Class TransactionSynchronizationManager


  • public abstract class TransactionSynchronizationManager
    extends java.lang.Object
    Central delegate that manages resources and transaction synchronizations per thread. To be used by resource management code but not by typical application code.

    Supports one resource per key without overwriting, that is, a resource needs to be removed before a new one can be set for the same key. Supports a list of transaction synchronizations if synchronization is active.

    Resource management code should check for thread-bound resources, e.g. JDBC Connections or Hibernate Sessions, via getResource. Such code is normally not supposed to bind resources to threads, as this is the responsibility of transaction managers. A further option is to lazily bind on first use if transaction synchronization is active, for performing transactions that span an arbitrary number of resources.

    Transaction synchronization must be activated and deactivated by a transaction manager via initSynchronization() and clearSynchronization(). This is automatically supported by AbstractSynchronousTransactionManager, and thus by all standard transaction managers.

    Resource management code should only register synchronizations when this manager is active, which can be checked via isSynchronizationActive(); it should perform immediate resource cleanup else. If transaction synchronization isn't active, there is either no current transaction, or the transaction manager doesn't support transaction synchronization.

    Synchronization is for example used to always return the same resources within a JTA transaction, e.g. a JDBC Connection or a Hibernate Session for any given DataSource or SessionFactory, respectively.

    Since:
    02.06.2003
    Author:
    Juergen Hoeller
    See Also:
    isSynchronizationActive(), registerSynchronization(io.micronaut.transaction.support.TransactionSynchronization), TransactionSynchronization, AbstractSynchronousStateTransactionManager.setTransactionSynchronization(io.micronaut.transaction.support.AbstractSynchronousStateTransactionManager.Synchronization)
    • Field Detail

      • DEFAULT_STATE_KEY

        public static final java.lang.Object DEFAULT_STATE_KEY
    • Constructor Detail

      • TransactionSynchronizationManager

        public TransactionSynchronizationManager()
    • Method Detail

      • getResourceMap

        public static java.util.Map<java.lang.Object,​java.lang.Object> getResourceMap()
        Return all resources that are bound to the current thread.

        Mainly for debugging purposes. Resource managers should always invoke hasResource for a specific resource key that they are interested in.

        Returns:
        a Map with resource keys (usually the resource factory) and resource values (usually the active resource object), or an empty Map if there are currently no resources bound
        See Also:
        hasResource(java.lang.Object)
      • hasResource

        public static boolean hasResource​(java.lang.Object key)
        Check if there is a resource for the given key bound to the current thread.
        Parameters:
        key - the key to check (usually the resource factory)
        Returns:
        if there is a value bound to the current thread
        See Also:
        ResourceTransactionManager.getResourceFactory()
      • getResource

        @Nullable
        public static java.lang.Object getResource​(java.lang.Object key)
        Retrieve a resource for the given key that is bound to the current thread.
        Parameters:
        key - the key to check (usually the resource factory)
        Returns:
        a value bound to the current thread (usually the active resource object), or null if none
        See Also:
        ResourceTransactionManager.getResourceFactory()
      • getResourceOrDefault

        @NonNull
        public static <T> T getResourceOrDefault​(java.lang.Object key,
                                                 @NonNull
                                                 T defaultValue)
      • bindResource

        public static void bindResource​(java.lang.Object key,
                                        java.lang.Object value)
                                 throws java.lang.IllegalStateException
        Bind the given resource for the given key to the current thread.
        Parameters:
        key - the key to bind the value to (usually the resource factory)
        value - the value to bind (usually the active resource object)
        Throws:
        java.lang.IllegalStateException - if there is already a value bound to the thread
        See Also:
        ResourceTransactionManager.getResourceFactory()
      • rebindResource

        public static void rebindResource​(java.lang.Object key,
                                          java.lang.Object value)
                                   throws java.lang.IllegalStateException
        Throws:
        java.lang.IllegalStateException
      • unbindResource

        public static java.lang.Object unbindResource​(java.lang.Object key)
                                               throws java.lang.IllegalStateException
        Unbind a resource for the given key from the current thread.
        Parameters:
        key - the key to unbind (usually the resource factory)
        Returns:
        the previously bound value (usually the active resource object)
        Throws:
        java.lang.IllegalStateException - if there is no value bound to the thread
        See Also:
        ResourceTransactionManager.getResourceFactory()
      • unbindResourceIfPossible

        @Nullable
        public static java.lang.Object unbindResourceIfPossible​(java.lang.Object key)
        Unbind a resource for the given key from the current thread.
        Parameters:
        key - the key to unbind (usually the resource factory)
        Returns:
        the previously bound value, or null if none bound
      • bindSynchronousTransactionState

        public static void bindSynchronousTransactionState​(@NonNull
                                                           java.lang.Object key,
                                                           @NonNull
                                                           SynchronousTransactionState state)
      • unbindSynchronousTransactionState

        public static SynchronousTransactionState unbindSynchronousTransactionState​(java.lang.Object key)
                                                                             throws java.lang.IllegalStateException
        Throws:
        java.lang.IllegalStateException
      • getSynchronousTransactionState

        @Nullable
        public static SynchronousTransactionState getSynchronousTransactionState​(@NonNull
                                                                                 java.lang.Object key)
      • getRequiredSynchronousTransactionState

        @NonNull
        public static SynchronousTransactionState getRequiredSynchronousTransactionState​(@NonNull
                                                                                         java.lang.Object key)
      • initSynchronization

        @Deprecated
        public static void initSynchronization()
                                        throws java.lang.IllegalStateException
        Activate transaction synchronization for the current thread. Called by a transaction manager on transaction begin.
        Throws:
        java.lang.IllegalStateException - if synchronization is already active
      • registerSynchronization

        @Deprecated
        public static void registerSynchronization​(TransactionSynchronization synchronization)
                                            throws java.lang.IllegalStateException
        Register a new transaction synchronization for the current thread. Typically called by resource management code.

