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ASF GitHub Bot logged work on BEAM-7013: ---------------------------------------- Author: ASF GitHub Bot Created on: 15/Aug/19 16:33 Start Date: 15/Aug/19 16:33 Worklog Time Spent: 10m Work Description: zfraa commented on pull request #9144: [BEAM-7013] Integrating ZetaSketch's HLL++ algorithm with Beam URL: https://github.com/apache/beam/pull/9144#discussion_r313891470 ########## File path: sdks/java/extensions/zetasketch/src/main/java/org/apache/beam/sdk/extensions/zetasketch/HllCountMergePartialFn.java ########## @@ -44,109 +37,55 @@ private HllCountMergePartialFn() {} return new HllCountMergePartialFn(); } - /** - * Accumulator for the {@link HllCount.MergePartial} combiner. Cannot use {@link - * HyperLogLogPlusPlus} directly because we need an "identity element" for the {@code merge} - * operation, and we are not able to create such "identity element" of type {@link - * HyperLogLogPlusPlus} without knowing the sketch precision and value type. - */ - static final class HyperLogLogPlusPlusWrapper<T> { - @Nullable private HyperLogLogPlusPlus<T> hll; - - private HyperLogLogPlusPlusWrapper(@Nullable HyperLogLogPlusPlus<T> hll) { - this.hll = hll; - } - } - - /** - * Coder for the {@link HyperLogLogPlusPlusWrapper} class with generic type parameter {@code T}. - */ - private static final class HyperLogLogPlusPlusWrapperCoder<T> - extends AtomicCoder<HyperLogLogPlusPlusWrapper<T>> { - - private static final HyperLogLogPlusPlusWrapperCoder<?> INSTANCE = - new HyperLogLogPlusPlusWrapperCoder<>(); - - private final Coder<HyperLogLogPlusPlus<T>> nullableHllCoder = - NullableCoder.of(HyperLogLogPlusPlusCoder.of()); - - // Generic singleton factory pattern; the coder works for all HyperLogLogPlusPlusWrapper objects - // at runtime regardless of type T - @SuppressWarnings("unchecked") - static <T> HyperLogLogPlusPlusWrapperCoder<T> of() { - return (HyperLogLogPlusPlusWrapperCoder<T>) INSTANCE; - } - - @Override - public void encode(HyperLogLogPlusPlusWrapper<T> value, OutputStream outStream) - throws IOException { - nullableHllCoder.encode(value.hll, outStream); - } - - @Override - public HyperLogLogPlusPlusWrapper<T> decode(InputStream inStream) throws IOException { - return new HyperLogLogPlusPlusWrapper<T>(nullableHllCoder.decode(inStream)); - } - - @Override - public void verifyDeterministic() throws NonDeterministicException { - nullableHllCoder.verifyDeterministic(); - } - } - @Override - public Coder<HyperLogLogPlusPlusWrapper<T>> getAccumulatorCoder( + public Coder<HyperLogLogPlusPlus<T>> getAccumulatorCoder( CoderRegistry registry, Coder<byte[]> inputCoder) { - return HyperLogLogPlusPlusWrapperCoder.of(); + return NullableCoder.of(HyperLogLogPlusPlusCoder.of()); } @Override - public HyperLogLogPlusPlusWrapper<T> createAccumulator() { - return new HyperLogLogPlusPlusWrapper<>(null); + public HyperLogLogPlusPlus<T> createAccumulator() { + return null; } @Override - public HyperLogLogPlusPlusWrapper<T> addInput( - HyperLogLogPlusPlusWrapper<T> accumulator, byte[] input) { - if (accumulator.hll == null) { + public HyperLogLogPlusPlus<T> addInput(HyperLogLogPlusPlus<T> accumulator, byte[] input) { + if (accumulator == null) { @SuppressWarnings("unchecked") - HyperLogLogPlusPlus<T> hll = (HyperLogLogPlusPlus<T>) HyperLogLogPlusPlus.forProto(input); - accumulator.hll = hll; + HyperLogLogPlusPlus<T> result = (HyperLogLogPlusPlus<T>) HyperLogLogPlusPlus.forProto(input); + return result; } else { - accumulator.hll.merge(input); + accumulator.merge(input); + return accumulator; } - return accumulator; } @Override - public HyperLogLogPlusPlusWrapper<T> mergeAccumulators( - Iterable<HyperLogLogPlusPlusWrapper<T>> accumulators) { - HyperLogLogPlusPlusWrapper<T> merged = createAccumulator(); - for (HyperLogLogPlusPlusWrapper<T> accumulator : accumulators) { - if (accumulator.hll == null) { + public HyperLogLogPlusPlus<T> mergeAccumulators(Iterable<HyperLogLogPlusPlus<T>> accumulators) { + HyperLogLogPlusPlus<T> merged = createAccumulator(); Review comment: Why not set this to null directly? (I find that easier to read, but up to your preference!) ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org Issue Time Tracking ------------------- Worklog Id: (was: 295527) Time Spent: 17h 40m (was: 17.5h) > A new count distinct transform based on BigQuery compatible HyperLogLog++ > implementation > ---------------------------------------------------------------------------------------- > > Key: BEAM-7013 > URL: https://issues.apache.org/jira/browse/BEAM-7013 > Project: Beam > Issue Type: New Feature > Components: extensions-java-sketching, sdk-java-core > Reporter: Yueyang Qiu > Assignee: Yueyang Qiu > Priority: Major > Fix For: 2.16.0 > > Time Spent: 17h 40m > Remaining Estimate: 0h > -- This message was sent by Atlassian JIRA (v7.6.14#76016)