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Spring Framework example source code file (JdoTransactionManager.java)

This example Spring Framework source code file (JdoTransactionManager.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Spring Framework tags/keywords

connectionholder, datasource, jdbc, jdo, jdo, jdotransactionmanager, jdotransactionobject, jdotransactionobject, object, persistencemanager, persistencemanager, persistencemanagerholder, persistencemanagerholder, sql, suspendedresourcesholder

The Spring Framework JdoTransactionManager.java source code

/*
 * Copyright 2002-2008 the original author or authors.
 *
 * 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 org.springframework.orm.jdo;

import javax.jdo.JDOException;
import javax.jdo.PersistenceManager;
import javax.jdo.PersistenceManagerFactory;
import javax.jdo.Transaction;
import javax.sql.DataSource;

import org.springframework.beans.factory.InitializingBean;
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.datasource.ConnectionHandle;
import org.springframework.jdbc.datasource.ConnectionHolder;
import org.springframework.jdbc.datasource.JdbcTransactionObjectSupport;
import org.springframework.jdbc.datasource.TransactionAwareDataSourceProxy;
import org.springframework.transaction.CannotCreateTransactionException;
import org.springframework.transaction.IllegalTransactionStateException;
import org.springframework.transaction.TransactionDefinition;
import org.springframework.transaction.TransactionException;
import org.springframework.transaction.TransactionSystemException;
import org.springframework.transaction.support.AbstractPlatformTransactionManager;
import org.springframework.transaction.support.DefaultTransactionStatus;
import org.springframework.transaction.support.ResourceTransactionManager;
import org.springframework.transaction.support.TransactionSynchronizationManager;

/**
 * {@link org.springframework.transaction.PlatformTransactionManager} implementation
 * for a single JDO {@link javax.jdo.PersistenceManagerFactory}. Binds a JDO
 * PersistenceManager from the specified factory to the thread, potentially allowing
 * for one thread-bound PersistenceManager per factory.
 * {@link PersistenceManagerFactoryUtils} and {@link JdoTemplate} are aware of
 * thread-bound persistence managers and participate in such transactions automatically.
 * Using either of those (or going through a {@link TransactionAwarePersistenceManagerFactoryProxy}
 * is required for JDO access code supporting this transaction management mechanism.
 *
 * <p>This transaction manager is appropriate for applications that use a single
 * JDO PersistenceManagerFactory for transactional data access. JTA (usually through
 * {@link org.springframework.transaction.jta.JtaTransactionManager}) is necessary
 * for accessing multiple transactional resources within the same transaction.
 * Note that you need to configure your JDO provider accordingly in order to make
 * it participate in JTA transactions.
 *
 * <p>This transaction manager also supports direct DataSource access within a
 * transaction (i.e. plain JDBC code working with the same DataSource).
 * This allows for mixing services which access JDO and services which use plain
 * JDBC (without being aware of JDO)! Application code needs to stick to the
 * same simple Connection lookup pattern as with
 * {@link org.springframework.jdbc.datasource.DataSourceTransactionManager}
 * (i.e. {@link org.springframework.jdbc.datasource.DataSourceUtils#getConnection}
 * or going through a
 * {@link org.springframework.jdbc.datasource.TransactionAwareDataSourceProxy}).
 *
 * <p>Note: To be able to register a DataSource's Connection for plain JDBC code,
 * this instance needs to be aware of the DataSource ({@link #setDataSource}).
 * The given DataSource should obviously match the one used by the given
 * PersistenceManagerFactory. This transaction manager will autodetect the DataSource
 * that acts as "connectionFactory" of the PersistenceManagerFactory, so you usually
 * don't need to explicitly specify the "dataSource" property.
 *
 * <p>On JDBC 3.0, this transaction manager supports nested transactions via JDBC 3.0
 * Savepoints. The {@link #setNestedTransactionAllowed} "nestedTransactionAllowed"}
 * flag defaults to "false", though, as nested transactions will just apply to the
 * JDBC Connection, not to the JDO PersistenceManager and its cached objects.
 * You can manually set the flag to "true" if you want to use nested transactions
 * for JDBC access code which participates in JDO transactions (provided that your
 * JDBC driver supports Savepoints). <i>Note that JDO itself does not support
 * nested transactions! Hence, do not expect JDO access code to semantically
 * participate in a nested transaction.</i>
 *
 * @author Juergen Hoeller
 * @since 03.06.2003
 * @see #setPersistenceManagerFactory
 * @see #setDataSource
 * @see javax.jdo.PersistenceManagerFactory#getConnectionFactory
 * @see LocalPersistenceManagerFactoryBean
 * @see PersistenceManagerFactoryUtils#getPersistenceManager
 * @see PersistenceManagerFactoryUtils#releasePersistenceManager
 * @see JdoTemplate
 * @see TransactionAwarePersistenceManagerFactoryProxy
 * @see org.springframework.jdbc.datasource.DataSourceUtils#getConnection
 * @see org.springframework.jdbc.datasource.DataSourceUtils#releaseConnection
 * @see org.springframework.jdbc.core.JdbcTemplate
 * @see org.springframework.jdbc.datasource.DataSourceTransactionManager
 * @see org.springframework.transaction.jta.JtaTransactionManager
 */
public class JdoTransactionManager extends AbstractPlatformTransactionManager
		implements ResourceTransactionManager, InitializingBean {

