Interface Stage.Session

  • All Superinterfaces:
    Stage.Closeable
    Enclosing interface:
    Stage

    public static interface Stage.Session
    extends Stage.Closeable
    A non-blocking counterpart to the Hibernate Session interface, allowing a reactive style of interaction with the database.

    The semantics of operations on this interface are identical to the semantics of the similarly-named operations of Session, except that the operations are performed asynchronously, returning a CompletionStage without blocking the calling thread.

    Entities associated with an Session do not support transparent lazy association fetching. Instead, fetch(Object) should be used to explicitly request asynchronous fetching of an association, or the association should be fetched eagerly when the entity is first retrieved, for example, by:

    See Also:
    Session
    • Method Detail

      • find

        <T> CompletionStage<T> find​(Class<T> entityClass,
                                    Object id)
        Asynchronously return the persistent instance of the given entity class with the given identifier, or null if there is no such persistent instance. If the instance is already associated with the session, return the associated instance. This method never returns an uninitialized instance.
         session.find(Book.class, id).thenAccept(book -> print(book.getTitle()));
         
        Parameters:
        entityClass - The entity type
        id - an identifier
        Returns:
        a persistent instance or null via a CompletionStage
        See Also:
        EntityManager.find(Class, Object)
      • find

        default <T> CompletionStage<T> find​(Class<T> entityClass,
                                            Object id,
                                            jakarta.persistence.LockModeType lockModeType)
        Asynchronously return the persistent instance of the given entity class with the given identifier, requesting the given LockModeType.
        Parameters:
        entityClass - The entity type
        id - an identifier
        lockModeType - the requested LockModeType
        Returns:
        a persistent instance or null via a CompletionStage
        See Also:
        find(Class,Object), this discussion of lock modes
      • find

        <T> CompletionStage<T> find​(jakarta.persistence.EntityGraph<T> entityGraph,
                                    Object id)
        Asynchronously return the persistent instance with the given identifier of an entity class, using the given EntityGraph as a fetch plan.
        Parameters:
        entityGraph - an EntityGraph specifying the entity and associations to be fetched
        id - an identifier
        See Also:
        find(Class,Object)
      • find

        <T> CompletionStage<List<T>> find​(Class<T> entityClass,
                                          Object... ids)
        Asynchronously return the persistent instances of the given entity class with the given identifiers, or null if there is no such persistent instance.
        Parameters:
        entityClass - The entity type
        ids - the identifiers
        Returns:
        a list of persistent instances and nulls via a CompletionStage
      • find

        @Incubating
        <T> CompletionStage<T> find​(Class<T> entityClass,
                                    Identifier<T> naturalId)
        Asynchronously return the persistent instance of the given entity class with the given natural identifiers, or null if there is no such persistent instance.
        Parameters:
        entityClass - The entity type
        naturalId - the natural identifier
        Returns:
        a persistent instance or null via a CompletionStage
      • getReference

        <T> T getReference​(Class<T> entityClass,
                           Object id)
        Return the persistent instance of the given entity class with the given identifier, assuming that the instance exists. This method never results in access to the underlying data store, and thus might return a proxy that must be initialized explicitly using fetch(Object).

        You should not use this method to determine if an instance exists (use find(java.lang.Class<T>, java.lang.Object) instead). Use this only to retrieve an instance which you safely assume exists, where non-existence would be an actual error.

        Parameters:
        entityClass - a persistent class
        id - a valid identifier of an existing persistent instance of the class
        Returns:
        the persistent instance or proxy
        See Also:
        EntityManager.getReference(Class, Object)
      • getReference

        <T> T getReference​(T entity)
        Return the persistent instance with the same identity as the given instance, which might be detached, assuming that the instance is still persistent in the database. This method never results in access to the underlying data store, and thus might return a proxy that must be initialized explicitly using fetch(Object).
        Parameters:
        entity - a detached persistent instance
        Returns:
        the persistent instance or proxy
      • persist

        CompletionStage<Void> persist​(Object entity)
        Asynchronously persist the given transient instance, first assigning a generated identifier. (Or using the current value of the identifier property if the entity has assigned identifiers.)

