protected List<AbstractSession> filterByUserPrincipal(
Collection<AbstractSession> values, Principal userPrincipal) throws IOException {
List<AbstractSession> res = null;
{
if (values != null) {
res = new ArrayList<AbstractSession>();
for (AbstractSession session : values) {
expandSessionPrincipal(session);
}
if (userPrincipal == null) {
for (AbstractSession session : values) {
Principal p = session.getUserPrincipal();
if (p == null) {
res.add(session);
}
}
} else {
for (AbstractSession session : values) {
Principal p = session.getUserPrincipal();
if (PrincipalUtil.equalsIgnoreRealm(userPrincipal, p)) {
res.add(session);
}
}
}
}
}
return res;
}
/**
* INTERNAL: Return the value of the field from the row or a value holder on the query to obtain
* the object. Check for batch + aggregation reading.
*/
public Object valueFromRow(
AbstractRecord row,
JoinedAttributeManager joinManager,
ObjectBuildingQuery query,
AbstractSession executionSession)
throws DatabaseException {
Ref ref = (Ref) row.get(getField());
if (ref == null) {
return null;
}
Struct struct;
try {
((DatabaseAccessor) executionSession.getAccessor()).incrementCallCount(executionSession);
java.sql.Connection connection =
((DatabaseAccessor) executionSession.getAccessor()).getConnection();
struct =
(Struct) executionSession.getPlatform().getRefValue(ref, executionSession, connection);
} catch (java.sql.SQLException exception) {
throw DatabaseException.sqlException(exception, executionSession, false);
}
AbstractRecord targetRow =
((ObjectRelationalDataTypeDescriptor) getReferenceDescriptor())
.buildRowFromStructure(struct);
((DatabaseAccessor) executionSession.getAccessor()).decrementCallCount();
return getReferenceDescriptor().getObjectBuilder().buildObject(query, targetRow, joinManager);
}
/** INTERNAL: Get a value from the object and set that in the respective field of the row. */
@Override
public Object valueFromObject(Object object, DatabaseField field, AbstractSession session) {
// First check if the value can be obtained from the value holder's row.
AbstractRecord referenceRow =
getIndirectionPolicy().extractReferenceRow(getAttributeValueFromObject(object));
if (referenceRow != null) {
Object value = referenceRow.get(field);
// Must ensure the classification to get a cache hit.
try {
value = session.getDatasourcePlatform().convertObject(value, getFieldClassification(field));
} catch (ConversionException e) {
throw ConversionException.couldNotBeConverted(this, getDescriptor(), e);
}
return value;
}
// 2.5.1.6 PWK. added to support batch reading on variable one to ones
Object referenceObject = getRealAttributeValueFromObject(object, session);
String queryKeyName = (String) getSourceToTargetQueryKeyNames().get(field);
ClassDescriptor objectDescriptor = session.getDescriptor(referenceObject.getClass());
DatabaseField targetField =
objectDescriptor.getObjectBuilder().getTargetFieldForQueryKeyName(queryKeyName);
if (targetField == null) {
return null;
}
return objectDescriptor
.getObjectBuilder()
.extractValueFromObjectForField(referenceObject, targetField, session);
}
/**
* PUBLIC: Return a session broker that behaves as a client session broker. An acquire session
* broker is done under the covers on each session inside the session broker, and a new broker is
* returned.
*
* <p>NOTE: when finished with the client broker, it should be releases. See
* releaseClientSessionBroker.
