https://github.com/spring-projects/spring-framework: Spring Transaction (Spring IO)
  • Juergen Hoeller 
/*
 * Copyright 2002-2020 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
 *
 *      https://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.transaction.jta;

import java.util.List;

import javax.naming.NamingException;

import com.ibm.websphere.uow.UOWSynchronizationRegistry;
import com.ibm.wsspi.uow.UOWAction;
import com.ibm.wsspi.uow.UOWActionException;
import com.ibm.wsspi.uow.UOWException;
import com.ibm.wsspi.uow.UOWManager;
import com.ibm.wsspi.uow.UOWManagerFactory;

import org.springframework.lang.Nullable;
import org.springframework.transaction.IllegalTransactionStateException;
import org.springframework.transaction.InvalidTimeoutException;
import org.springframework.transaction.NestedTransactionNotSupportedException;
import org.springframework.transaction.TransactionDefinition;
import org.springframework.transaction.TransactionException;
import org.springframework.transaction.TransactionSystemException;
import org.springframework.transaction.support.CallbackPreferringPlatformTransactionManager;
import org.springframework.transaction.support.DefaultTransactionStatus;
import org.springframework.transaction.support.SmartTransactionObject;
import org.springframework.transaction.support.TransactionCallback;
import org.springframework.transaction.support.TransactionSynchronization;
import org.springframework.transaction.support.TransactionSynchronizationManager;
import org.springframework.transaction.support.TransactionSynchronizationUtils;
import org.springframework.util.Assert;
import org.springframework.util.ReflectionUtils;


WebSphere-specific PlatformTransactionManager implementation that delegates to a UOWManager instance, obtained from WebSphere's JNDI environment. This allows Spring to leverage the full power of the WebSphere transaction coordinator, including transaction suspension, in a manner that is perfectly compliant with officially supported WebSphere API. 
The CallbackPreferringPlatformTransactionManager interface implemented by this class indicates that callers should preferably pass in a TransactionCallback through the execute method, which will be handled through the callback-based WebSphere UOWManager API instead of through standard JTA API (UserTransaction / TransactionManager). This avoids the use of the non-public javax.transaction.TransactionManager API on WebSphere, staying within supported WebSphere API boundaries. 
This transaction manager implementation derives from Spring's standard JtaTransactionManager, inheriting the capability to support programmatic transaction demarcation via getTransaction / commit / rollback calls through a JTA UserTransaction handle, for callers that do not use the TransactionCallback-based execute method. However, transaction suspension is not supported in this getTransaction style (unless you explicitly specify a setTransactionManager reference, despite the official WebSphere recommendations). Use the execute style for any code that might require transaction suspension. 
This transaction manager is compatible with WebSphere 6.1.0.9 and above.
The default JNDI location for the UOWManager is "java:comp/websphere/UOWManager".
If the location happens to differ according to your WebSphere documentation,
simply specify the actual location through this transaction manager's
"uowManagerName" bean property.

NOTE: This JtaTransactionManager is intended to refine specific transaction
demarcation behavior on Spring's side. It will happily co-exist with independently
configured WebSphere transaction strategies in your persistence provider, with no
need to specifically connect those setups in any way.

Author:Juergen Hoeller
See Also:
Since:2.5
/**
 * WebSphere-specific PlatformTransactionManager implementation that delegates
 * to a {@link com.ibm.wsspi.uow.UOWManager} instance, obtained from WebSphere's
 * JNDI environment. This allows Spring to leverage the full power of the WebSphere
 * transaction coordinator, including transaction suspension, in a manner that is
 * perfectly compliant with officially supported WebSphere API.
 *
 * <p>The {@link CallbackPreferringPlatformTransactionManager} interface
 * implemented by this class indicates that callers should preferably pass in
 * a {@link TransactionCallback} through the {@link #execute} method, which
 * will be handled through the callback-based WebSphere UOWManager API instead
 * of through standard JTA API (UserTransaction / TransactionManager). This avoids
 * the use of the non-public {@code javax.transaction.TransactionManager}
 * API on WebSphere, staying within supported WebSphere API boundaries.
 *
 * <p>This transaction manager implementation derives from Spring's standard
 * {@link JtaTransactionManager}, inheriting the capability to support programmatic
 * transaction demarcation via {@code getTransaction} / {@code commit} /
 * {@code rollback} calls through a JTA UserTransaction handle, for callers
 * that do not use the TransactionCallback-based {@link #execute} method. However,
 * transaction suspension is <i>not</i> supported in this {@code getTransaction}
 * style (unless you explicitly specify a {@link #setTransactionManager} reference,
 * despite the official WebSphere recommendations). Use the {@link #execute} style
 * for any code that might require transaction suspension.
 *
 * <p>This transaction manager is compatible with WebSphere 6.1.0.9 and above.
 * The default JNDI location for the UOWManager is "java:comp/websphere/UOWManager".
 * If the location happens to differ according to your WebSphere documentation,
 * simply specify the actual location through this transaction manager's
 * "uowManagerName" bean property.
 *
 * <p><b>NOTE: This JtaTransactionManager is intended to refine specific transaction
 * demarcation behavior on Spring's side. It will happily co-exist with independently
 * configured WebSphere transaction strategies in your persistence provider, with no
 * need to specifically connect those setups in any way.</b>
 *
 * @author Juergen Hoeller
 * @since 2.5
 * @see #setUowManager
 * @see #setUowManagerName
 * @see com.ibm.wsspi.uow.UOWManager
 */
@SuppressWarnings("serial")
public class WebSphereUowTransactionManager extends JtaTransactionManager
		implements CallbackPreferringPlatformTransactionManager {