        This operation cascades to associated instances if the association is mapped with CascadeType.PERSIST.

         session.persist(newBook).thenAccept(v -> session.flush());
         
        Parameters:
        entity - a transient instance of a persistent class
        See Also:
        EntityManager.persist(Object)
      • remove

        CompletionStage<Void> remove​(Object entity)
        Asynchronously remove a persistent instance from the datastore. The argument may be an instance associated with the receiving session or a transient instance with an identifier associated with existing persistent state.

        This operation cascades to associated instances if the association is mapped with CascadeType.REMOVE.

         session.delete(book).thenAccept(v -> session.flush());
         
        Parameters:
        entity - the managed persistent instance to be removed
        Throws:
        IllegalArgumentException - if the given instance is not managed
        See Also:
        EntityManager.remove(Object)
      • merge

        <T> CompletionStage<T> merge​(T entity)
        Copy the state of the given object onto the persistent instance with the same identifier. If there is no such persistent instance currently associated with the session, it will be loaded. Return the persistent instance. Or, if the given instance is transient, save a copy of it and return the copy as a newly persistent instance. The given instance does not become associated with the session.

        This operation cascades to associated instances if the association is mapped with CascadeType.MERGE.

        Parameters:
        entity - a detached instance with state to be copied
        Returns:
        an updated persistent instance
        See Also:
        EntityManager.merge(Object)
      • refresh

        CompletionStage<Void> refresh​(Object entity)
        Re-read the state of the given instance from the underlying database. It is inadvisable to use this to implement long-running sessions that span many business tasks. This method is, however, useful in certain special circumstances, for example:
        • where a database trigger alters the object state after insert or update, or
        • after executing direct native SQL in the same session.
        Parameters:
        entity - a managed persistent instance
        Throws:
        IllegalArgumentException - if the given instance is not managed
        See Also:
        EntityManager.refresh(Object)
      • refresh

        CompletionStage<Void> refresh​(Object entity,
                                      LockMode lockMode)
        Re-read the state of the given instance from the underlying database, requesting the given LockMode.
        Parameters:
        entity - a managed persistent entity instance
        lockMode - the requested lock mode
        See Also:
        refresh(Object)
      • refresh

        default CompletionStage<Void> refresh​(Object entity,
                                              jakarta.persistence.LockModeType lockModeType)
        Re-read the state of the given instance from the underlying database, requesting the given LockModeType.
        Parameters:
        entity - a managed persistent entity instance
        lockModeType - the requested lock mode
        See Also:
        refresh(Object)
      • lock

        default CompletionStage<Void> lock​(Object entity,
                                           jakarta.persistence.LockModeType lockModeType)
        Obtain the specified lock level upon the given object. For example, this operation may be used to:
        • perform a version check with LockModeType.PESSIMISTIC_READ,
        • upgrade to a pessimistic lock with LockModeType.PESSIMISTIC_WRITE,
        • force a version increment with LockModeType.PESSIMISTIC_FORCE_INCREMENT,
        • schedule a version check just before the end of the transaction with LockModeType.OPTIMISTIC, or
        • schedule a version increment just before the end of the transaction with LockModeType.OPTIMISTIC_FORCE_INCREMENT.
        This operation cascades to associated instances if the association is mapped with CascadeType.LOCK.
        Parameters:
        entity - a managed persistent instance
        lockModeType - the lock level
        Throws:
        IllegalArgumentException - if the given instance is not managed
      • flush

        CompletionStage<Void> flush()
        Force this session to flush asynchronously. Must be called at the end of a unit of work, before committing the transaction and closing the session. Flushing is the process of synchronizing the underlying persistent store with state held in memory.
         session.flush().thenAccept(v -> print("done saving changes"));
         
        See Also:
        EntityManager.flush()
      • fetch

        <T> CompletionStage<T> fetch​(T association)
        Asynchronously fetch an association that's configured for lazy loading.

