Introduce TransactionDefinition.withDefaults() shortcut

Such a static unmodifiable TransactionDefinition with defaults can be used for getTransaction(null) calls, now also possible for getReactiveTransaction. Furthermore, it can be used for a simple TransactionalOperator.create(ReactiveTransactionManager) method without an internal dependency on the transaction.support package.

See gh-22646

Author: jhoeller

spring-context-support/src/main/java/org/springframework/scheduling/quartz/SchedulerAccessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -41,9 +41,9 @@
 import org.springframework.core.io.ResourceLoader;
 import org.springframework.lang.Nullable;
 import org.springframework.transaction.PlatformTransactionManager;
+import org.springframework.transaction.TransactionDefinition;
 import org.springframework.transaction.TransactionException;
 import org.springframework.transaction.TransactionStatus;
-import org.springframework.transaction.support.DefaultTransactionDefinition;
 
 /**
  * Common base class for accessing a Quartz Scheduler, i.e. for registering jobs,
@@ -207,7 +207,7 @@ public void setResourceLoader(ResourceLoader resourceLoader) {
 	protected void registerJobsAndTriggers() throws SchedulerException {
 		TransactionStatus transactionStatus = null;
 		if (this.transactionManager != null) {
-			transactionStatus = this.transactionManager.getTransaction(new DefaultTransactionDefinition());
+			transactionStatus = this.transactionManager.getTransaction(TransactionDefinition.withDefaults());
 		}
 
 		try {

spring-tx/src/main/java/org/springframework/transaction/ReactiveTransactionManager.java

@@ -18,6 +18,8 @@
 
 import reactor.core.publisher.Mono;
 
+import org.springframework.lang.Nullable;
+
 /**
  * This is the central interface in Spring's reactive transaction infrastructure.
  * Applications can use this directly, but it is not primarily meant as API:
@@ -27,6 +29,8 @@
  * @author Mark Paluch
  * @author Juergen Hoeller
  * @since 5.2
+ * @see org.springframework.transaction.reactive.TransactionalOperator
+ * @see org.springframework.transaction.interceptor.TransactionInterceptor
  */
 public interface ReactiveTransactionManager extends TransactionManager {
 
@@ -53,7 +57,8 @@ public interface ReactiveTransactionManager extends TransactionManager {
 	 * @see TransactionDefinition#getTimeout
 	 * @see TransactionDefinition#isReadOnly
 	 */
-	Mono<ReactiveTransaction> getReactiveTransaction(TransactionDefinition definition) throws TransactionException;
+	Mono<ReactiveTransaction> getReactiveTransaction(@Nullable TransactionDefinition definition)
+			throws TransactionException;
 
 	/**
 	 * Commit the given transaction, with regard to its status. If the transaction

spring-tx/src/main/java/org/springframework/transaction/StaticTransactionDefinition.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2002-2019 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;
+
+/**
+ * A static unmodifiable transaction definition.
+ *
+ * @author Juergen Hoeller
+ * @since 5.2
+ * @see TransactionDefinition#withDefaults()
+ */
+final class StaticTransactionDefinition implements TransactionDefinition {
+
+	static final StaticTransactionDefinition INSTANCE = new StaticTransactionDefinition();
+
+	private StaticTransactionDefinition() {
+	}
+
+}

spring-tx/src/main/java/org/springframework/transaction/TransactionDefinition.java

@@ -195,11 +195,14 @@ public interface TransactionDefinition {
 	 * Return the propagation behavior.
 	 * <p>Must return one of the {@code PROPAGATION_XXX} constants
 	 * defined on {@link TransactionDefinition this interface}.
+	 * <p>The default is {@link #PROPAGATION_REQUIRED}.
 	 * @return the propagation behavior
 	 * @see #PROPAGATION_REQUIRED
 	 * @see org.springframework.transaction.support.TransactionSynchronizationManager#isActualTransactionActive()
 	 */
-	int getPropagationBehavior();
+	default int getPropagationBehavior() {
+		return PROPAGATION_REQUIRED;
+	}
 