	
Default JNDI location for the WebSphere UOWManager.

See Also:
  • setUowManagerName
/**
	 * Default JNDI location for the WebSphere UOWManager.
	 * @see #setUowManagerName
	 */
	public static final String DEFAULT_UOW_MANAGER_NAME = "java:comp/websphere/UOWManager";


	@Nullable
	private UOWManager uowManager;

	@Nullable
	private String uowManagerName;


	
Create a new WebSphereUowTransactionManager.

/**
	 * Create a new WebSphereUowTransactionManager.
	 */
	public WebSphereUowTransactionManager() {
		setAutodetectTransactionManager(false);
	}

	
Create a new WebSphereUowTransactionManager for the given UOWManager.

Params:
  • uowManager – the WebSphere UOWManager to use as direct reference
/**
	 * Create a new WebSphereUowTransactionManager for the given UOWManager.
	 * @param uowManager the WebSphere UOWManager to use as direct reference
	 */
	public WebSphereUowTransactionManager(UOWManager uowManager) {
		this();
		this.uowManager = uowManager;
	}


	
Set the WebSphere UOWManager to use as direct reference.

Typically just used for test setups; in a Java EE environment,
the UOWManager will always be fetched from JNDI.

See Also:
  • setUserTransactionName
/**
	 * Set the WebSphere UOWManager to use as direct reference.
	 * <p>Typically just used for test setups; in a Java EE environment,
	 * the UOWManager will always be fetched from JNDI.
	 * @see #setUserTransactionName
	 */
	public void setUowManager(UOWManager uowManager) {
		this.uowManager = uowManager;
	}

	
Set the JNDI name of the WebSphere UOWManager.
The default "java:comp/websphere/UOWManager" is used if not set.

See Also:
  • DEFAULT_USER_TRANSACTION_NAME
  • setUowManager
/**
	 * Set the JNDI name of the WebSphere UOWManager.
	 * The default "java:comp/websphere/UOWManager" is used if not set.
	 * @see #DEFAULT_USER_TRANSACTION_NAME
	 * @see #setUowManager
	 */
	public void setUowManagerName(String uowManagerName) {
		this.uowManagerName = uowManagerName;
	}


	@Override
	public void afterPropertiesSet() throws TransactionSystemException {
		initUserTransactionAndTransactionManager();

		// Fetch UOWManager handle from JNDI, if necessary.
		if (this.uowManager == null) {
			if (this.uowManagerName != null) {
				this.uowManager = lookupUowManager(this.uowManagerName);
			}
			else {
				this.uowManager = lookupDefaultUowManager();
			}
		}
	}

	
Look up the WebSphere UOWManager in JNDI via the configured name.

Params:
  • uowManagerName – the JNDI name of the UOWManager
Throws:
See Also:
Returns:the UOWManager object
/**
	 * Look up the WebSphere UOWManager in JNDI via the configured name.
	 * @param uowManagerName the JNDI name of the UOWManager
	 * @return the UOWManager object
	 * @throws TransactionSystemException if the JNDI lookup failed
	 * @see #setJndiTemplate
	 * @see #setUowManagerName
	 */
	protected UOWManager lookupUowManager(String uowManagerName) throws TransactionSystemException {
		try {
			if (logger.isDebugEnabled()) {
				logger.debug("Retrieving WebSphere UOWManager from JNDI location [" + uowManagerName + "]");
			}
			return getJndiTemplate().lookup(uowManagerName, UOWManager.class);
		}
		catch (NamingException ex) {
			throw new TransactionSystemException(
					"WebSphere UOWManager is not available at JNDI location [" + uowManagerName + "]", ex);
		}
	}

	
Obtain the WebSphere UOWManager from the default JNDI location
"java:comp/websphere/UOWManager".