         session.fetch(author.getBook()).thenAccept(book -> print(book.getTitle()))
         

        It can also initialize proxys. For example:

         session.fetch(session.getReference(Author.class, authorId))
         

        Parameters:
        association - a lazy-loaded association, or a proxy
        Returns:
        the fetched association, via a CompletionStage
        See Also:
        Stage.fetch(Object), getReference(Class, Object), Hibernate.initialize(Object)
      • fetch

        <E,​T> CompletionStage<T> fetch​(E entity,
                                             jakarta.persistence.metamodel.Attribute<E,​T> field)
        Fetch a lazy property of the given entity, identified by a JPA attribute metamodel. Note that this feature is only supported in conjunction with the Hibernate bytecode enhancer.
         session.fetch(book, Book_.isbn).thenAccept(isbn -> print(isbn))
         
      • unproxy

        <T> CompletionStage<T> unproxy​(T association)
        Asynchronously fetch an association that's configured for lazy loading, and unwrap the underlying entity implementation from any proxy.
         session.unproxy(author.getBook()).thenAccept(book -> print(book.getTitle()));
         
        Parameters:
        association - a lazy-loaded association
        Returns:
        the fetched association, via a CompletionStage
        See Also:
        Hibernate.unproxy(Object)
      • getLockMode

        LockMode getLockMode​(Object entity)
        Determine the current lock mode of the given entity.
      • contains

        boolean contains​(Object entity)
        Determine if the given instance belongs to this persistence context.
      • createSelectionQuery

        <R> Stage.SelectionQuery<R> createSelectionQuery​(String queryString,
                                                         Class<R> resultType)
        Create an instance of Stage.SelectionQuery for the given HQL/JPQL query string.
        Parameters:
        queryString - The HQL/JPQL query
        Returns:
        The Stage.SelectionQuery instance for manipulation and execution
        See Also:
        EntityManager.createQuery(String, Class)
      • createMutationQuery

        Stage.MutationQuery createMutationQuery​(String queryString)
        Create an instance of Stage.MutationQuery for the given HQL/JPQL update or delete statement.
        Parameters:
        queryString - The HQL/JPQL query, update or delete statement
        Returns:
        The Stage.MutationQuery instance for manipulation and execution
        See Also:
        EntityManager.createQuery(String)
      • createQuery

        <R> Stage.SelectionQuery<R> createQuery​(String queryString,
                                                Class<R> resultType)
        Create an instance of Stage.SelectionQuery for the given HQL/JPQL query string and query result type.
        Parameters:
        queryString - The HQL/JPQL query
        resultType - the Java type returned in each row of query results
        Returns:
        The Stage.Query instance for manipulation and execution
        See Also:
        EntityManager.createQuery(String, Class)
      • createQuery

        <R> Stage.MutationQuery createQuery​(jakarta.persistence.criteria.CriteriaUpdate<R> criteriaUpdate)
        Create an instance of Stage.MutationQuery for the given criteria update.
        Parameters:
        criteriaUpdate - The CriteriaUpdate
        Returns:
        The Stage.MutationQuery instance for manipulation and execution
      • createQuery

        <R> Stage.MutationQuery createQuery​(jakarta.persistence.criteria.CriteriaDelete<R> criteriaDelete)
        Create an instance of Stage.MutationQuery for the given criteria delete.
        Parameters:
        criteriaDelete - The CriteriaDelete
        Returns:
        The Stage.MutationQuery instance for manipulation and execution
      • createNamedQuery

        <R> Stage.Query<R> createNamedQuery​(String queryName)
        Create an instance of Stage.Query for the named query.
        Parameters:
        queryName - The name of the query
        Returns:
        The Stage.Query instance for manipulation and execution
        See Also:
        EntityManager.createQuery(String)
      • createNamedQuery

