Package one.microstream.persistence.binary.types

Class BinaryStorer.Default

    • Constructor Detail

      • Default

        public Default()

    • Method Detail

      • apply

        public <T> long apply​(T instance)
        Description copied from interface: PersistenceStoreHandler
        The "natural" way of handling an instance as defined by the implementation.
        Specified by:
        apply in interface PersistenceFunction
        Specified by:
        apply in interface PersistenceStoreHandler
        Parameters:
        instance - the instance to which the function shall be applied.
        Returns:
        the object ID (OID) that is associated with the passed instance.

      • applyEager

        public final <T> long applyEager​(T instance)
        Description copied from interface: PersistenceStoreHandler
        A way to signal to the implementation that the passed instance is supposed to be handled eagerly, meaning it shall be handled even if the handling implementation does not deem it necessary.
        This is needed, for example, to store composition pattern instances without breaking OOP encapsulation concepts.
        Specified by:
        applyEager in interface PersistenceStoreHandler

      • initialize

        public BinaryStorer initialize​(long initialCapacity)
        Description copied from interface: PersistenceStorer
        Ensures the storer instance is initialized, i.e. ready to perform storing. If the storer instance needs to be initialized as a consequence of this call, the passed initialCapacityis considered as an estimate for the number of unique instances to be handled until the next commit. This method is idempotent, meaning if this instance is already initialized, the passed value might not have any effect. For a forced (re)initialization, see Storer.reinitialize(long).
        Specified by:
        initialize in interface BinaryStorer
        Specified by:
        initialize in interface PersistenceStorer
        Specified by:
        initialize in interface Storer
        Returns:
        this.

      • currentCapacity

        public final long currentCapacity()
        Description copied from interface: Storer
        Returns the internal state's value significant for its capacity of unique instances. Note that the exact meaning of this value is implementation dependant, e.g. it might just be a hash table's length, while the actual amount of unique instances that can be handled by that hash table might be much higher (infinite).
        Specified by:
        currentCapacity in interface BinaryStorer
        Specified by:
        currentCapacity in interface Storer
        Returns:
        the current implementation-specific "capacity" value.

      • maximumCapacity

        public final long maximumCapacity()
        Description copied from interface: Storer
        The maximum value that Storer.currentCapacity() can reach. For more explanation on the exact meaning of the capacity, see there.
        Specified by:
        maximumCapacity in interface BinaryStorer
        Specified by:
        maximumCapacity in interface Storer
        Returns:
        the maximum of the implementation-specific "capacity" value.

      • ensureCapacity

        public PersistenceStorer ensureCapacity​(long desiredCapacity)
        Description copied from interface: PersistenceStorer
        Ensures that the instance's internal state is prepared for handling an amount of unique instance equal to the passed value. Note that is explicitly does not have to mean that the instance's internal state actually reserves as much space, only makes a best effort to prepare for that amount. Example: an internal hash table's hash length might still remain at 2^30, despite the passed value being much higher.
        Specified by:
        ensureCapacity in interface BinaryStorer
        Specified by:
        ensureCapacity in interface PersistenceStorer
        Specified by:
        ensureCapacity in interface Storer
        Parameters:
        desiredCapacity - the amount of unique instances that this instance shall prepare to handle.
        Returns:
        this

      • isInitialized

        public final boolean isInitialized()
        Description copied from interface: Storer
        Returns whether this Storer instance has been initialized.

        That being initialized means exactely depends on the implementation. The general contract means to bring the instance's internal data into a state with which the instance can be used to perform its actual tasks.

        Specified by:
        isInitialized in interface Storer
        Returns:
        whether this Storer instance has been initialized.

      • size

        public final long size()
        Specified by:
        size in interface Storer
        Returns:
        the amount of unique instances / references that have already been registered by thisStorer instance. This includes both instances encountered during the data collection process and instances that have explicitely been registered to be skipped.
        See Also:
        Storer.skip(Object), Storer.skipMapped(Object,long)

      • store

        public final long store​(Object root)
        Description copied from interface: PersistenceStoring
        Stores the passed instance in any case and all referenced instances of persistable references recursively, but stores referenced instances only if they are newly encountered (e.g. don't have an id associated with them in the object registry, yet and are therefore required to be handled). This is useful for the common case of just storing an updated instance and potentially newly created instances along with it while skipping all existing (and normally unchanged) referenced instances.

