Class AbstractDelegatingCacheStream<R>

    • Field Detail

      • underlyingStream

        protected CacheStream<?> underlyingStream
    • Constructor Detail

      • AbstractDelegatingCacheStream

        public AbstractDelegatingCacheStream​(CacheStream<R> stream)
    • Method Detail

      • filterKeySegments

        public AbstractDelegatingCacheStream<R> filterKeySegments​(Set<Integer> segments)
        Description copied from interface: CacheStream
        Filters which entries are returned by what segment they are present in. This method can be substantially more efficient than using a regular CacheStream.filter(Predicate) method as this can control what nodes are asked for data and what entries are read from the underlying CacheStore if present.
        Specified by:
        filterKeySegments in interface BaseCacheStream<R,​Stream<R>>
        Specified by:
        filterKeySegments in interface CacheStream<R>
        Parameters:
        segments - The segments to use for this stream operation. Any segments not in this set will be ignored.
        Returns:
        a stream with the segments filtered.
      • filterKeySegments

        public AbstractDelegatingCacheStream<R> filterKeySegments​(IntSet segments)
        Description copied from interface: CacheStream
        Filters which entries are returned by what segment they are present in. This method can be substantially more efficient than using a regular CacheStream.filter(Predicate) method as this can control what nodes are asked for data and what entries are read from the underlying CacheStore if present.
        Specified by:
        filterKeySegments in interface BaseCacheStream<R,​Stream<R>>
        Specified by:
        filterKeySegments in interface CacheStream<R>
        Parameters:
        segments - The segments to use for this stream operation. Any segments not in this set will be ignored.
        Returns:
        a stream with the segments filtered.
      • segmentCompletionListener

        public AbstractDelegatingCacheStream<R> segmentCompletionListener​(BaseCacheStream.SegmentCompletionListener listener)
        Description copied from interface: CacheStream
        Allows registration of a segment completion listener that is notified when a segment has completed processing. If the terminal operator has a short circuit this listener may never be called.

        This method is designed for the sole purpose of use with the CacheStream.iterator() to allow for a user to track completion of segments as they are returned from the iterator. Behavior of other methods is not specified. Please see CacheStream.iterator() for more information.

        Multiple listeners may be registered upon multiple invocations of this method. The ordering of notified listeners is not specified.

        This is only used if this stream did not invoke BaseCacheStream.disableRehashAware() and has no flat map based operations. If this is done no segments will be notified.

        Specified by:
        segmentCompletionListener in interface BaseCacheStream<R,​Stream<R>>
        Specified by:
        segmentCompletionListener in interface CacheStream<R>
        Parameters:
        listener - The listener that will be called back as segments are completed.
        Returns:
        a stream with the listener registered.
      • disableRehashAware

        public AbstractDelegatingCacheStream<R> disableRehashAware()
        Description copied from interface: CacheStream
        Disables tracking of rehash events that could occur to the underlying cache. If a rehash event occurs while a terminal operation is being performed it is possible for some values that are in the cache to not be found. Note that you will never have an entry duplicated when rehash awareness is disabled, only lost values.

        Most terminal operations will run faster with rehash awareness disabled even without a rehash occuring. However if a rehash occurs with this disabled be prepared to possibly receive only a subset of values.

        Specified by:
        disableRehashAware in interface BaseCacheStream<R,​Stream<R>>
        Specified by:
        disableRehashAware in interface CacheStream<R>
        Returns:
        a stream with rehash awareness disabled.
      • timeout

        public AbstractDelegatingCacheStream<R> timeout​(long timeout,
                                                        TimeUnit unit)
        Description copied from interface: CacheStream
        Sets a given time to wait for a remote operation to respond by. This timeout does nothing if the terminal operation does not go remote.

        If a timeout does occur then a TimeoutException is thrown from the terminal operation invoking thread or on the next call to the Iterator or Spliterator.

        Note that if a rehash occurs this timeout value is reset for the subsequent retry if rehash aware is enabled.

        Specified by:
        timeout in interface BaseCacheStream<R,​Stream<R>>
        Specified by:
        timeout in interface CacheStream<R>
        Parameters:
        timeout - the maximum time to wait
        unit - the time unit of the timeout argument
        Returns:
        a stream with the timeout set
      • forEach

        public void forEach​(Consumer<? super R> action)
        Description copied from interface: CacheStream

        This operation is performed remotely on the node that is the primary owner for the key tied to the entry(s) in this stream.