        <R> Stage.SelectionQuery<R> createNamedQuery​(String queryName,
                                                     Class<R> resultType)
        Create an instance of Stage.SelectionQuery for the named query.
        Parameters:
        queryName - The name of the query
        resultType - the Java type returned in each row of query results
        Returns:
        The Stage.SelectionQuery instance for manipulation and execution
        See Also:
        EntityManager.createQuery(String, Class)
      • createNativeQuery

        <R> Stage.SelectionQuery<R> createNativeQuery​(String queryString,
                                                      Class<R> resultType)
        Create an instance of Stage.Query for the given SQL query string, using the given resultType to interpret the results.
        • If the given result type is Object, or a built-in type such as String or Integer, the result set must have a single column, which will be returned as a scalar.
        • If the given result type is Object[], then the result set must have multiple columns, which will be returned as elements of arrays of type Object[].
        • Otherwise, the given result type must be an entity class, in which case the result set column aliases must map to the fields of the entity, and the query will return instances of the entity.
        Parameters:
        queryString - The SQL query
        resultType - the Java type returned in each row of query results
        Returns:
        The Stage.SelectionQuery instance for manipulation and execution
        See Also:
        EntityManager.createNativeQuery(String, Class)
      • createNativeQuery

        <R> Stage.SelectionQuery<R> createNativeQuery​(String queryString,
                                                      Class<R> resultType,
                                                      AffectedEntities affectedEntities)
        Create an instance of Stage.SelectionQuery for the given SQL query string, using the given resultType to interpret the results.
        • If the given result type is Object, or a built-in type such as String or Integer, the result set must have a single column, which will be returned as a scalar.
        • If the given result type is Object[], then the result set must have multiple columns, which will be returned as elements of arrays of type Object[].
        • Otherwise, the given result type must be an entity class, in which case the result set column aliases must map to the fields of the entity, and the query will return instances of the entity.
        Any affected entities are synchronized with the database before execution of the query.
        Parameters:
        queryString - The SQL query
        resultType - the Java type returned in each row of query results
        affectedEntities - The entities which are affected by the query
        Returns:
        The Stage.Query instance for manipulation and execution
        See Also:
        EntityManager.createNativeQuery(String, Class)
      • createNativeQuery

        <R> Stage.Query<R> createNativeQuery​(String queryString)
        Create an instance of Stage.Query for the given SQL query string, or SQL update, insert, or delete statement. In the case of an update, insert, or delete, the returned Stage.Query must be executed using Stage.MutationQuery.executeUpdate() which returns an affected row count. In the case of a query:
        • If the result set has a single column, the results will be returned as scalars.
        • Otherwise, if the result set has multiple columns, the results will be returned as elements of arrays of type Object[].
        Parameters:
        queryString - The SQL select, update, insert, or delete statement
      • createNativeQuery

        <R> Stage.Query<R> createNativeQuery​(String queryString,
                                             AffectedEntities affectedEntities)
        Create an instance of Stage.Query for the given SQL query string, or SQL update, insert, or delete statement. In the case of an update, insert, or delete, the returned Stage.Query must be executed using Stage.MutationQuery.executeUpdate() which returns an affected row count. In the case of a query:
        • If the result set has a single column, the results will be returned as scalars.
        • Otherwise, if the result set has multiple columns, the results will be returned as elements of arrays of type Object[].
        Any affected entities are synchronized with the database before execution of the statement.
        Parameters:
        queryString - The SQL select, update, insert, or delete statement
        affectedEntities - The entities which are affected by the statement
      • createQuery

        <R> Stage.SelectionQuery<R> createQuery​(jakarta.persistence.criteria.CriteriaQuery<R> criteriaQuery)
        Create an instance of Stage.SelectionQuery for the given criteria query.
        Parameters:
        criteriaQuery - The CriteriaQuery
        Returns:
        The Stage.SelectionQuery instance for manipulation and execution
        See Also:
        EntityManager.createQuery(String)
      • setFlushMode

        Stage.Session setFlushMode​(FlushMode flushMode)
        Set the flush mode for this session.

