Examples with Spliterator java.util.Spliterator used on opensource projects

Example 6 with Spliterator

use of java.util.Spliterator in project jdk8u_jdk by JetBrains.

the class StreamSpliteratorTest method testLongSplitting.

//
public void testLongSplitting() {
    List<Consumer<LongStream>> terminalOps = Arrays.asList(s -> s.toArray(), s -> s.forEach(e -> {
    }), s -> s.reduce(Long::sum));
    List<UnaryOperator<LongStream>> intermediateOps = Arrays.asList(s -> s.parallel(), // The following ensures the wrapping spliterator is tested
    s -> s.map(i -> i).parallel());
    for (int i = 0; i < terminalOps.size(); i++) {
        Consumer<LongStream> terminalOp = terminalOps.get(i);
        setContext("termOpIndex", i);
        for (int j = 0; j < intermediateOps.size(); j++) {
            setContext("intOpIndex", j);
            UnaryOperator<LongStream> intermediateOp = intermediateOps.get(j);
            for (boolean proxyEstimateSize : new boolean[] { false, true }) {
                setContext("proxyEstimateSize", proxyEstimateSize);
                // Size is assumed to be larger than the target size for no splitting
                // @@@ Need way to obtain the target size
                Spliterator.OfLong sp = intermediateOp.apply(LongStream.range(0, 1000)).spliterator();
                ProxyNoExactSizeSpliterator.OfLong psp = new ProxyNoExactSizeSpliterator.OfLong(sp, proxyEstimateSize);
                LongStream s = StreamSupport.longStream(psp, true);
                terminalOp.accept(s);
                Assert.assertTrue(psp.splits > 0, String.format("Number of splits should be greater that zero when proxyEstimateSize is %s", proxyEstimateSize));
                Assert.assertTrue(psp.prefixSplits > 0, String.format("Number of non-null prefix splits should be greater that zero when proxyEstimateSize is %s", proxyEstimateSize));
                Assert.assertTrue(psp.sizeOnTraversal < 1000, String.format("Size on traversal of last split should be less than the size of the list, %d, when proxyEstimateSize is %s", 1000, proxyEstimateSize));
            }
        }
    }
}

Example 7 with Spliterator

use of java.util.Spliterator in project jdk8u_jdk by JetBrains.

the class DoublePipeline method forEachWithCancel.

@Override
final void forEachWithCancel(Spliterator<Double> spliterator, Sink<Double> sink) {
    Spliterator.OfDouble spl = adapt(spliterator);
    DoubleConsumer adaptedSink = adapt(sink);
    do {
    } while (!sink.cancellationRequested() && spl.tryAdvance(adaptedSink));
}

Example 8 with Spliterator

use of java.util.Spliterator in project jdk8u_jdk by JetBrains.

the class LongPipeline method forEachWithCancel.

@Override
final void forEachWithCancel(Spliterator<Long> spliterator, Sink<Long> sink) {
    Spliterator.OfLong spl = adapt(spliterator);
    LongConsumer adaptedSink = adapt(sink);
    do {
    } while (!sink.cancellationRequested() && spl.tryAdvance(adaptedSink));
}

Example 9 with Spliterator

use of java.util.Spliterator in project j2objc by google.

the class LongPipeline method forEachWithCancel.

@Override
public final void forEachWithCancel(Spliterator<Long> spliterator, Sink<Long> sink) {
    Spliterator.OfLong spl = adapt(spliterator);
    LongConsumer adaptedSink = adapt(sink);
    do {
    } while (!sink.cancellationRequested() && spl.tryAdvance(adaptedSink));
}

Example 10 with Spliterator

use of java.util.Spliterator in project jdk8u_jdk by JetBrains.

the class DistinctOps method makeRef.