*/
public SessionBroker acquireClientSessionBroker() {
log(SessionLog.FINER, SessionLog.CONNECTION, "acquire_client_session_broker");
SessionBroker clientBroker = copySessionBroker();
clientBroker.parent = this;
clientBroker
.getIdentityMapAccessorInstance()
.setIdentityMapManager(getIdentityMapAccessorInstance().getIdentityMapManager());
clientBroker.commitManager = getCommitManager();
clientBroker.commandManager = getCommandManager();
clientBroker.externalTransactionController = getExternalTransactionController();
clientBroker.setServerPlatform(getServerPlatform());
String sessionName;
AbstractSession serverSession;
Iterator names = this.getSessionsByName().keySet().iterator();
while (names.hasNext()) {
sessionName = (String) names.next();
serverSession = getSessionForName(sessionName);
if (serverSession instanceof org.eclipse.persistence.sessions.server.ServerSession) {
if (serverSession.getProject().hasIsolatedClasses()) {
throw ValidationException.isolatedDataNotSupportedInSessionBroker(sessionName);
}
clientBroker.internalRegisterSession(
sessionName,
((org.eclipse.persistence.sessions.server.ServerSession) serverSession)
.acquireClientSession());
} else {
throw ValidationException.cannotAcquireClientSessionFromSession();
}
}
clientBroker.initializeSequencing();
return clientBroker;
}
/** Delete all of the objects with the matching class. */
public void deleteAllObjects(Class theClass, List objects, AbstractSession session) {
ClassDescriptor descriptor = null;
if (((UnitOfWorkImpl) session).shouldOrderUpdates()) { // bug 331064 - Sort the delete order
objects = sort(theClass, objects);
}
int size = objects.size();
for (int index = 0; index < size; index++) {
Object objectToDelete = objects.get(index);
if (objectToDelete.getClass() == theClass) {
if (descriptor == null) {
descriptor = session.getDescriptor(theClass);
}
// PERF: Get the descriptor query, to avoid extra query creation.
DeleteObjectQuery deleteQuery = descriptor.getQueryManager().getDeleteQuery();
if (deleteQuery == null) {
deleteQuery = new DeleteObjectQuery();
deleteQuery.setDescriptor(descriptor);
} else {
// Ensure original query has been prepared.
deleteQuery.checkPrepare(session, deleteQuery.getTranslationRow());
deleteQuery = (DeleteObjectQuery) deleteQuery.clone();
}
deleteQuery.setIsExecutionClone(true);
deleteQuery.setObject(objectToDelete);
session.executeQuery(deleteQuery);
}
}
}
/**
* delete all of the objects as a single transaction. This should delete the object in the correct
* order to maintain referential integrity.
*/
public void deleteAllObjects(List objects)
throws RuntimeException, DatabaseException, OptimisticLockException {
this.isActive = true;
AbstractSession session = getSession();
session.beginTransaction();
try {
// PERF: Optimize single object case.
if (objects.size() == 1) {
deleteAllObjects(objects.get(0).getClass(), objects, session);
} else {
List commitOrder = getCommitOrder();
for (int orderIndex = commitOrder.size() - 1; orderIndex >= 0; orderIndex--) {
Class theClass = (Class) commitOrder.get(orderIndex);
deleteAllObjects(theClass, objects, session);
}
}
session.commitTransaction();
} catch (RuntimeException exception) {
try {
session.rollbackTransaction();
} catch (Exception ignore) {
}
throw exception;
} finally {
reinitialize();
this.isActive = false;
}
}
/**
* INTERNAL: Return the results from exeucting the database query. the arguments should be a
* database row with raw data values. Find the correct child session to broker the query to, and
* return the result of the session executing the query.
*/
public Object internalExecuteQuery(DatabaseQuery query, AbstractRecord row)
throws DatabaseException, QueryException {
AbstractSession sessionByQuery = getSessionForQuery(query);
// Note, this disables local profilers.
return sessionByQuery.internalExecuteQuery(query, row);
}
/**
* Commit all of the objects of the class type in the change set. This allows for the order of the
* classes to be processed optimally.
*/
protected void commitNewObjectsForClassWithChangeSet(
UnitOfWorkChangeSet uowChangeSet, Class theClass) {
Map<ObjectChangeSet, ObjectChangeSet> newObjectChangesList =
uowChangeSet.getNewObjectChangeSets().get(theClass);
if (newObjectChangesList != null) { // may be no changes for that class type.
AbstractSession session = getSession();
ClassDescriptor descriptor = session.getDescriptor(theClass);
List<ObjectChangeSet> newChangeSets = new ArrayList(newObjectChangesList.values());
int size = newChangeSets.size();
for (int index = 0; index < size; index++) {
ObjectChangeSet changeSetToWrite = newChangeSets.get(index);
Object objectToWrite = changeSetToWrite.getUnitOfWorkClone();
if (!isProcessedCommit(objectToWrite)) {
// PERF: Get the descriptor query, to avoid extra query creation.