 	/**
 	 * Return the isolation level.
@@ -212,13 +215,16 @@ public interface TransactionDefinition {
 	 * "true" on your transaction manager if you'd like isolation level declarations
 	 * to get rejected when participating in an existing transaction with a different
 	 * isolation level.
-	 * <p>Note that a transaction manager that does not support custom isolation levels
-	 * will throw an exception when given any other level than {@link #ISOLATION_DEFAULT}.
+	 * <p>The default is {@link #ISOLATION_DEFAULT}. Note that a transaction manager
+	 * that does not support custom isolation levels will throw an exception when
+	 * given any other level than {@link #ISOLATION_DEFAULT}.
 	 * @return the isolation level
 	 * @see #ISOLATION_DEFAULT
 	 * @see org.springframework.transaction.support.AbstractPlatformTransactionManager#setValidateExistingTransaction
 	 */
-	int getIsolationLevel();
+	default int getIsolationLevel() {
+		return ISOLATION_DEFAULT;
+	}
 
 	/**
 	 * Return the transaction timeout.
@@ -228,9 +234,12 @@ public interface TransactionDefinition {
 	 * transactions.
 	 * <p>Note that a transaction manager that does not support timeouts will throw
 	 * an exception when given any other timeout than {@link #TIMEOUT_DEFAULT}.
+	 * <p>The default is {@link #TIMEOUT_DEFAULT}.
 	 * @return the transaction timeout
 	 */
-	int getTimeout();
+	default int getTimeout() {
+		return TIMEOUT_DEFAULT;
+	}
 
 	/**
 	 * Return whether to optimize as a read-only transaction.
@@ -245,22 +254,41 @@ public interface TransactionDefinition {
 	 * A transaction manager which cannot interpret the read-only hint will
 	 * <i>not</i> throw an exception when asked for a read-only transaction.
 	 * @return {@code true} if the transaction is to be optimized as read-only
+	 * ({@code false} by default)
 	 * @see org.springframework.transaction.support.TransactionSynchronization#beforeCommit(boolean)
 	 * @see org.springframework.transaction.support.TransactionSynchronizationManager#isCurrentTransactionReadOnly()
 	 */
-	boolean isReadOnly();
+	default boolean isReadOnly() {
+		return false;
+	}
 
 	/**
 	 * Return the name of this transaction. Can be {@code null}.
 	 * <p>This will be used as the transaction name to be shown in a
 	 * transaction monitor, if applicable (for example, WebLogic's).
 	 * <p>In case of Spring's declarative transactions, the exposed name will be
 	 * the {@code fully-qualified class name + "." + method name} (by default).
-	 * @return the name of this transaction
+	 * @return the name of this transaction ({@code null} by default}
 	 * @see org.springframework.transaction.interceptor.TransactionAspectSupport
 	 * @see org.springframework.transaction.support.TransactionSynchronizationManager#getCurrentTransactionName()
 	 */
 	@Nullable
-	String getName();
+	default String getName() {
+		return null;
+	}
+
+
+	// Static builder methods
+
+	/**
+	 * Return an unmodifiable {@code TransactionDefinition} with defaults.
+	 * <p>For customization purposes, use the modifiable
+	 * {@link org.springframework.transaction.support.DefaultTransactionDefinition}
+	 * instead.
+	 * @since 5.2
+	 */
+	static TransactionDefinition withDefaults() {
+		return StaticTransactionDefinition.INSTANCE;
+	}
 
 }

spring-tx/src/main/java/org/springframework/transaction/jta/WebSphereUowTransactionManager.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -34,7 +34,6 @@
 import org.springframework.transaction.TransactionException;
 import org.springframework.transaction.TransactionSystemException;
 import org.springframework.transaction.support.CallbackPreferringPlatformTransactionManager;
-import org.springframework.transaction.support.DefaultTransactionDefinition;
 import org.springframework.transaction.support.DefaultTransactionStatus;
 import org.springframework.transaction.support.SmartTransactionObject;
 import org.springframework.transaction.support.TransactionCallback;
@@ -233,17 +232,15 @@ public boolean supportsResourceAdapterManagedTransactions() {
 	public <T> T execute(@Nullable TransactionDefinition definition, TransactionCallback<T> callback)
 			throws TransactionException {
 
-		if (definition == null) {
-			// Use defaults if no transaction definition given.
-			definition = new DefaultTransactionDefinition();
-		}
+		// Use defaults if no transaction definition given.
+		TransactionDefinition def = (definition != null ? definition : TransactionDefinition.withDefaults());
 
-		if (definition.getTimeout() < TransactionDefinition.TIMEOUT_DEFAULT) {
-			throw new InvalidTimeoutException("Invalid transaction timeout", definition.getTimeout());
+		if (def.getTimeout() < TransactionDefinition.TIMEOUT_DEFAULT) {
+			throw new InvalidTimeoutException("Invalid transaction timeout", def.getTimeout());
 		}
 