        NOTE: This method while being rehash aware has the lowest consistency of all of the operators. This operation will be performed on every entry at least once in the cluster, as long as the originator doesn't go down while it is being performed. This is due to how the distributed action is performed. Essentially the CacheStream.distributedBatchSize(int) value controls how many elements are processed per node at a time when rehash is enabled. After those are complete the keys are sent to the originator to confirm that those were processed. If that node goes down during/before the response those keys will be processed a second time.

        It is possible to have the cache local to each node injected into this instance if the provided Consumer also implements the CacheAware interface. This method will be invoked before the consumer accept() method is invoked.

        This method is ran distributed by default with a distributed backing cache. However if you wish for this operation to run locally you can use the stream().iterator().forEachRemaining(action) for a single threaded variant. If you wish to have a parallel variant you can use StreamSupport.stream(Spliterator, boolean) passing in the spliterator from the stream. In either case remember you must close the stream after you are done processing the iterator or spliterator..

        Specified by:
        forEach in interface CacheStream<R>
        Specified by:
        forEach in interface Stream<R>
        Parameters:
        action - consumer to be ran for each element in the stream
      • forEach

        public <K,​V> void forEach​(BiConsumer<Cache<K,​V>,​? super R> action)
        Description copied from interface: CacheStream
        Same as CacheStream.forEach(Consumer) except that it takes a BiConsumer that provides access to the underlying Cache that is backing this stream.

        Note that the CacheAware interface is not supported for injection using this method as the cache is provided in the consumer directly.

        Specified by:
        forEach in interface CacheStream<R>
        Type Parameters:
        K - key type of the cache
        V - value type of the cache
        Parameters:
        action - consumer to be ran for each element in the stream
      • collect

        public <R1> R1 collect​(Supplier<R1> supplier,
                               BiConsumer<R1,​? super R> accumulator,
                               BiConsumer<R1,​R1> combiner)
        Description copied from interface: CacheStream

        Note: The accumulator and combiner are applied on each node until all the local stream's values are reduced into a single object. Because of marshalling limitations, the final result of the collector on remote nodes is limited to a size of 2GB. If you need to process more than 2GB of data, you must force the collector to run on the originator with CacheStream.spliterator():

         StreamSupport.stream(stream.filter(entry -> ...)
                                    .map(entry -> ...)
                                    .spliterator(),
                              false)
                      .collect(Collectors.toList());
         

        Specified by:
        collect in interface CacheStream<R>
        Specified by:
        collect in interface Stream<R>
      • iterator

        public Iterator<R> iterator()
        Description copied from interface: CacheStream

        Usage of this operator requires closing this stream after you are done with the iterator. The preferred usage is to use a try with resource block on the stream.

        This method has special usage with the BaseCacheStream.SegmentCompletionListener in that as entries are retrieved from the next method it will complete segments.

        This method obeys the CacheStream.distributedBatchSize(int). Note that when using methods such as CacheStream.flatMap(Function) that you will have possibly more than 1 element mapped to a given key so this doesn't guarantee that many number of entries are returned per batch.

        Note that the Iterator.remove() method is only supported if no intermediate operations have been applied to the stream and this is not a stream created from a Cache.values() collection.

        Specified by:
        iterator in interface BaseStream<R,​Stream<R>>
        Specified by:
        iterator in interface CacheStream<R>
        Returns:
        the element iterator for this stream
      • spliterator

        public Spliterator<R> spliterator()
        Description copied from interface: CacheStream

        Usage of this operator requires closing this stream after you are done with the spliterator. The preferred usage is to use a try with resource block on the stream.

        Specified by:
        spliterator in interface BaseStream<R,​Stream<R>>
        Specified by:
        spliterator in interface CacheStream<R>
        Returns:
        the element spliterator for this stream
      • sorted

        public CacheStream<R> sorted()
        Description copied from interface: CacheStream

        This operation is performed entirely on the local node irrespective of the backing cache. This operation will act as an intermediate iterator operation requiring data be brought locally for proper behavior. Beware this means it will require having all entries of this cache into memory at one time. This is described in more detail at CacheStream

        Any subsequent intermediate operations and the terminal operation are also performed locally.