InsertObjectQuery commitQuery = descriptor.getQueryManager().getInsertQuery();
if (commitQuery == null) {
commitQuery = new InsertObjectQuery();
commitQuery.setDescriptor(descriptor);
} else {
// Ensure original query has been prepared.
commitQuery.checkPrepare(session, commitQuery.getTranslationRow());
commitQuery = (InsertObjectQuery) commitQuery.clone();
}
commitQuery.setIsExecutionClone(true);
commitQuery.setObjectChangeSet(changeSetToWrite);
commitQuery.setObject(objectToWrite);
commitQuery.cascadeOnlyDependentParts();
commitQuery.setModifyRow(null);
session.executeQuery(commitQuery);
}
uowChangeSet.putNewObjectInChangesList(changeSetToWrite, session);
}
}
}
/**
* PUBLIC: set the integrityChecker. IntegrityChecker holds all the ClassDescriptor Exceptions.
*/
public void setIntegrityChecker(IntegrityChecker integrityChecker) {
super.setIntegrityChecker(integrityChecker);
for (Iterator sessionEnum = getSessionsByName().values().iterator(); sessionEnum.hasNext(); ) {
AbstractSession session = (AbstractSession) sessionEnum.next();
session.setIntegrityChecker(integrityChecker);
}
}
/**
* PUBLIC: Set the message log.
*
* @see #logMessages()
*/
public void setLog(Writer log) {
super.setLog(log);
for (Iterator sessionEnum = getSessionsByName().values().iterator(); sessionEnum.hasNext(); ) {
AbstractSession session = (AbstractSession) sessionEnum.next();
session.setLog(log);
}
}
/**
* PUBLIC: Set the profiler for the session. This allows for performance operations to be
* profiled.
*/
public void setProfiler(SessionProfiler profiler) {
super.setProfiler(profiler);
for (Iterator sessionEnum = getSessionsByName().values().iterator(); sessionEnum.hasNext(); ) {
AbstractSession session = (AbstractSession) sessionEnum.next();
session.setProfiler(profiler);
}
}
/** PUBLIC: Return if this session is a server session broker. */
public boolean isServerSessionBroker() {
for (Iterator sessionEnum = getSessionsByName().values().iterator(); sessionEnum.hasNext(); ) {
AbstractSession session = (AbstractSession) sessionEnum.next();
if (session.isServerSession()) {
return true;
}
}
return false;
}
/**
* PUBLIC: Release the session. This does nothing by default, but allows for other sessions such
* as the ClientSession to do something.
*/
public void release() {
if (isClientSessionBroker()) {
log(SessionLog.FINER, SessionLog.CONNECTION, "releasing_client_session_broker");
}
AbstractSession session;
for (Iterator enumtr = getSessionsByName().values().iterator(); enumtr.hasNext(); ) {
session = (AbstractSession) enumtr.next();
session.release();
}
super.release();
}
/**
* INTERNAL: This method notifies the accessor that a particular sets of writes has completed.
* This notification can be used for such thing as flushing the batch mechanism
*/
public void writesCompleted() {
for (Iterator sessionEnum = getSessionsByName().values().iterator(); sessionEnum.hasNext(); ) {
AbstractSession session = (AbstractSession) sessionEnum.next();
if (!session.isConnected()) {
throw DatabaseException.databaseAccessorNotConnected();
}
}
for (Iterator sessionEnum = getSessionsByName().values().iterator(); sessionEnum.hasNext(); ) {
AbstractSession session = (AbstractSession) sessionEnum.next();
session.writesCompleted();
}
}
/**
* INTERNAL: Commit the transaction on all child sessions. This assumes that the commit of the
* transaction will not fail because all of the modification has already taken place and no errors
* would have occurred.
*/
protected void basicCommitTransaction() throws DatabaseException {
// Do one last check it make sure that all sessions are still connected.