        Note that synchronizations can implement the Ordered interface. They will be executed in an order according to their order value (if any).

        Parameters:
        synchronization - the synchronization object to register
        Throws:
        java.lang.IllegalStateException - if transaction synchronization is not active
        See Also:
        Ordered
      • getSynchronizations

        @Deprecated
        public static java.util.List<TransactionSynchronization> getSynchronizations()
                                                                              throws java.lang.IllegalStateException
        Return an unmodifiable snapshot list of all registered synchronizations for the current thread.
        Returns:
        unmodifiable List of TransactionSynchronization instances
        Throws:
        java.lang.IllegalStateException - if synchronization is not active
        See Also:
        TransactionSynchronization
      • clearSynchronization

        @Deprecated
        public static void clearSynchronization()
                                         throws java.lang.IllegalStateException
        Deactivate transaction synchronization for the current thread. Called by the transaction manager on transaction cleanup.
        Throws:
        java.lang.IllegalStateException - if synchronization is not active
      • setCurrentTransactionName

        @Deprecated
        public static void setCurrentTransactionName​(@Nullable
                                                     java.lang.String name)
        Expose the name of the current transaction, if any. Called by the transaction manager on transaction begin and on cleanup.
        Parameters:
        name - the name of the transaction, or null to reset it
        See Also:
        TransactionDefinition.getName()
      • getCurrentTransactionName

        @Deprecated
        @Nullable
        public static java.lang.String getCurrentTransactionName()
        Return the name of the current transaction, or null if none set. To be called by resource management code for optimizations per use case, for example to optimize fetch strategies for specific named transactions.
        Returns:
        The current transaction name
        See Also:
        TransactionDefinition.getName()
      • setCurrentTransactionReadOnly

        @Deprecated
        public static void setCurrentTransactionReadOnly​(boolean readOnly)
        Expose a read-only flag for the current transaction. Called by the transaction manager on transaction begin and on cleanup.
        Parameters:
        readOnly - true to mark the current transaction as read-only; false to reset such a read-only marker
        See Also:
        TransactionDefinition.isReadOnly()
      • isCurrentTransactionReadOnly

        @Deprecated
        public static boolean isCurrentTransactionReadOnly()
        Return whether the current transaction is marked as read-only. To be called by resource management code when preparing a newly created resource (for example, a Hibernate Session).

        Note that transaction synchronizations receive the read-only flag as argument for the beforeCommit callback, to be able to suppress change detection on commit. The present method is meant to be used for earlier read-only checks, for example to set the flush mode of a Hibernate Session to "FlushMode.NEVER" upfront.

        Returns:
        Whether the transaction is read only
        See Also:
        TransactionDefinition.isReadOnly(), TransactionSynchronization.beforeCommit(boolean)
      • setActualTransactionActive

        @Deprecated
        public static void setActualTransactionActive​(boolean active)
        Expose whether there currently is an actual transaction active. Called by the transaction manager on transaction begin and on cleanup.
        Parameters:
        active - true to mark the current thread as being associated with an actual transaction; false to reset that marker
      • isActualTransactionActive

        @Deprecated
        public static boolean isActualTransactionActive()
        Return whether there currently is an actual transaction active. This indicates whether the current thread is associated with an actual transaction rather than just with active transaction synchronization.

        To be called by resource management code that wants to discriminate between active transaction synchronization (with or without backing resource transaction; also on PROPAGATION_SUPPORTS) and an actual transaction being active (with backing resource transaction; on PROPAGATION_REQUIRED, PROPAGATION_REQUIRES_NEW, etc).

        Returns:
        Whether a transaction is active
        See Also:
        isSynchronizationActive()
      • withState

        @Internal
        public static <T> T withState​(@Nullable
                                      TransactionSynchronizationManager.TransactionSynchronizationState state,
                                      java.util.function.Supplier<T> supplier)
        Execute provided supplier with setup state in the thread-local. Afterwards update the state with the modifications done to it.
        Type Parameters:
        T - The supplied type
        Parameters:
        state - The state
        supplier - The supplier to be executed
        Returns:
        The suppler return value
        Since:
        3.4.0
      • decorateCompletionStage

        @Internal
        public static <T> java.util.concurrent.CompletionStage<T> decorateCompletionStage​(@Nullable
                                                                                          TransactionSynchronizationManager.TransactionSynchronizationState state,
                                                                                          java.util.function.Supplier<java.util.concurrent.CompletionStage<T>> supplier)
        Decorate completion stage supplier with the transaction state.
        Type Parameters:
        T - The supplied type
        Parameters:
        state - The state
        supplier - The supplier to be executed
        Returns:
        The suppler return value
        Since:
        3.5.0
      • decorateToPropagateState

        @Internal
        public static <T> java.util.function.Supplier<T> decorateToPropagateState​(java.util.function.Supplier<T> supplier)
        Decorate the supplier with possible propagated state in thread-local.

        It's used to propagated TX state down to the async functions.

        Type Parameters:
        T - The supplied type
        Parameters:
        supplier - The supplier to be decorated
        Returns:
        The decorated supplier
        Since:
        3.4.0