 		UOWManager uowManager = obtainUOWManager();
-		int pb = definition.getPropagationBehavior();
+		int pb = def.getPropagationBehavior();
 		boolean existingTx = (uowManager.getUOWStatus() != UOWSynchronizationRegistry.UOW_STATUS_NONE &&
 				uowManager.getUOWType() != UOWSynchronizationRegistry.UOW_TYPE_LOCAL_TRANSACTION);
 
@@ -292,19 +289,19 @@ else if (pb == TransactionDefinition.PROPAGATION_NOT_SUPPORTED) {
 
 		boolean debug = logger.isDebugEnabled();
 		if (debug) {
-			logger.debug("Creating new transaction with name [" + definition.getName() + "]: " + definition);
+			logger.debug("Creating new transaction with name [" + def.getName() + "]: " + def);
 		}
 		SuspendedResourcesHolder suspendedResources = (!joinTx ? suspend(null) : null);
 		UOWActionAdapter<T> action = null;
 		try {
-			if (definition.getTimeout() > TransactionDefinition.TIMEOUT_DEFAULT) {
-				uowManager.setUOWTimeout(uowType, definition.getTimeout());
+			if (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<>(
-					definition, callback, (uowType == UOWManager.UOW_TYPE_GLOBAL_TRANSACTION), !joinTx, newSynch, debug);
+					def, callback, (uowType == UOWManager.UOW_TYPE_GLOBAL_TRANSACTION), !joinTx, newSynch, debug);
 			uowManager.runUnderUOW(uowType, joinTx, action);
 			if (debug) {
 				logger.debug("Returned from WebSphere UOW action: type=" + uowType + ", join=" + joinTx);

spring-tx/src/main/java/org/springframework/transaction/reactive/AbstractReactiveTransactionManager.java

@@ -95,7 +95,12 @@ public abstract class AbstractReactiveTransactionManager implements ReactiveTran
 	 * @see #doBegin
 	 */
 	@Override
-	public final Mono<ReactiveTransaction> getReactiveTransaction(TransactionDefinition definition) throws TransactionException {
+	public final Mono<ReactiveTransaction> getReactiveTransaction(@Nullable TransactionDefinition definition)
+			throws TransactionException {
+
+		// Use defaults if no transaction definition given.
+		TransactionDefinition def = (definition != null ? definition : TransactionDefinition.withDefaults());
+
 		return TransactionSynchronizationManager.currentTransaction()
 				.flatMap(synchronizationManager -> {
 
@@ -106,22 +111,22 @@ public final Mono<ReactiveTransaction> getReactiveTransaction(TransactionDefinit
 
 			if (isExistingTransaction(transaction)) {
 				// Existing transaction found -> check propagation behavior to find out how to behave.
-				return handleExistingTransaction(synchronizationManager, definition, transaction, debugEnabled);
+				return handleExistingTransaction(synchronizationManager, def, transaction, debugEnabled);
 			}
 
 			// Check definition settings for new transaction.
-			if (definition.getTimeout() < TransactionDefinition.TIMEOUT_DEFAULT) {
-				return Mono.error(new InvalidTimeoutException("Invalid transaction timeout", definition.getTimeout()));
+			if (def.getTimeout() < TransactionDefinition.TIMEOUT_DEFAULT) {
+				return Mono.error(new InvalidTimeoutException("Invalid transaction timeout", def.getTimeout()));
 			}
 
 			// No existing transaction found -> check propagation behavior to find out how to proceed.
-			if (definition.getPropagationBehavior() == TransactionDefinition.PROPAGATION_MANDATORY) {
+			if (def.getPropagationBehavior() == TransactionDefinition.PROPAGATION_MANDATORY) {
 				return Mono.error(new IllegalTransactionStateException(
 						"No existing transaction found for transaction marked with propagation 'mandatory'"));
 			}
-			else if (definition.getPropagationBehavior() == TransactionDefinition.PROPAGATION_REQUIRED ||
-					definition.getPropagationBehavior() == TransactionDefinition.PROPAGATION_REQUIRES_NEW ||
-					definition.getPropagationBehavior() == TransactionDefinition.PROPAGATION_NESTED) {
+			else if (def.getPropagationBehavior() == TransactionDefinition.PROPAGATION_REQUIRED ||
+					def.getPropagationBehavior() == TransactionDefinition.PROPAGATION_REQUIRES_NEW ||
+					def.getPropagationBehavior() == TransactionDefinition.PROPAGATION_NESTED) {
 