for (Iterator sessionEnum = getSessionsByName().values().iterator(); sessionEnum.hasNext(); ) {
AbstractSession session = (AbstractSession) sessionEnum.next();
if (!session.isConnected()) {
throw DatabaseException.databaseAccessorNotConnected();
}
}
for (Iterator sessionEnum = getSessionsByName().values().iterator(); sessionEnum.hasNext(); ) {
AbstractSession session = (AbstractSession) sessionEnum.next();
session.commitTransaction();
}
}
/** PUBLIC: Return if all sessions are still connected to the database. */
public boolean isConnected() {
if ((getSessionsByName() == null) || (getSessionsByName().isEmpty())) {
return false;
}
for (Iterator sessionEnum = getSessionsByName().values().iterator(); sessionEnum.hasNext(); ) {
AbstractSession session = (AbstractSession) sessionEnum.next();
if (!session.isConnected()) {
return false;
}
}
return true;
}
/** INTERNAL: Rollback the transaction on all child sessions. */
protected void basicRollbackTransaction() throws DatabaseException {
DatabaseException globalException = null;
for (Iterator sessionEnum = getSessionsByName().values().iterator(); sessionEnum.hasNext(); ) {
AbstractSession session = (AbstractSession) sessionEnum.next();
try {
session.rollbackTransaction();
} catch (DatabaseException exception) {
globalException = exception;
}
}
if (globalException != null) {
throw globalException;
}
}
protected void expandSessionPrincipal(AbstractSession session) throws IOException {
if (session != null) {
String id = session.getId();
HttpSession httpSession = lookupHttpSessionById.get(id);
// Set 'userPrincipal' upon session:
{
if (httpSession != null) {
Principal userPrincipal = PrincipalSessionDecorator.getPrincipal(httpSession);
if (userPrincipal != null) {
session.setUserPrincipal(userPrincipal);
}
}
}
}
}
/**
* INTERNAL: Register the session under its name. All of the session's descriptors must have
* already been registered. The session should not be connected and descriptors should not be
* initialized. Used for client session broker
*/
public void internalRegisterSession(String name, AbstractSession session) {
// Bug#3911318 Removed session brokers and sessions point to the same descriptors.
// They don't need to be reassigned. Also the code to add read only classes has been removed
// because client broker and server broker point to the same project.
session.setIsInBroker(true);
getSessionsByName().put(name, session);
session.setBroker(this);
session.setName(name);
/* // The keys/classes must also be used as some descriptors may be under multiple classes.
Iterator classes = session.getDescriptors().keySet().iterator();
while (classes.hasNext()) {
Class descriptorClass = (Class)classes.next();
getSessionNamesByClass().put(descriptorClass, session);
}
*/ }
/**
* PUBLIC: Register the session under its name. All of the session's descriptors must have already
* been registered. The session should not be connected and descriptors should not be initialized.
*/
public void registerSession(String name, AbstractSession session) {
session.setIsInBroker(true);
getSessionsByName().put(name, session);
session.setBroker(this);
session.setName(name);
// The keys/classes must also be used as some descriptors may be under multiple classes.
Iterator descriptors = session.getDescriptors().values().iterator();
Iterator classes = session.getDescriptors().keySet().iterator();
while (descriptors.hasNext()) {
ClassDescriptor descriptor = (ClassDescriptor) descriptors.next();
Class descriptorClass = (Class) classes.next();
getSessionNamesByClass().put(descriptorClass, name);
getDescriptors().put(descriptorClass, descriptor);
}
}
/**
* INTERNAL: Compare the references of the two objects are the same, not the objects themselves.
* Used for independent relationships. This is used for testing and validation purposes.
*
* <p>Must get separate fields for the objects because we may be adding a different class to the
* attribute because of the interface
*/
@Override
protected boolean compareObjectsWithoutPrivateOwned(
Object firstObject, Object secondObject, AbstractSession session) {
Object firstPrivateObject = getRealAttributeValueFromObject(firstObject, session);
Object secondPrivateObject = getRealAttributeValueFromObject(secondObject, session);
if ((firstPrivateObject == null) && (secondPrivateObject == null)) {
return true;
}
if ((firstPrivateObject == null) || (secondPrivateObject == null)) {
return false;
}
if (firstPrivateObject.getClass() != secondPrivateObject.getClass()) {
return false;
}
Iterator targetKeys = getSourceToTargetQueryKeyNames().values().iterator();
ClassDescriptor descriptor = session.getDescriptor(firstPrivateObject.getClass());