        The flush mode determines the points at which the session is flushed. Flushing is the process of synchronizing the underlying persistent store with persistable state held in memory.

        For a logically "read only" session, it is reasonable to set the session's flush mode to FlushMode.MANUAL at the start of the session (in order to achieve some extra performance).

        Parameters:
        flushMode - the new flush mode
      • setFlushMode

        default Stage.Session setFlushMode​(jakarta.persistence.FlushModeType flushModeType)
        Set the flush mode for this session.

        The flush mode determines the points at which the session is flushed. Flushing is the process of synchronizing the underlying persistent store with persistable state held in memory.

        Parameters:
        flushModeType - the new flush mode
      • getFlushMode

        FlushMode getFlushMode()
        Get the current flush mode for this session.
        Returns:
        the flush mode
      • detach

        Stage.Session detach​(Object entity)
        Remove this instance from the session cache. Changes to the instance will not be synchronized with the database.

        This operation cascades to associated instances if the association is mapped with CascadeType.DETACH.

        Parameters:
        entity - The entity to evict
        Throws:
        NullPointerException - if the passed object is null
        IllegalArgumentException - if the passed object is not defined as an entity
        See Also:
        EntityManager.detach(Object)
      • clear

        Stage.Session clear()
        Completely clear the session. Detach all persistent instances and cancel all pending insertions, updates and deletions.
        See Also:
        EntityManager.clear()
      • enableFetchProfile

        Stage.Session enableFetchProfile​(String name)
        Enable a particular fetch profile on this session, or do nothing if requested fetch profile is already enabled.
        Parameters:
        name - The name of the fetch profile to be enabled.
        Throws:
        UnknownProfileException - Indicates that the given name does not match any known profile names
        See Also:
        for discussion of this feature
      • getResultSetMapping

        <T> ResultSetMapping<T> getResultSetMapping​(Class<T> resultType,
                                                    String mappingName)
        Obtain a native SQL result set mapping defined via the annotation SqlResultSetMapping.
      • getEntityGraph

        <T> jakarta.persistence.EntityGraph<T> getEntityGraph​(Class<T> rootType,
                                                              String graphName)
        Obtain a named EntityGraph
      • createEntityGraph

        <T> jakarta.persistence.EntityGraph<T> createEntityGraph​(Class<T> rootType)
        Create a new mutable EntityGraph
      • createEntityGraph

        <T> jakarta.persistence.EntityGraph<T> createEntityGraph​(Class<T> rootType,
                                                                 String graphName)
        Create a new mutable copy of a named EntityGraph
      • disableFetchProfile

        Stage.Session disableFetchProfile​(String name)
        Disable a particular fetch profile on this session, or do nothing if the requested fetch profile is not enabled.
        Parameters:
        name - The name of the fetch profile to be disabled.
        Throws:
        UnknownProfileException - Indicates that the given name does not match any known profile names
        See Also:
        for discussion of this feature
      • isFetchProfileEnabled

        boolean isFetchProfileEnabled​(String name)
        Determine if the fetch profile with the given name is enabled for this session.
        Parameters:
        name - The name of the profile to be checked.
        Returns:
        True if fetch profile is enabled; false if not.
        Throws:
        UnknownProfileException - Indicates that the given name does not match any known profile names
        See Also:
        for discussion of this feature
      • setDefaultReadOnly

        Stage.Session setDefaultReadOnly​(boolean readOnly)
        Change the default for entities and proxies loaded into this session from modifiable to read-only mode, or from modifiable to read-only mode.

        Read-only entities are not dirty-checked and snapshots of persistent state are not maintained. Read-only entities can be modified, but changes are not persisted.

        See Also:
        Session.setDefaultReadOnly(boolean)
      • isDefaultReadOnly

        boolean isDefaultReadOnly()
        Returns:
        the default read-only mode for entities and proxies loaded in this session
      • setReadOnly

        Stage.Session setReadOnly​(Object entityOrProxy,
                                  boolean readOnly)
        Set an unmodified persistent object to read-only mode, or a read-only object to modifiable mode. In read-only mode, no snapshot is maintained, the instance is never dirty checked, and changes are not persisted.
        See Also:
        Session.setReadOnly(Object, boolean)
      • setCacheMode

        Stage.Session setCacheMode​(CacheMode cacheMode)
        Set the cache mode for this session.