        Specified by:
        store in interface PersistenceStoring
        Parameters:
        root - the root instance of the subgraph of required instances to be stored.
        Returns:
        the object id representing the passed instance.

      • storeAll

        public final long[] storeAll​(Object... instances)
        Description copied from interface: PersistenceStoring
        Convenience method to PersistenceStoring.store(Object) multiple instances. The passed array (maybe implicitely created by the compiler) itself is NOT stored.
        Specified by:
        storeAll in interface PersistenceStoring
        Parameters:
        instances - multiple root instances of the subgraphs of required instances to be stored.
        Returns:
        an array containing the object ids representing the passed instances.

      • storeAll

        public void storeAll​(Iterable<?> instances)
        Description copied from interface: PersistenceStoring
        Convenience method to PersistenceStoring.store(Object) all instances of an Iterable type, usually a collection.
        The passed instance itself is NOT stored.
        Note that this method does not return an array of objectIds, since the amount of instances supplied by the passed Iterable cannot be known until after all instances have been stored and the memory and performance overhead to collect them dynamically would not be worth it in most cases since the returned array is hardly ever needed. If it should be needed, the desired behavior can be easily achieved with a tiny custom-made utility method.
        Specified by:
        storeAll in interface PersistenceStoring
        Parameters:
        instances - multiple root instances of the subgraphs of required instances to be stored.

      • commit

        public final Object commit()
        Description copied from interface: Storer
        Ends the data collection process and causes all collected data to be persisted.

        This is an atomatic all-or-nothing operation: either all collected data will be persisted successfully, or non of it will be persisted. Partially persisted data will be reverted / rolled back in case of a failure.

        Specified by:
        commit in interface Storer
        Returns:
        some kind of status information, potentially null.

      • clear

        public void clear()
        Description copied from interface: Storer
        Clears all internal state regarding collected data and/or registered skips.
        Specified by:
        clear in interface Storer

      • lookupOid

        public final long lookupOid​(Object instance)

      • rebuildStoreItems

        public final void rebuildStoreItems()

      • rebuildStoreItems

        public final void rebuildStoreItems​(int newLength)

      • skipMapped

        public final boolean skipMapped​(Object instance,
                                long objectId)
        Description copied from interface: Storer
        Registers the passed instance under the passed objectId without persisting its data.

        This skip means that if the passed instance is encountered while collecting data to be persisted, its data will NOT be collected. References to the passed instance will be persisted as the passed objectId.

        Warning:
        This method can be very useful to rearrange object graphs on the persistence level, but it can also cause inconsistencies if not used perfectly correctly.
        It is strongly advised to use one of the following alternatives instead: Storer.skip(Object)Storer.skipNulled(Object)

        Specified by:
        skipMapped in interface Storer
        Parameters:
        instance - the instance / reference to be skipped.
        objectId - the objectId to be used as a reference to the skipped instance.
        Returns:
        true if the instance has been newly registered, false if it already was.
        See Also:
        Storer.skip(Object), Storer.skipNulled(Object)

      • skip

        public final boolean skip​(Object instance)
        Description copied from interface: Storer
        Registers the passed instance to be skipped from the data persisting process.

        This skip means that if the passed instance is encountered while collecting data to be persisted, its data will NOT be collected. If the instance is already registered under a certain object id at the used PersistenceObjectRegistry, then is associated object id will be used. Otherwise, the null-Id will be used, effectively "nulling out" all references to this instance on the persistent level.
        The latter behavior is exactly the same as Storer.skipNulled(Object).

        Specified by:
        skip in interface Storer
        Parameters:
        instance - the instance / reference to be skipped.
        Returns:
        true if the instance has been newly registered, false if it already was.
        See Also:
        Storer.skipNulled(Object), Storer.skipMapped(Object,long)

      • skipNulled

        public final boolean skipNulled​(Object instance)
        Description copied from interface: Storer
        Registers the passed instance to be skipped from the data persisting process.

        This skip means that if the passed instance is encountered while collecting data to be persisted, its data will NOT be collected. References to this instance will always be persisted as null, no matter if the instance is already registered for a certain object id at the used PersistenceObjectRegistryor not.
        To make the skipping consider existing object id registrations, use Storer.skip(Object).

        Specified by:
        skipNulled in interface Storer
        Parameters:
        instance - the instance / reference to be skipped by using .
        Returns:
        true if the instance has been newly registered, false if it already was.
        See Also:
        Storer.skip(Object), Storer.skipMapped(Object,long)