	private PersistenceManagerFactory persistenceManagerFactory;

	private DataSource dataSource;

	private boolean autodetectDataSource = true;

	private JdoDialect jdoDialect;


	/**
	 * Create a new JdoTransactionManager instance.
	 * A PersistenceManagerFactory has to be set to be able to use it.
	 * @see #setPersistenceManagerFactory
	 */
	public JdoTransactionManager() {
	}

	/**
	 * Create a new JdoTransactionManager instance.
	 * @param pmf PersistenceManagerFactory to manage transactions for
	 */
	public JdoTransactionManager(PersistenceManagerFactory pmf) {
		this.persistenceManagerFactory = pmf;
		afterPropertiesSet();
	}


	/**
	 * Set the PersistenceManagerFactory that this instance should manage transactions for.
	 * <p>The PersistenceManagerFactory specified here should be the target
	 * PersistenceManagerFactory to manage transactions for, not a
	 * TransactionAwarePersistenceManagerFactoryProxy. Only data access
	 * code may work with TransactionAwarePersistenceManagerFactoryProxy, while the
	 * transaction manager needs to work on the underlying target PersistenceManagerFactory.
	 * @see TransactionAwarePersistenceManagerFactoryProxy
	 */
	public void setPersistenceManagerFactory(PersistenceManagerFactory pmf) {
		this.persistenceManagerFactory = pmf;
	}

	/**
	 * Return the PersistenceManagerFactory that this instance should manage transactions for.
	 */
	public PersistenceManagerFactory getPersistenceManagerFactory() {
		return this.persistenceManagerFactory;
	}

	/**
	 * Set the JDBC DataSource that this instance should manage transactions for.
   * The DataSource should match the one used by the JDO PersistenceManagerFactory:
	 * for example, you could specify the same JNDI DataSource for both.
	 * <p>If the PersistenceManagerFactory uses a DataSource as connection factory,
	 * the DataSource will be autodetected: You can still explictly specify the
	 * DataSource, but you don't need to in this case.
	 * <p>A transactional JDBC Connection for this DataSource will be provided to
	 * application code accessing this DataSource directly via DataSourceUtils
	 * or JdbcTemplate. The Connection will be taken from the JDO PersistenceManager.
	 * <p>Note that you need to use a JDO dialect for a specific JDO provider to
	 * allow for exposing JDO transactions as JDBC transactions.
	 * <p>The DataSource specified here should be the target DataSource to manage
	 * transactions for, not a TransactionAwareDataSourceProxy. Only data access
	 * code may work with TransactionAwareDataSourceProxy, while the transaction
	 * manager needs to work on the underlying target DataSource. If there's
	 * nevertheless a TransactionAwareDataSourceProxy passed in, it will be
	 * unwrapped to extract its target DataSource.
	 * @see #setAutodetectDataSource
	 * @see #setJdoDialect
	 * @see javax.jdo.PersistenceManagerFactory#getConnectionFactory
	 * @see org.springframework.jdbc.datasource.TransactionAwareDataSourceProxy
	 * @see org.springframework.jdbc.datasource.DataSourceUtils
	 * @see org.springframework.jdbc.core.JdbcTemplate
	 */
	public void setDataSource(DataSource dataSource) {
		if (dataSource instanceof TransactionAwareDataSourceProxy) {
			// If we got a TransactionAwareDataSourceProxy, we need to perform transactions
			// for its underlying target DataSource, else data access code won't see
			// properly exposed transactions (i.e. transactions for the target DataSource).
			this.dataSource = ((TransactionAwareDataSourceProxy) dataSource).getTargetDataSource();
		}
		else {
			this.dataSource = dataSource;
		}
	}

