] != null)
retVal[i] = _load(type, ids[i]);
}
return (T[]) retVal;
}
/**
* 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.
*/
protected void _load(Object transientEntity, Serializable id) {
getSession().load(transientEntity, id);
}
/**
* Get a list of all the objects of the specified class.
*/
protected List _all(Class type) {
type = metadataUtil.getUnproxiedClass(type); //Get the real entity class
return getSession().createCriteria(type).setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY).list();
}
/**
*
* 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.
*/
protected void _update(Object... transientEntities) {
for (Object entity : transientEntities) {
getSession().update(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.
*/
protected T _merge(T entity) {
return (T) getSession().merge(entity);
}
/**
* Search for objects based on the search parameters in the specified
* ISearch object.
*
* @see ISearch
*/
protected List _search(ISearch search) {
if (search == null)
throw new NullPointerException("Search is null.");
if (search.getSearchClass() == null)
throw new NullPointerException("Search class is null.");
return getSearchProcessor().search(getSession(), 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.
*/
protected List _search(Class searchClass, ISearch search) {
if (search == null)
throw new NullPointerException("Search is null.");
if (searchClass == null)
throw new NullPointerException("Search class is null.");
if (search.getSearchClass() != null && !search.getSearchClass().equals(searchClass))
throw new IllegalArgumentException("Search class does not match expected type: " + searchClass.getName());
return getSearchProcessor().search(getSession(), searchClass, search);
}
/**
* Returns the total number of results that would be returned using the
* given ISearch if there were no paging or maxResult limits.
*
* @see ISearch
*/
protected int _count(ISearch search) {
if (search == null)
throw new NullPointerException("Search is null.");
if (search.getSearchClass() == null)
throw new NullPointerException("Search class is null.");
return getSearchProcessor().count(getSession(), 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.
*/
protected int _count(Class searchClass, ISearch search) {
if (search == null)
throw new NullPointerException("Search is null.");
if (searchClass == null)
throw new NullPointerException("Search class is null.");
if (search.getSearchClass() != null && !search.getSearchClass().equals(searchClass))
throw new IllegalArgumentException("Search class does not match expected type: " + searchClass.getName());
return getSearchProcessor().count(getSession(), searchClass, search);
}
/**
* Returns the number of instances of this class in the datastore.
*/
protected int _count(Class type) {
List counts = getSession().createQuery("select count(_it_) from " + getMetadataUtil().get(type).getEntityName() + " _it_").list();
int sum = 0;
for (Object count : counts) {
sum += ((Long) count).intValue();
}
return sum;
}
/**
* Returns a SearchResult object that includes the list of
* results like search() and the total length like
* searchLength.
*
* @see ISearch
*/
protected SearchResult _searchAndCount(ISearch search) {
if (search == null)
throw new NullPointerException("Search is null.");
if (search.getSearchClass() == null)
throw new NullPointerException("Search class is null.");
return getSearchProcessor().searchAndCount(getSession(), 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.
*/
protected SearchResult _searchAndCount(Class searchClass, ISearch search) {
if (search == null)
throw new NullPointerException("Search is null.");
if (searchClass == null)
throw new NullPointerException("Search class is null.");
if (search.getSearchClass() != null && !search.getSearchClass().equals(searchClass))
throw new IllegalArgumentException("Search class does not match expected type: " + searchClass.getName());
return getSearchProcessor().searchAndCount(getSession(), searchClass, search);
}
/**
* Search for a single result using the given parameters.
*/
protected Object _searchUnique(ISearch search) throws NonUniqueResultException {
if (search == null)
throw new NullPointerException("Search is null.");
if (search.getSearchClass() == null)
throw new NullPointerException("Search class is null.");
return getSearchProcessor().searchUnique(getSession(), 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.
*/
protected Object _searchUnique(Class searchClass, ISearch search) {
if (search == null)
throw new NullPointerException("Search is null.");
if (searchClass == null)
throw new NullPointerException("Search class is null.");
if (search.getSearchClass() != null && !search.getSearchClass().equals(searchClass))
throw new IllegalArgumentException("Search class does not match expected type: " + searchClass.getName());
return getSearchProcessor().searchUnique(getSession(), searchClass, search);
}
/**
* Returns true if the object is connected to the current hibernate session.
*/
protected boolean _sessionContains(Object o) {
return getSession().contains(o);
}
/**
* Flushes changes in the hibernate cache to the datastore.
*/
protected void _flush() {
getSession().flush();
}
/**
* Refresh the content of the given entity from the current datastore state.
*/
protected void _refresh(Object... entities) {
for (Object entity : entities)
getSession().refresh(entity);
}
protected boolean _exists(Object entity) {
if (getSession().contains(entity))
return true;
return _exists(entity.getClass(), getMetadataUtil().getId(entity));
}
protected boolean _exists(Class type, Serializable id) {
if (type == null)
throw new NullPointerException("Type is null.");
if (id == null)
return false;
type = metadataUtil.getUnproxiedClass(type); //Get the real entity class
Query query = getSession().createQuery("select id from " + getMetadataUtil().get(type).getEntityName() + " where id = :id");
query.setParameter("id", id);
return query.list().size() == 1;
}
protected boolean[] _exists(Class type, Serializable... ids) {
if (type == null)
throw new NullPointerException("Type is null.");
type = metadataUtil.getUnproxiedClass(type); //Get the real entity class
boolean[] ret = new boolean[ids.length];
// we can't use "id in (:ids)" because some databases do not support
// this for compound ids.
StringBuilder sb = new StringBuilder("select id from " + getMetadataUtil().get(type).getEntityName() + " where");
boolean first = true;
for (int i = 0; i < ids.length; i++) {
if (first) {
first = false;
sb.append(" id = :id");
} else {
sb.append(" or id = :id");
}
sb.append(i);
}
Query query = getSession().createQuery(sb.toString());
for (int i = 0; i < ids.length; i++) {
query.setParameter("id" + i, ids[i]);
}
for (Serializable id : (List) query.list()) {
for (int i = 0; i < ids.length; i++) {
if (id.equals(ids[i])) {
ret[i] = true;
// don't break. the same id could be in the list twice.
}
}
}
return ret;
}
protected Filter _getFilterFromExample(Object example) {
return searchProcessor.getFilterFromExample(example);
}
protected Filter _getFilterFromExample(Object example, ExampleOptions options) {
return searchProcessor.getFilterFromExample(example, options);
}
}