ClassDescriptor descriptor2 = session.getDescriptor(secondPrivateObject.getClass());
while (targetKeys.hasNext()) {
String queryKey = (String) targetKeys.next();
DatabaseField field = descriptor.getObjectBuilder().getFieldForQueryKeyName(queryKey);
Object firstObjectField =
descriptor
.getObjectBuilder()
.extractValueFromObjectForField(firstPrivateObject, field, session);
DatabaseField field2 = descriptor2.getObjectBuilder().getFieldForQueryKeyName(queryKey);
Object secondObjectField =
descriptor2
.getObjectBuilder()
.extractValueFromObjectForField(secondPrivateObject, field2, session);
if (!((firstObjectField == null) && (secondObjectField == null))) {
if ((firstObjectField == null) || (secondObjectField == null)) {
return false;
}
if (!firstObjectField.equals(secondObjectField)) {
return false;
}
}
}
return true;
}
/** INTERNAL: Acquires a special historical session for reading objects as of a past time. */
public org.eclipse.persistence.sessions.Session acquireHistoricalSession(AsOfClause clause)
throws ValidationException {
if (isServerSessionBroker()) {
throw ValidationException.cannotAcquireHistoricalSession();
}
// ? logMessage("acquire_client_session_broker", (Object[])null);
SessionBroker historicalBroker = copySessionBroker();
String sessionName;
AbstractSession session;
Iterator names = this.getSessionsByName().keySet().iterator();
while (names.hasNext()) {
sessionName = (String) names.next();
session = getSessionForName(sessionName);
historicalBroker.registerSession(sessionName, session.acquireHistoricalSession(clause));
}
return historicalBroker;
}
protected void expandSession(AbstractSession session) throws IOException {
if (session != null) {
String id = session.getId();
HttpSession httpSession = lookupHttpSessionById.get(id);
// Set 'timeLastAccess' upon session:
{
if (httpSession != null) {
Date timeLastAccess = new Date(httpSession.getLastAccessedTime());
session.setTimeLastAccess(timeLastAccess);
}
}
expandSessionPrincipal(session);
// Set 'requestURI' upon session:
{
if (httpSession != null) {
List<String> requestURIs = RequestURISessionDecorator.getRequestURIs(httpSession);
if (requestURIs != null) {
Collections.reverse(requestURIs); // reverse the order!
session.setRequestURIs(requestURIs);
}
}
}
// Set 'properties' upon session:
{
if (httpSession != null) {
Map<String, Object> m = PropertiesSessionDecorator.getProperties(httpSession);
if (m != null) {
Properties properties = convertProperties(m);
session.setProperties(properties);
}
}
}
}
}
/**
* Commit changed of the objects of the class type in the change set. This allows for the order of
* the classes to be processed optimally.
*/
protected void commitChangedObjectsForClassWithChangeSet(
UnitOfWorkChangeSet uowChangeSet, Class theClass) {
Map<ObjectChangeSet, ObjectChangeSet> objectChangesList =
uowChangeSet.getObjectChanges().get(theClass);
if (objectChangesList != null) { // may be no changes for that class type.
ClassDescriptor descriptor = null;
AbstractSession session = getSession();
Collection<ObjectChangeSet> changes = objectChangesList.values();
if (((UnitOfWorkImpl) session).shouldOrderUpdates()) {
changes = new ArrayList(objectChangesList.values());
Collections.sort((List) changes);
}
for (ObjectChangeSet changeSetToWrite : changes) {
Object objectToWrite = changeSetToWrite.getUnitOfWorkClone();
if (descriptor == null) {
descriptor = session.getDescriptor(objectToWrite);
}
if (!isProcessedCommit(objectToWrite)) {
// Commit and resume on failure can cause a new change set to be in existing, so need to
// check here.
WriteObjectQuery commitQuery = null;
if (changeSetToWrite.isNew()) {
commitQuery = new InsertObjectQuery();
} else {
commitQuery = new UpdateObjectQuery();
}
commitQuery.setIsExecutionClone(true);
commitQuery.setDescriptor(descriptor);
commitQuery.setObjectChangeSet(changeSetToWrite);
commitQuery.setObject(objectToWrite);
commitQuery.cascadeOnlyDependentParts();
// removed checking session type to set cascade level
// will always be a unitOfWork so we need to cascade dependent parts
session.executeQuery(commitQuery);
}
}
}
}
/** INTERNAL: Return the implementor for a specified type */
protected Object getImplementorForType(Object type, AbstractSession session) {
if (type == null) {
return getTypeIndicatorTranslation().get(Helper.getNullWrapper());
}
// Must ensure the type is the same, i.e. Integer != BigDecimal.
try {
type = session.getDatasourcePlatform().convertObject(type, getTypeField().getType());
} catch (ConversionException e) {
throw ConversionException.couldNotBeConverted(this, getDescriptor(), e);
}
return getTypeIndicatorTranslation().get(type);
}
// bug 331064 - Sort the delete order based on PKs.