	/**
	 * Return the JDBC DataSource that this instance manages transactions for.
	 */
	public DataSource getDataSource() {
		return this.dataSource;
	}

	/**
	 * Set whether to autodetect a JDBC DataSource used by the JDO PersistenceManagerFactory,
	 * as returned by the <code>getConnectionFactory() method. Default is "true".
	 * <p>Can be turned off to deliberately ignore an available DataSource,
	 * to not expose JDO transactions as JDBC transactions for that DataSource.
	 * @see #setDataSource
	 * @see javax.jdo.PersistenceManagerFactory#getConnectionFactory
	 */
	public void setAutodetectDataSource(boolean autodetectDataSource) {
		this.autodetectDataSource = autodetectDataSource;
	}

	/**
	 * Set the JDO dialect to use for this transaction manager.
	 * <p>The dialect object can be used to retrieve the underlying JDBC connection
	 * and thus allows for exposing JDO transactions as JDBC transactions.
	 * @see JdoDialect#getJdbcConnection
	 */
	public void setJdoDialect(JdoDialect jdoDialect) {
		this.jdoDialect = jdoDialect;
	}

	/**
	 * Return the JDO dialect to use for this transaction manager.
	 * <p>Creates a default one for the specified PersistenceManagerFactory if none set.
	 */
	public JdoDialect getJdoDialect() {
		if (this.jdoDialect == null) {
			this.jdoDialect = new DefaultJdoDialect();
		}
		return this.jdoDialect;
	}

	/**
	 * Eagerly initialize the JDO dialect, creating a default one
	 * for the specified PersistenceManagerFactory if none set.
	 * Auto-detect the PersistenceManagerFactory's DataSource, if any.
	 */
	public void afterPropertiesSet() {
		if (getPersistenceManagerFactory() == null) {
			throw new IllegalArgumentException("Property 'persistenceManagerFactory' is required");
		}
		// Build default JdoDialect if none explicitly specified.
		if (this.jdoDialect == null) {
			this.jdoDialect = new DefaultJdoDialect(getPersistenceManagerFactory().getConnectionFactory());
		}

		// Check for DataSource as connection factory.
		if (this.autodetectDataSource && getDataSource() == null) {
			Object pmfcf = getPersistenceManagerFactory().getConnectionFactory();
			if (pmfcf instanceof DataSource) {
				// Use the PersistenceManagerFactory's DataSource for exposing transactions to JDBC code.
				this.dataSource = (DataSource) pmfcf;
				if (logger.isInfoEnabled()) {
					logger.info("Using DataSource [" + this.dataSource +
							"] of JDO PersistenceManagerFactory for JdoTransactionManager");
				}
			}
		}
	}


	public Object getResourceFactory() {
		return getPersistenceManagerFactory();
	}

	protected Object doGetTransaction() {
		JdoTransactionObject txObject = new JdoTransactionObject();
		txObject.setSavepointAllowed(isNestedTransactionAllowed());