        The cache mode determines the manner in which this session interacts with the second level cache.

        Parameters:
        cacheMode - The new cache mode.
      • setCacheStoreMode

        default Stage.Session setCacheStoreMode​(jakarta.persistence.CacheStoreMode cacheStoreMode)
        Set the CacheStoreMode for this session.
        Parameters:
        cacheStoreMode - The new cache store mode.
      • setCacheRetrieveMode

        default Stage.Session setCacheRetrieveMode​(jakarta.persistence.CacheRetrieveMode cacheRetrieveMode)
        Set the CacheRetrieveMode for this session.
        Parameters:
        cacheRetrieveMode - The new cache retrieve mode.
      • getCacheMode

        CacheMode getCacheMode()
        Get the current cache mode.
        Returns:
        The current cache mode.
      • setBatchSize

        Stage.Session setBatchSize​(Integer batchSize)
        Set the session-level batch size, overriding the batch size set by the configuration property hibernate.jdbc.batch_size.
      • getBatchSize

        Integer getBatchSize()
        The session-level batch size, or null if it has not been overridden.
      • getFetchBatchSize

        int getFetchBatchSize()
        Get the maximum batch size for batch fetching associations by id in this session.
        Since:
        2.1
      • setFetchBatchSize

        Stage.Session setFetchBatchSize​(int batchSize)
        Set the maximum batch size for batch fetching associations by id in this session. Override the default controlled by the configuration property hibernate.default_batch_fetch_size.

        • If batchSize>1, then batch fetching is enabled.
        • If batchSize<0, the batch size is inherited from the factory-level setting.
        • Otherwise, batch fetching is disabled.
        Parameters:
        batchSize - the maximum batch size for batch fetching
        Since:
        2.1
      • isSubselectFetchingEnabled

        boolean isSubselectFetchingEnabled()
        Determine if subselect fetching is enabled in this session.
        Returns:
        true if subselect fetching is enabled
        Since:
        2.1
      • setSubselectFetchingEnabled

        Stage.Session setSubselectFetchingEnabled​(boolean enabled)
        Enable or disable subselect fetching in this session. Override the default controlled by the configuration property hibernate.use_subselect_fetch.
        Parameters:
        enabled - true to enable subselect fetching
        Since:
        2.1
      • enableFilter

        Filter enableFilter​(String filterName)
        Enable the named filter for this session.
        Parameters:
        filterName - The name of the filter to be enabled.
        Returns:
        The Filter instance representing the enabled filter.
      • disableFilter

        void disableFilter​(String filterName)
        Disable the named filter for this session.
        Parameters:
        filterName - The name of the filter to be disabled.
      • getEnabledFilter

        Filter getEnabledFilter​(String filterName)
        Retrieve a currently enabled filter by name.
        Parameters:
        filterName - The name of the filter to be retrieved.
        Returns:
        The Filter instance representing the enabled filter.
      • withTransaction

        <T> CompletionStage<T> withTransaction​(Function<Stage.Transaction,​CompletionStage<T>> work)
        Performs the given work within the scope of a database transaction, automatically flushing the session. The transaction will be rolled back if the work completes with an uncaught exception, or if Stage.Transaction.markForRollback() is called.

        The resulting Stage.Transaction object may also be obtained via currentTransaction().

      • If there is already a transaction associated with this session, the work is executed in the context of the existing transaction, and no new transaction is initiated.
      • If there is no transaction associated with this session, a new transaction is started, and the work is executed in the context of the new transaction.
Parameters:
work - a function which accepts Stage.Transaction and returns the result of the work as a CompletionStage.
See Also:
Stage.SessionFactory.withTransaction(BiFunction)