 				return TransactionContextManager.currentContext()
 						.map(TransactionSynchronizationManager::new)
@@ -131,14 +136,14 @@ else if (definition.getPropagationBehavior() == TransactionDefinition.PROPAGATIO
 								.defaultIfEmpty(Optional.empty())
 								.flatMap(suspendedResources -> {
 							if (debugEnabled) {
-								logger.debug("Creating new transaction with name [" + definition.getName() + "]: " + definition);
+								logger.debug("Creating new transaction with name [" + def.getName() + "]: " + def);
 							}
 							return Mono.defer(() -> {
 								GenericReactiveTransaction status = newReactiveTransaction(
-										nestedSynchronizationManager, definition, transaction, true,
+										nestedSynchronizationManager, def, transaction, true,
 										debugEnabled, suspendedResources.orElse(null));
-								return doBegin(nestedSynchronizationManager, transaction, definition)
-										.doOnSuccess(ignore -> prepareSynchronization(nestedSynchronizationManager, status, definition))
+								return doBegin(nestedSynchronizationManager, transaction, def)
+										.doOnSuccess(ignore -> prepareSynchronization(nestedSynchronizationManager, status, def))
 										.thenReturn(status);
 							}).onErrorResume(ErrorPredicates.RUNTIME_OR_ERROR,
 									ex -> resume(nestedSynchronizationManager, null, suspendedResources.orElse(null))
@@ -147,11 +152,11 @@ else if (definition.getPropagationBehavior() == TransactionDefinition.PROPAGATIO
 			}
 			else {
 				// Create "empty" transaction: no actual transaction, but potentially synchronization.
-				if (definition.getIsolationLevel() != TransactionDefinition.ISOLATION_DEFAULT && logger.isWarnEnabled()) {
+				if (def.getIsolationLevel() != TransactionDefinition.ISOLATION_DEFAULT && logger.isWarnEnabled()) {
 					logger.warn("Custom isolation level specified but no actual transaction initiated; " +
-							"isolation level will effectively be ignored: " + definition);
+							"isolation level will effectively be ignored: " + def);
 				}
-				return Mono.just(prepareReactiveTransaction(synchronizationManager, definition, null, true, debugEnabled, null));
+				return Mono.just(prepareReactiveTransaction(synchronizationManager, def, null, true, debugEnabled, null));
 			}
 		});
 	}

spring-tx/src/main/java/org/springframework/transaction/reactive/TransactionalOperator.java

@@ -46,20 +46,6 @@
  */
 public interface TransactionalOperator {
 
-	/**
-	 * Create a new {@link TransactionalOperator} using {@link ReactiveTransactionManager}
-	 * and {@link TransactionDefinition}.
-	 * @param transactionManager the transaction management strategy to be used
-	 * @param transactionDefinition the transaction definition to apply
-	 * @return the transactional operator
-	 */
-	static TransactionalOperator create(
-			ReactiveTransactionManager transactionManager, TransactionDefinition transactionDefinition){
-
-		return new TransactionalOperatorImpl(transactionManager, transactionDefinition);
-	}
-
-
 	/**
 	 * Wrap the functional sequence specified by the given Flux within a transaction.
 	 * @param flux the Flux that should be executed within the transaction
@@ -95,4 +81,30 @@ default <T> Mono<T> transactional(Mono<T> mono) {
 	 */
 	<T> Flux<T> execute(TransactionCallback<T> action) throws TransactionException;
 
+
+	// Static builder methods
+
+	/**
+	 * Create a new {@link TransactionalOperator} using {@link ReactiveTransactionManager},
+	 * using a default transaction.
+	 * @param transactionManager the transaction management strategy to be used
+	 * @return the transactional operator
+	 */
+	static TransactionalOperator create(ReactiveTransactionManager transactionManager){
+		return create(transactionManager, TransactionDefinition.withDefaults());
+	}
+
+	/**
+	 * Create a new {@link TransactionalOperator} using {@link ReactiveTransactionManager}
+	 * and {@link TransactionDefinition}.
+	 * @param transactionManager the transaction management strategy to be used
+	 * @param transactionDefinition the transaction definition to apply
+	 * @return the transactional operator
+	 */
+	static TransactionalOperator create(
+			ReactiveTransactionManager transactionManager, TransactionDefinition transactionDefinition){
+
+		return new TransactionalOperatorImpl(transactionManager, transactionDefinition);
+	}
+
 }