		PersistenceManagerHolder pmHolder = (PersistenceManagerHolder)
				TransactionSynchronizationManager.getResource(getPersistenceManagerFactory());
		if (pmHolder != null) {
			if (logger.isDebugEnabled()) {
				logger.debug("Found thread-bound PersistenceManager [" +
						pmHolder.getPersistenceManager() + "] for JDO transaction");
			}
			txObject.setPersistenceManagerHolder(pmHolder, false);
		}

		if (getDataSource() != null) {
			ConnectionHolder conHolder = (ConnectionHolder)
					TransactionSynchronizationManager.getResource(getDataSource());
			txObject.setConnectionHolder(conHolder);
		}

		return txObject;
	}

	protected boolean isExistingTransaction(Object transaction) {
		return ((JdoTransactionObject) transaction).hasTransaction();
	}

	protected void doBegin(Object transaction, TransactionDefinition definition) {
		JdoTransactionObject txObject = (JdoTransactionObject) transaction;

		if (txObject.hasConnectionHolder() && !txObject.getConnectionHolder().isSynchronizedWithTransaction()) {
			throw new IllegalTransactionStateException(
					"Pre-bound JDBC Connection found! JdoTransactionManager does not support " +
					"running within DataSourceTransactionManager if told to manage the DataSource itself. " +
					"It is recommended to use a single JdoTransactionManager for all transactions " +
					"on a single DataSource, no matter whether JDO or JDBC access.");
		}

		PersistenceManager pm = null;

		try {
			if (txObject.getPersistenceManagerHolder() == null ||
					txObject.getPersistenceManagerHolder().isSynchronizedWithTransaction()) {
				PersistenceManager newPm = getPersistenceManagerFactory().getPersistenceManager();
				if (logger.isDebugEnabled()) {
					logger.debug("Opened new PersistenceManager [" + newPm + "] for JDO transaction");
				}
				txObject.setPersistenceManagerHolder(new PersistenceManagerHolder(newPm), true);
			}

			pm = txObject.getPersistenceManagerHolder().getPersistenceManager();

			// Delegate to JdoDialect for actual transaction begin.
			Object transactionData = getJdoDialect().beginTransaction(pm.currentTransaction(), definition);
			txObject.setTransactionData(transactionData);

			// Register transaction timeout.
			int timeout = determineTimeout(definition);
			if (timeout != TransactionDefinition.TIMEOUT_DEFAULT) {
				txObject.getPersistenceManagerHolder().setTimeoutInSeconds(timeout);
			}

			// Register the JDO PersistenceManager's JDBC Connection for the DataSource, if set.
			if (getDataSource() != null) {
				ConnectionHandle conHandle = getJdoDialect().getJdbcConnection(pm, definition.isReadOnly());
				if (conHandle != null) {
					ConnectionHolder conHolder = new ConnectionHolder(conHandle);
					if (timeout != TransactionDefinition.TIMEOUT_DEFAULT) {
						conHolder.setTimeoutInSeconds(timeout);
					}
					if (logger.isDebugEnabled()) {
						logger.debug("Exposing JDO transaction as JDBC transaction [" + conHolder.getConnectionHandle() + "]");
					}
					TransactionSynchronizationManager.bindResource(getDataSource(), conHolder);
					txObject.setConnectionHolder(conHolder);
				}
				else {
					if (logger.isDebugEnabled()) {
						logger.debug("Not exposing JDO transaction [" + pm + "] as JDBC transaction because JdoDialect [" +
								getJdoDialect() + "] does not support JDBC Connection retrieval");
					}
				}
			}

			// Bind the persistence manager holder to the thread.
			if (txObject.isNewPersistenceManagerHolder()) {
				TransactionSynchronizationManager.bindResource(
						getPersistenceManagerFactory(), txObject.getPersistenceManagerHolder());
			}
			txObject.getPersistenceManagerHolder().setSynchronizedWithTransaction(true);
		}

		catch (TransactionException ex) {
			closePersistenceManagerAfterFailedBegin(txObject);
			throw ex;
		}
		catch (Exception ex) {
			closePersistenceManagerAfterFailedBegin(txObject);
			throw new CannotCreateTransactionException("Could not open JDO PersistenceManager for transaction", ex);
		}
	}