private List sort(Class theClass, List objects) {
ClassDescriptor descriptor = session.getDescriptor(theClass);
org.eclipse.persistence.internal.descriptors.ObjectBuilder objectBuilder =
descriptor.getObjectBuilder();
int size = objects.size();
TreeMap sortedObjects = new TreeMap();
for (int index = 0; index < size; index++) {
Object objectToDelete = objects.get(index);
if (objectToDelete.getClass() == theClass) {
sortedObjects.put(
objectBuilder.extractPrimaryKeyFromObject(objectToDelete, session), objectToDelete);
}
}
return new ArrayList(sortedObjects.values());
}
/** INTERNAL: Initialize the mapping. */
public void initialize(AbstractSession session) throws DescriptorException {
setReferenceDescriptor(session.getDescriptor(getReferenceClass()));
if (referenceDescriptor == null) {
throw DescriptorException.descriptorIsMissing(getReferenceClass().getName(), this);
}
// For bug 2730536 convert the field to be an ObjectRelationalDatabaseField.
ObjectRelationalDatabaseField field = (ObjectRelationalDatabaseField) getField();
field.setSqlType(java.sql.Types.REF);
if (referenceDescriptor instanceof ObjectRelationalDataTypeDescriptor) {
field.setSqlTypeName(
((ObjectRelationalDataTypeDescriptor) referenceDescriptor).getStructureName());
}
setField(getDescriptor().buildField(getField()));
setFields(collectFields());
// Ref mapping requires native connection in WLS as the Ref is wrapped.
getDescriptor().setIsNativeConnectionRequired(true);
}
/**
* INTERNAL: Get a value from the object and set that in the respective field of the row. If the
* mapping id target foreign key, you must only write the type into the roe, the rest will be
* updated when the object itself is written
*/
@Override
public void writeFromObjectIntoRowWithChangeRecord(
ChangeRecord changeRecord, AbstractRecord record, AbstractSession session) {
if (isReadOnly()) {
return;
}
ObjectChangeSet changeSet =
(ObjectChangeSet) ((ObjectReferenceChangeRecord) changeRecord).getNewValue();
if (changeSet == null) {
writeFromNullObjectIntoRow(record);
} else {
Object referenceObject = changeSet.getUnitOfWorkClone();
if (isForeignKeyRelationship()) {
Enumeration sourceFields = getForeignKeyFields().elements();
ClassDescriptor descriptor = session.getDescriptor(referenceObject.getClass());
while (sourceFields.hasMoreElements()) {
DatabaseField sourceKey = (DatabaseField) sourceFields.nextElement();
String targetQueryKey = (String) getSourceToTargetQueryKeyNames().get(sourceKey);
DatabaseField targetKeyField =
descriptor.getObjectBuilder().getFieldForQueryKeyName(targetQueryKey);
if (targetKeyField == null) {
throw DescriptorException.variableOneToOneMappingIsNotDefinedProperly(
this, descriptor, targetQueryKey);
}
Object referenceValue =
descriptor
.getObjectBuilder()
.extractValueFromObjectForField(referenceObject, targetKeyField, session);
record.put(sourceKey, referenceValue);
}
}
if (getTypeField() != null) {
record.put(getTypeField(), getTypeForImplementor(referenceObject.getClass()));
}
}
}
/** INTERNAL: Begin the transaction on all child sessions. */
protected void basicBeginTransaction() throws DatabaseException {
for (Iterator sessionEnum = getSessionsByName().values().iterator(); sessionEnum.hasNext(); ) {
AbstractSession session = (AbstractSession) sessionEnum.next();
session.beginTransaction();
}
}
/**
* INTERNAL: Gets the session which this query will be executed on. Generally will be called
* immediately before the call is translated, which is immediately before session.executeCall.
*
* <p>Since the execution session also knows the correct datasource platform to execute on, it is
* often used in the mappings where the platform is needed for type conversion, or where calls are
* translated.
*
* <p>Is also the session with the accessor. Will return a ClientSession if it is in transaction
* and has a write connection.
*
* @return a session with a live accessor
* @param query may store session name or reference class for brokers case
*/
public AbstractSession getExecutionSession(DatabaseQuery query) {
AbstractSession sessionByQuery = getSessionForQuery(query);
// Always forward to a registered session.
return sessionByQuery.getExecutionSession(query);
}