/**
     * Appends a "distinct" operation to the provided stream, and returns the
     * new stream.
     *
     * @param <T> the type of both input and output elements
     * @param upstream a reference stream with element type T
     * @return the new stream
     */
static <T> ReferencePipeline<T, T> makeRef(AbstractPipeline<?, T, ?> upstream) {
    return new ReferencePipeline.StatefulOp<T, T>(upstream, StreamShape.REFERENCE, StreamOpFlag.IS_DISTINCT | StreamOpFlag.NOT_SIZED) {

        <P_IN> Node<T> reduce(PipelineHelper<T> helper, Spliterator<P_IN> spliterator) {
            // If the stream is SORTED then it should also be ORDERED so the following will also
            // preserve the sort order
            TerminalOp<T, LinkedHashSet<T>> reduceOp = ReduceOps.<T, LinkedHashSet<T>>makeRef(LinkedHashSet::new, LinkedHashSet::add, LinkedHashSet::addAll);
            return Nodes.node(reduceOp.evaluateParallel(helper, spliterator));
        }

        @Override
        <P_IN> Node<T> opEvaluateParallel(PipelineHelper<T> helper, Spliterator<P_IN> spliterator, IntFunction<T[]> generator) {
            if (StreamOpFlag.DISTINCT.isKnown(helper.getStreamAndOpFlags())) {
                // No-op
                return helper.evaluate(spliterator, false, generator);
            } else if (StreamOpFlag.ORDERED.isKnown(helper.getStreamAndOpFlags())) {
                return reduce(helper, spliterator);
            } else {
                // Holder of null state since ConcurrentHashMap does not support null values
                AtomicBoolean seenNull = new AtomicBoolean(false);
                ConcurrentHashMap<T, Boolean> map = new ConcurrentHashMap<>();
                TerminalOp<T, Void> forEachOp = ForEachOps.makeRef(t -> {
                    if (t == null)
                        seenNull.set(true);
                    else
                        map.putIfAbsent(t, Boolean.TRUE);
                }, false);
                forEachOp.evaluateParallel(helper, spliterator);
                // If null has been seen then copy the key set into a HashSet that supports null values
                // and add null
                Set<T> keys = map.keySet();
                if (seenNull.get()) {
                    // TODO Implement a more efficient set-union view, rather than copying
                    keys = new HashSet<>(keys);
                    keys.add(null);
                }
                return Nodes.node(keys);
            }
        }

        @Override
        <P_IN> Spliterator<T> opEvaluateParallelLazy(PipelineHelper<T> helper, Spliterator<P_IN> spliterator) {
            if (StreamOpFlag.DISTINCT.isKnown(helper.getStreamAndOpFlags())) {
                // No-op
                return helper.wrapSpliterator(spliterator);
            } else if (StreamOpFlag.ORDERED.isKnown(helper.getStreamAndOpFlags())) {
                // Not lazy, barrier required to preserve order
                return reduce(helper, spliterator).spliterator();
            } else {
                // Lazy
                return new StreamSpliterators.DistinctSpliterator<>(helper.wrapSpliterator(spliterator));
            }
        }

        @Override
        Sink<T> opWrapSink(int flags, Sink<T> sink) {
            Objects.requireNonNull(sink);
            if (StreamOpFlag.DISTINCT.isKnown(flags)) {
                return sink;
            } else if (StreamOpFlag.SORTED.isKnown(flags)) {
                return new Sink.ChainedReference<T, T>(sink) {

                    boolean seenNull;

                    T lastSeen;

                    @Override
                    public void begin(long size) {
                        seenNull = false;
                        lastSeen = null;
                        downstream.begin(-1);
                    }

                    @Override
                    public void end() {
                        seenNull = false;
                        lastSeen = null;
                        downstream.end();
                    }

                    @Override
                    public void accept(T t) {
                        if (t == null) {
                            if (!seenNull) {
                                seenNull = true;
                                downstream.accept(lastSeen = null);
                            }
                        } else if (lastSeen == null || !t.equals(lastSeen)) {
                            downstream.accept(lastSeen = t);
                        }
                    }
                };
            } else {
                return new Sink.ChainedReference<T, T>(sink) {

                    Set<T> seen;

                    @Override
                    public void begin(long size) {
                        seen = new HashSet<>();
                        downstream.begin(-1);
                    }

                    @Override
                    public void end() {
                        seen = null;
                        downstream.end();
                    }

                    @Override
                    public void accept(T t) {
                        if (!seen.contains(t)) {
                            seen.add(t);
                            downstream.accept(t);
                        }
                    }
                };
            }
        }
    };
}