	/**
	 * Close the current transaction's EntityManager.
	 * Called after a transaction begin attempt failed.
	 * @param txObject the current transaction
	 */
	protected void closePersistenceManagerAfterFailedBegin(JdoTransactionObject txObject) {
		if (txObject.isNewPersistenceManagerHolder()) {
			PersistenceManager pm = txObject.getPersistenceManagerHolder().getPersistenceManager();
			try {
				if (pm.currentTransaction().isActive()) {
					pm.currentTransaction().rollback();
				}
			}
			catch (Throwable ex) {
				logger.debug("Could not rollback PersistenceManager after failed transaction begin", ex);
			}
			finally {
				PersistenceManagerFactoryUtils.releasePersistenceManager(pm, getPersistenceManagerFactory());
			}
		}
	}

	protected Object doSuspend(Object transaction) {
		JdoTransactionObject txObject = (JdoTransactionObject) transaction;
		txObject.setPersistenceManagerHolder(null, false);
		PersistenceManagerHolder persistenceManagerHolder = (PersistenceManagerHolder)
				TransactionSynchronizationManager.unbindResource(getPersistenceManagerFactory());
		txObject.setConnectionHolder(null);
		ConnectionHolder connectionHolder = null;
		if (getDataSource() != null && TransactionSynchronizationManager.hasResource(getDataSource())) {
			connectionHolder = (ConnectionHolder) TransactionSynchronizationManager.unbindResource(getDataSource());
		}
		return new SuspendedResourcesHolder(persistenceManagerHolder, connectionHolder);
	}

	protected void doResume(Object transaction, Object suspendedResources) {
		SuspendedResourcesHolder resourcesHolder = (SuspendedResourcesHolder) suspendedResources;
		TransactionSynchronizationManager.bindResource(
				getPersistenceManagerFactory(), resourcesHolder.getPersistenceManagerHolder());
		if (getDataSource() != null && resourcesHolder.getConnectionHolder() != null) {
			TransactionSynchronizationManager.bindResource(getDataSource(), resourcesHolder.getConnectionHolder());
		}
	}

	/**
	 * This implementation returns "true": a JDO2 commit will properly handle
	 * transactions that have been marked rollback-only at a global level.
	 */
	protected boolean shouldCommitOnGlobalRollbackOnly() {
		return true;
	}

	protected void doCommit(DefaultTransactionStatus status) {
		JdoTransactionObject txObject = (JdoTransactionObject) status.getTransaction();
		if (status.isDebug()) {
			logger.debug("Committing JDO transaction on PersistenceManager [" +
					txObject.getPersistenceManagerHolder().getPersistenceManager() + "]");
		}
		try {
			Transaction tx = txObject.getPersistenceManagerHolder().getPersistenceManager().currentTransaction();
			tx.commit();
		}
		catch (JDOException ex) {
			// Assumably failed to flush changes to database.
			throw convertJdoAccessException(ex);
		}
	}

	protected void doRollback(DefaultTransactionStatus status) {
		JdoTransactionObject txObject = (JdoTransactionObject) status.getTransaction();
		if (status.isDebug()) {
			logger.debug("Rolling back JDO transaction on PersistenceManager [" +
					txObject.getPersistenceManagerHolder().getPersistenceManager() + "]");
		}
		try {
			Transaction tx = txObject.getPersistenceManagerHolder().getPersistenceManager().currentTransaction();
			if (tx.isActive()) {
				tx.rollback();
			}
		}
		catch (JDOException ex) {
			throw new TransactionSystemException("Could not roll back JDO transaction", ex);
		}
	}

	protected void doSetRollbackOnly(DefaultTransactionStatus status) {
		JdoTransactionObject txObject = (JdoTransactionObject) status.getTransaction();
		if (status.isDebug()) {
			logger.debug("Setting JDO transaction on PersistenceManager [" +
					txObject.getPersistenceManagerHolder().getPersistenceManager() + "] rollback-only");
		}
		txObject.setRollbackOnly();
	}

	protected void doCleanupAfterCompletion(Object transaction) {
		JdoTransactionObject txObject = (JdoTransactionObject) transaction;

		// Remove the persistence manager holder from the thread.
		if (txObject.isNewPersistenceManagerHolder()) {
			TransactionSynchronizationManager.unbindResource(getPersistenceManagerFactory());
		}
		txObject.getPersistenceManagerHolder().clear();