        Specified by:
        sorted in interface CacheStream<R>
        Specified by:
        sorted in interface Stream<R>
        Returns:
        the new stream
      • sorted

        public CacheStream<R> sorted​(Comparator<? super R> comparator)
        Description copied from interface: CacheStream

        This operation is performed entirely on the local node irrespective of the backing cache. This operation will act as an intermediate iterator operation requiring data be brought locally for proper behavior. Beware this means it will require having all entries of this cache into memory at one time. This is described in more detail at CacheStream

        Any subsequent intermediate operations and the terminal operation are then performed locally.

        Specified by:
        sorted in interface CacheStream<R>
        Specified by:
        sorted in interface Stream<R>
        Parameters:
        comparator - the comparator to be used for sorting the elements
        Returns:
        the new stream
      • limit

        public CacheStream<R> limit​(long maxSize)
        Description copied from interface: CacheStream

        This intermediate operation will be performed both remotely and locally to reduce how many elements are sent back from each node. More specifically this operation is applied remotely on each node to only return up to the maxSize value and then the aggregated results are limited once again on the local node.

        This operation will act as an intermediate iterator operation requiring data be brought locally for proper behavior. This is described in more detail in the CacheStream documentation

        Any subsequent intermediate operations and the terminal operation are then performed locally.

        Specified by:
        limit in interface CacheStream<R>
        Specified by:
        limit in interface Stream<R>
        Parameters:
        maxSize - how many elements to limit this stream to.
        Returns:
        the new stream
      • skip

        public CacheStream<R> skip​(long n)
        Description copied from interface: CacheStream

        This operation is performed entirely on the local node irrespective of the backing cache. This operation will act as an intermediate iterator operation requiring data be brought locally for proper behavior. This is described in more detail in the CacheStream documentation

        Depending on the terminal operator this may or may not require all entries or a subset after skip is applied to be in memory all at once.

        Any subsequent intermediate operations and the terminal operation are then performed locally.

        Specified by:
        skip in interface CacheStream<R>
        Specified by:
        skip in interface Stream<R>
        Parameters:
        n - how many elements to skip from this stream
        Returns:
        the new stream
      • map

        public <R1> CacheStream<R1> map​(Function<? super R,​? extends R1> mapper)
        Description copied from interface: CacheStream

        Just like in the cache, null values are not supported.

        Specified by:
        map in interface CacheStream<R>
        Specified by:
        map in interface Stream<R>
        Returns:
        the new cache stream
      • distinct

        public CacheStream<R> distinct()
        Description copied from interface: CacheStream

        This operation will be invoked both remotely and locally when used with a distributed cache backing this stream. This operation will act as an intermediate iterator operation requiring data be brought locally for proper behavior. This is described in more detail in the CacheStream documentation

        This intermediate iterator operation will be performed locally and remotely requiring possibly a subset of all elements to be in memory

        Any subsequent intermediate operations and the terminal operation are then performed locally.

        Specified by:
        distinct in interface CacheStream<R>
        Specified by:
        distinct in interface Stream<R>
        Returns:
        the new stream
      • collect

        public <R1,​A> R1 collect​(Collector<? super R,​A,​R1> collector)
        Description copied from interface: CacheStream

        Note when using a distributed backing cache for this stream the collector must be marshallable. This prevents the usage of Collectors class. However you can use the CacheCollectors static factory methods to create a serializable wrapper, which then creates the actual collector lazily after being deserialized. This is useful to use any method from the Collectors class as you would normally. Alternatively, you can call CacheStream.collect(SerializableSupplier) too.

        Note: The collector is applied on each node until all the local stream's values are reduced into a single object. Because of marshalling limitations, the final result of the collector on remote nodes is limited to a size of 2GB. If you need to process more than 2GB of data, you must force the collector to run on the originator with CacheStream.spliterator():

         StreamSupport.stream(stream.filter(entry -> ...)
                                    .map(entry -> ...)
                                    .spliterator(),
                              false)
                      .collect(Collectors.toList());
         

        Specified by:
        collect in interface CacheStream<R>
        Specified by:
        collect in interface Stream<R>
        Type Parameters:
        R1 - collected type
        A - intermediate collected type if applicable
        Returns:
        the collected value
        See Also:
        CacheCollectors
      • count

        public long count()
        Specified by:
        count in interface Stream<R>