Throws:
See Also:
  • setJndiTemplate
Returns:the UOWManager object
/**
	 * Obtain the WebSphere UOWManager from the default JNDI location
	 * "java:comp/websphere/UOWManager".
	 * @return the UOWManager object
	 * @throws TransactionSystemException if the JNDI lookup failed
	 * @see #setJndiTemplate
	 */
	protected UOWManager lookupDefaultUowManager() throws TransactionSystemException {
		try {
			logger.debug("Retrieving WebSphere UOWManager from default JNDI location [" + DEFAULT_UOW_MANAGER_NAME + "]");
			return getJndiTemplate().lookup(DEFAULT_UOW_MANAGER_NAME, UOWManager.class);
		}
		catch (NamingException ex) {
			logger.debug("WebSphere UOWManager is not available at default JNDI location [" +
					DEFAULT_UOW_MANAGER_NAME + "] - falling back to UOWManagerFactory lookup");
			return UOWManagerFactory.getUOWManager();
		}
	}

	private UOWManager obtainUOWManager() {
		Assert.state(this.uowManager != null, "No UOWManager set");
		return this.uowManager;
	}


	
Registers the synchronizations as interposed JTA Synchronization on the UOWManager.

/**
	 * Registers the synchronizations as interposed JTA Synchronization on the UOWManager.
	 */
	@Override
	protected void doRegisterAfterCompletionWithJtaTransaction(
			JtaTransactionObject txObject, List<TransactionSynchronization> synchronizations) {

		obtainUOWManager().registerInterposedSynchronization(new JtaAfterCompletionSynchronization(synchronizations));
	}

	
Returns true since WebSphere ResourceAdapters (as exposed in JNDI) implicitly perform transaction enlistment if the MessageEndpointFactory's isDeliveryTransacted method returns true. In that case we'll simply skip the createTransaction call. 
See Also:
/**
	 * Returns {@code true} since WebSphere ResourceAdapters (as exposed in JNDI)
	 * implicitly perform transaction enlistment if the MessageEndpointFactory's
	 * {@code isDeliveryTransacted} method returns {@code true}.
	 * In that case we'll simply skip the {@link #createTransaction} call.
	 * @see javax.resource.spi.endpoint.MessageEndpointFactory#isDeliveryTransacted
	 * @see org.springframework.jca.endpoint.AbstractMessageEndpointFactory
	 * @see TransactionFactory#createTransaction
	 */
	@Override
	public boolean supportsResourceAdapterManagedTransactions() {
		return true;
	}


	@Override
	@Nullable
	public <T> T execute(@Nullable TransactionDefinition definition, TransactionCallback<T> callback)
			throws TransactionException {

		// Use defaults if no transaction definition given.
		TransactionDefinition def = (definition != null ? definition : TransactionDefinition.withDefaults());

		if (def.getTimeout() < TransactionDefinition.TIMEOUT_DEFAULT) {
			throw new InvalidTimeoutException("Invalid transaction timeout", def.getTimeout());
		}

		UOWManager uowManager = obtainUOWManager();
		int pb = def.getPropagationBehavior();
		boolean existingTx = (uowManager.getUOWStatus() != UOWSynchronizationRegistry.UOW_STATUS_NONE &&
				uowManager.getUOWType() != UOWSynchronizationRegistry.UOW_TYPE_LOCAL_TRANSACTION);

		int uowType = UOWSynchronizationRegistry.UOW_TYPE_GLOBAL_TRANSACTION;
		boolean joinTx = false;
		boolean newSynch = false;

		if (existingTx) {
			if (pb == TransactionDefinition.PROPAGATION_NEVER) {
				throw new IllegalTransactionStateException(
						"Transaction propagation 'never' but existing transaction found");
			}
			if (pb == TransactionDefinition.PROPAGATION_NESTED) {
				throw new NestedTransactionNotSupportedException(
						"Transaction propagation 'nested' not supported for WebSphere UOW transactions");
			}
			if (pb == TransactionDefinition.PROPAGATION_SUPPORTS ||
					pb == TransactionDefinition.PROPAGATION_REQUIRED ||
					pb == TransactionDefinition.PROPAGATION_MANDATORY) {
				joinTx = true;
				newSynch = (getTransactionSynchronization() != SYNCHRONIZATION_NEVER);
			}
			else if (pb == TransactionDefinition.PROPAGATION_NOT_SUPPORTED) {
				uowType = UOWSynchronizationRegistry.UOW_TYPE_LOCAL_TRANSACTION;
				newSynch = (getTransactionSynchronization() == SYNCHRONIZATION_ALWAYS);
			}
			else {
				newSynch = (getTransactionSynchronization() != SYNCHRONIZATION_NEVER);
			}
		}
		else {
			if (pb == TransactionDefinition.PROPAGATION_MANDATORY) {
				throw new IllegalTransactionStateException(
						"Transaction propagation 'mandatory' but no existing transaction found");
			}
			if (pb == TransactionDefinition.PROPAGATION_SUPPORTS ||
					pb == TransactionDefinition.PROPAGATION_NOT_SUPPORTED ||
					pb == TransactionDefinition.PROPAGATION_NEVER) {
				uowType = UOWSynchronizationRegistry.UOW_TYPE_LOCAL_TRANSACTION;
				newSynch = (getTransactionSynchronization() == SYNCHRONIZATION_ALWAYS);
			}
			else {
				newSynch = (getTransactionSynchronization() != SYNCHRONIZATION_NEVER);
			}
		}