		// Remove the JDBC connection holder from the thread, if exposed.
		if (txObject.hasConnectionHolder()) {
			TransactionSynchronizationManager.unbindResource(getDataSource());
			try {
				getJdoDialect().releaseJdbcConnection(txObject.getConnectionHolder().getConnectionHandle(),
						txObject.getPersistenceManagerHolder().getPersistenceManager());
			}
			catch (Throwable ex) {
				// Just log it, to keep a transaction-related exception.
				logger.debug("Could not release JDBC connection after transaction", ex);
			}
		}

		getJdoDialect().cleanupTransaction(txObject.getTransactionData());

		if (txObject.isNewPersistenceManagerHolder()) {
			PersistenceManager pm = txObject.getPersistenceManagerHolder().getPersistenceManager();
			if (logger.isDebugEnabled()) {
				logger.debug("Closing JDO PersistenceManager [" + pm + "] after transaction");
			}
			PersistenceManagerFactoryUtils.releasePersistenceManager(pm, getPersistenceManagerFactory());
		}
		else {
			logger.debug("Not closing pre-bound JDO PersistenceManager after transaction");
		}
	}

	/**
	 * Convert the given JDOException to an appropriate exception from the
	 * <code>org.springframework.dao hierarchy.
	 * <p>Default implementation delegates to the JdoDialect.
	 * May be overridden in subclasses.
	 * @param ex JDOException that occured
	 * @return the corresponding DataAccessException instance
	 * @see JdoDialect#translateException
	 */
	protected DataAccessException convertJdoAccessException(JDOException ex) {
		return getJdoDialect().translateException(ex);
	}


	/**
	 * JDO transaction object, representing a PersistenceManagerHolder.
	 * Used as transaction object by JdoTransactionManager.
	 */
	private static class JdoTransactionObject extends JdbcTransactionObjectSupport {

		private PersistenceManagerHolder persistenceManagerHolder;

		private boolean newPersistenceManagerHolder;

		private Object transactionData;

		public void setPersistenceManagerHolder(
				PersistenceManagerHolder persistenceManagerHolder, boolean newPersistenceManagerHolder) {
			this.persistenceManagerHolder = persistenceManagerHolder;
			this.newPersistenceManagerHolder = newPersistenceManagerHolder;
		}

		public PersistenceManagerHolder getPersistenceManagerHolder() {
			return persistenceManagerHolder;
		}

		public boolean isNewPersistenceManagerHolder() {
			return newPersistenceManagerHolder;
		}

		public boolean hasTransaction() {
			return (this.persistenceManagerHolder != null && this.persistenceManagerHolder.isTransactionActive());
		}

		public void setTransactionData(Object transactionData) {
			this.transactionData = transactionData;
			this.persistenceManagerHolder.setTransactionActive(true);
		}

		public Object getTransactionData() {
			return transactionData;
		}

		public void setRollbackOnly() {
			Transaction tx = this.persistenceManagerHolder.getPersistenceManager().currentTransaction();
			if (tx.isActive()) {
				tx.setRollbackOnly();
			}
			if (hasConnectionHolder()) {
				getConnectionHolder().setRollbackOnly();
			}
		}

		public boolean isRollbackOnly() {
			Transaction tx = this.persistenceManagerHolder.getPersistenceManager().currentTransaction();
			return tx.getRollbackOnly();
		}
	}


	/**
	 * Holder for suspended resources.
	 * Used internally by <code>doSuspend and doResume.
	 */
	private static class SuspendedResourcesHolder {

		private final PersistenceManagerHolder persistenceManagerHolder;

		private final ConnectionHolder connectionHolder;

		private SuspendedResourcesHolder(PersistenceManagerHolder pmHolder, ConnectionHolder conHolder) {
			this.persistenceManagerHolder = pmHolder;
			this.connectionHolder = conHolder;
		}

		private PersistenceManagerHolder getPersistenceManagerHolder() {
			return this.persistenceManagerHolder;
		}

		private ConnectionHolder getConnectionHolder() {
			return this.connectionHolder;
		}
	}

}

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