com.atlassian.confluence.core.persistence.hibernate

Class HibernateSessionManager

java.lang.Object

com.atlassian.confluence.core.persistence.hibernate.HibernateSessionManager

public class HibernateSessionManager
extends Object

Provides methods to manage objects in the current Hibernate Session. Methods will throw IllegalStateException if there is no active session on the executing thread.

Since:

3.5

See Also:

Session, SessionFactoryUtils.getSession(SessionFactory, boolean)

Constructor Summary

Constructors

Constructor and Description
HibernateSessionManager(net.sf.hibernate.SessionFactory sessionFactory, org.springframework.transaction.PlatformTransactionManager transactionManager)

Method Summary

Modifier and Type	Method and Description
void	evict(Object object) Removes the object and its dependents from the active session.
<I,O> Iterable<O>	executeWithSessionClearing(Iterable<I> input, int batchSize, int expectedTotal, com.google.common.base.Function<I,O> task) Executes a bulk database update in a way that prevents excessive memory usage, by committing the transaction and clearing the session periodically.
<I,O> Iterable<O>	executeWithSessionFlushAndClear(Iterable<I> input, int batchSize, int expectedTotal, com.google.common.base.Function<I,O> task) Reuses the current transaction, to avoid nested transaction issues.
net.sf.hibernate.Session	getSession() Returns the current session.

Methods inherited from class java.lang.Object

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

Constructor Detail

HibernateSessionManager

public HibernateSessionManager(net.sf.hibernate.SessionFactory sessionFactory,
                               org.springframework.transaction.PlatformTransactionManager transactionManager)

Method Detail

getSession

public net.sf.hibernate.Session getSession()

Returns the current session.

Throws:

IllegalStateException - if there is no active session

evict

public void evict(Object object)

Removes the object and its dependents from the active session. Any un-flushed changes will be lost.

This method should be used when processing a large number of Hibernate objects in a read-only fashion.

Throws:

IllegalStateException - if there is no active session

org.springframework.dao.DataAccessException - if there is a problem evicting the object

See Also:

Session.evict(Object)

executeWithSessionClearing

public <I,O> Iterable<O> executeWithSessionClearing(Iterable<I> input,
                                                    int batchSize,
                                                    int expectedTotal,
                                                    com.google.common.base.Function<I,O> task)

Executes a bulk database update in a way that prevents excessive memory usage, by committing the transaction and clearing the session periodically. The provided task is executed once per input item. The commit and session-clearing is done once per batchSize items.

WARNING: the session clearing will discard any unflushed or uncommitted changes made higher in the stack. Batch operations using this method should generally be done in a separate thread or otherwise outside the scope of a request.

Type Parameters:

I - the type of the input items

O - the type of the resulting items, which can be Void

Parameters:

input - the list of items to process

task - the task to execute

batchSize - a transaction will be committed and the session will be cleared after this many input items

expectedTotal - the total number of items, used for logging. A value of 0 indicates expected total is not known.

Returns:

the output of the task

Throws:

IllegalStateException - if there is no active session

org.springframework.dao.DataAccessException - if there is a problem committing changes to the database

executeWithSessionFlushAndClear

public <I,O> Iterable<O> executeWithSessionFlushAndClear(Iterable<I> input,
                                                         int batchSize,
                                                         int expectedTotal,
                                                         com.google.common.base.Function<I,O> task)

Reuses the current transaction, to avoid nested transaction issues.