transactionfactory.java

一个Java持久层类库

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
 * indicated by the @author tags or express copyright attribution
 * statements applied by the authors.  All third-party contributions are
 * distributed under license by Red Hat Middleware LLC.
 *
 * This copyrighted material is made available to anyone wishing to use, modify,
 * copy, or redistribute it subject to the terms and conditions of the GNU
 * Lesser General Public License, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution; if not, write to:
 * Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor
 * Boston, MA  02110-1301  USA
 */
package org.hibernate.transaction;

import java.util.Properties;

import org.hibernate.ConnectionReleaseMode;
import org.hibernate.HibernateException;
import org.hibernate.Transaction;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.jdbc.JDBCContext;

/**
 * Contract for generating Hibernate {@link Transaction} instances.
 * <p/>
 * The concrete implementation to be used is specified by the
 * {@link org.hibernate.cfg.Environment#TRANSACTION_STRATEGY} configuration
 * setting.
 * <p/>
 * Implementors must be threadsafe and should declare a public default constructor.
 *
 * @see Transaction
 *
 * @author Anton van Straaten
 * @author Gavin King
 */
public interface TransactionFactory {

	/**
	 * Callback mechanism; a context is always a {@link org.hibernate.Session}
	 * in the Hibernate usage.
	 */
	public static interface Context {
		public SessionFactoryImplementor getFactory();
		public boolean isClosed();

		public boolean isFlushModeNever();
		public boolean isFlushBeforeCompletionEnabled();
		public void managedFlush();

		public boolean shouldAutoClose();
		public void managedClose();
	}

	/**
	 * Begin a transaction and return the associated <tt>Transaction</tt> instance.
	 *
	 * @param jdbcContext  The jdbc context to which the transaction belongs
	 * @param context The contract regarding the context in which this transaction will operate.
	 * @return Transaction
	 * @throws HibernateException Indicates a problem generating a transaction instance
	 */
	public Transaction createTransaction(JDBCContext jdbcContext, Context context) throws HibernateException;

	/**
	 * Configure from the given properties.
	 *
	 * @param props The configuration properties.
	 * @throws HibernateException Indicates a problem configuring this factory.
	 */
	public void configure(Properties props) throws HibernateException;
	
	/**
	 * Get the default connection release mode.
	 *
	 * @return The default release mode associated with this strategy
	 */
	public ConnectionReleaseMode getDefaultReleaseMode();
	
	/**
	 * Do we require access to the JTA TransactionManager for
	 * this strategy?
	 *
	 * @return True if this strategy requires access to the JTA TransactionManager;
	 * false otherwise.
	 */
	public boolean isTransactionManagerRequired();

	/**
	 * Are all transaction callbacks local to Hibernate Transactions?
	 * Or can the callbacks originate from some other source (e.g. a JTA
	 * Synchronization).
	 *
	 * @return true if callbacks only ever originate from the Hibernate
	 * {@link Transaction}; false otherwise.
	 */
	public boolean areCallbacksLocalToHibernateTransactions();

	/**
	 * Determine whether an underlying transaction is in progress.
	 * <p/>
	 * Mainly this is used in determining whether to register a
	 * synchronization as well as whether or not to circumvent
	 * auto flushing outside transactions.
	 *
	 * @param jdbcContext The JDBC context
	 * @param transactionContext The transaction context
	 * @param transaction The Hibernate transaction
	 * @return true if an underlying transaction is know to be in effect.
	 */
	public boolean isTransactionInProgress(JDBCContext jdbcContext, Context transactionContext, Transaction transaction);
}