		boolean debug = logger.isDebugEnabled();
		if (debug) {
			logger.debug("Creating new transaction with name [" + def.getName() + "]: " + def);
		}
		SuspendedResourcesHolder suspendedResources = (!joinTx ? suspend(null) : null);
		UOWActionAdapter<T> action = null;
		try {
			boolean actualTransaction = (uowType == UOWManager.UOW_TYPE_GLOBAL_TRANSACTION);
			if (actualTransaction && def.getTimeout() > TransactionDefinition.TIMEOUT_DEFAULT) {
				uowManager.setUOWTimeout(uowType, def.getTimeout());
			}
			if (debug) {
				logger.debug("Invoking WebSphere UOW action: type=" + uowType + ", join=" + joinTx);
			}
			action = new UOWActionAdapter<>(def, callback, actualTransaction, !joinTx, newSynch, debug);
			uowManager.runUnderUOW(uowType, joinTx, action);
			if (debug) {
				logger.debug("Returned from WebSphere UOW action: type=" + uowType + ", join=" + joinTx);
			}
			return action.getResult();
		}
		catch (UOWException | UOWActionException ex) {
			TransactionSystemException tse =
					new TransactionSystemException("UOWManager transaction processing failed", ex);
			Throwable appEx = action.getException();
			if (appEx != null) {
				logger.error("Application exception overridden by rollback exception", appEx);
				tse.initApplicationException(appEx);
			}
			throw tse;
		}
		finally {
			if (suspendedResources != null) {
				resume(null, suspendedResources);
			}
		}
	}


	
Adapter that executes the given Spring transaction within the WebSphere UOWAction shape.

/**
	 * Adapter that executes the given Spring transaction within the WebSphere UOWAction shape.
	 */
	private class UOWActionAdapter<T> implements UOWAction, SmartTransactionObject {

		private final TransactionDefinition definition;

		private final TransactionCallback<T> callback;

		private final boolean actualTransaction;

		private final boolean newTransaction;

		private final boolean newSynchronization;

		private boolean debug;

		@Nullable
		private T result;

		@Nullable
		private Throwable exception;

		public UOWActionAdapter(TransactionDefinition definition, TransactionCallback<T> callback,
				boolean actualTransaction, boolean newTransaction, boolean newSynchronization, boolean debug) {

			this.definition = definition;
			this.callback = callback;
			this.actualTransaction = actualTransaction;
			this.newTransaction = newTransaction;
			this.newSynchronization = newSynchronization;
			this.debug = debug;
		}

		@Override
		public void run() {
			UOWManager uowManager = obtainUOWManager();
			DefaultTransactionStatus status = prepareTransactionStatus(
					this.definition, (this.actualTransaction ? this : null),
					this.newTransaction, this.newSynchronization, this.debug, null);
			try {
				this.result = this.callback.doInTransaction(status);
				triggerBeforeCommit(status);
			}
			catch (Throwable ex) {
				this.exception = ex;
				if (status.isDebug()) {
					logger.debug("Rolling back on application exception from transaction callback", ex);
				}
				uowManager.setRollbackOnly();
			}
			finally {
				if (status.isLocalRollbackOnly()) {
					if (status.isDebug()) {
						logger.debug("Transaction callback has explicitly requested rollback");
					}
					uowManager.setRollbackOnly();
				}
				triggerBeforeCompletion(status);
				if (status.isNewSynchronization()) {
					List<TransactionSynchronization> synchronizations = TransactionSynchronizationManager.getSynchronizations();
					TransactionSynchronizationManager.clear();
					if (!synchronizations.isEmpty()) {
						uowManager.registerInterposedSynchronization(new JtaAfterCompletionSynchronization(synchronizations));
					}
				}
			}
		}

		@Nullable
		public T getResult() {
			if (this.exception != null) {
				ReflectionUtils.rethrowRuntimeException(this.exception);
			}
			return this.result;
		}

		@Nullable
		public Throwable getException() {
			return this.exception;
		}

		@Override
		public boolean isRollbackOnly() {
			return obtainUOWManager().getRollbackOnly();
		}

		@Override
		public void flush() {
			TransactionSynchronizationUtils.triggerFlush();
		}
	}

}