aliehsaeedii commented on code in PR #14957: URL: https://github.com/apache/kafka/pull/14957#discussion_r1422488101
########## streams/src/main/java/org/apache/kafka/streams/state/internals/ReadonlyPartiallyDeserializedSegmentValue.java: ########## @@ -0,0 +1,206 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.kafka.streams.state.internals; + +import org.apache.kafka.streams.query.ResultOrder; + +import java.nio.ByteBuffer; +import java.util.HashMap; +import java.util.Map; + + +final class ReadonlyPartiallyDeserializedSegmentValue { + + private static final int TIMESTAMP_SIZE = 8; + private static final int VALUE_SIZE = 4; + private byte[] segmentValue; + private long nextTimestamp; + private long minTimestamp; + + private int deserIndex = -1; // index up through which this segment has been deserialized (inclusive) + + private Map<Integer, Integer> cumulativeValueSizes; + + private int valuesStartingIndex = -1; // the index of the first value in the segment (but the last one in the list) + private Map<Integer, TimestampAndValueSize> unpackedTimestampAndValueSizes = new HashMap<>(); + private int recordNumber = -1; // number of segment records + + + ReadonlyPartiallyDeserializedSegmentValue(final byte[] segmentValue) { + this.segmentValue = segmentValue; + this.nextTimestamp = + RocksDBVersionedStoreSegmentValueFormatter.getNextTimestamp(segmentValue); + this.minTimestamp = + RocksDBVersionedStoreSegmentValueFormatter.getMinTimestamp(segmentValue); + resetDeserHelpers(); + } + + + public long getMinTimestamp() { + return minTimestamp; + } + + public long getNextTimestamp() { + return nextTimestamp; + } + + public byte[] serialize() { + return segmentValue; + } + + + public RocksDBVersionedStoreSegmentValueFormatter.SegmentValue.SegmentSearchResult find( + final long fromTime, final long toTime, final ResultOrder order, final int index) { + + // this segment does not have any record in query specified time range + if (toTime < minTimestamp || fromTime > nextTimestamp) { + return null; + } + + final boolean isAscending = order.equals(ResultOrder.ASCENDING); + + if (isAscending && valuesStartingIndex == -1) { + findValuesStartingIndex(); + deserIndex = recordNumber; + } + + long currTimestamp = -1; + long currNextTimestamp = -1; + int currIndex = initializeCurrentIndex(index, isAscending); + int cumValueSize = initializeCumvalueSize(index, currIndex, isAscending); + int currValueSize; + + + while (hasStillRecord(currTimestamp, currNextTimestamp, order)) { + if (hasBeenDeserialized(isAscending, currIndex)) { + final TimestampAndValueSize curr; + curr = unpackedTimestampAndValueSizes.get(currIndex); + currTimestamp = curr.timestamp; + cumValueSize = cumulativeValueSizes.get(currIndex); + currValueSize = curr.valueSize; + + // update currValueSize + if (currValueSize == Integer.MIN_VALUE) { + final int timestampSegmentIndex = getTimestampIndex(order, currIndex); + currValueSize = ByteBuffer.wrap(segmentValue).getInt(timestampSegmentIndex + TIMESTAMP_SIZE); + unpackedTimestampAndValueSizes.put(currIndex, new TimestampAndValueSize(currTimestamp, cumValueSize)); + } + + currNextTimestamp = updateCurrNextTimestamp(currIndex, isAscending); + + } else { + final int timestampSegmentIndex = getTimestampIndex(order, currIndex); + currTimestamp = ByteBuffer.wrap(segmentValue).getLong(timestampSegmentIndex); + currValueSize = ByteBuffer.wrap(segmentValue).getInt(timestampSegmentIndex + TIMESTAMP_SIZE); + currNextTimestamp = timestampSegmentIndex == 2 * TIMESTAMP_SIZE + ? nextTimestamp // if this is the first record metadata (timestamp + value size) + : ByteBuffer.wrap(segmentValue).getLong(timestampSegmentIndex - (TIMESTAMP_SIZE + VALUE_SIZE)); + cumValueSize += Math.max(currValueSize, 0); + + // update deserHelpers + deserIndex = currIndex; + unpackedTimestampAndValueSizes.put(currIndex, new TimestampAndValueSize(currTimestamp, currValueSize)); + cumulativeValueSizes.put(currIndex, cumValueSize); + } + + if (currValueSize >= 0) { + final byte[] value = new byte[currValueSize]; + final int valueSegmentIndex = getValueSegmentIndex(order, cumValueSize, currValueSize); + System.arraycopy(segmentValue, valueSegmentIndex, value, 0, currValueSize); + if (currTimestamp <= toTime && currNextTimestamp > fromTime) { + return new RocksDBVersionedStoreSegmentValueFormatter.SegmentValue.SegmentSearchResult(currIndex, currTimestamp, currNextTimestamp, value); + } + } + // prep for next iteration + currIndex = isAscending ? currIndex - 1 : currIndex + 1; + } + // search in segment expected to find result but did not + return null; + } + + private long updateCurrNextTimestamp(final int currIndex, final boolean isAscending) { + if (isAscending) { + return currIndex == recordNumber - 1 ? nextTimestamp : unpackedTimestampAndValueSizes.get(currIndex + 1).timestamp; + } else { + return currIndex == 0 ? nextTimestamp : unpackedTimestampAndValueSizes.get(currIndex - 1).timestamp; + } + } + + private int initializeCumvalueSize(final int index, final int currIndex, final boolean isAscending) { + return (index == Integer.MAX_VALUE || (!isAscending && index == 0)) ? 0 + : isAscending ? cumulativeValueSizes.get(currIndex + 1) + : cumulativeValueSizes.get(currIndex - 1); + } + + private int initializeCurrentIndex(final int index, final boolean isAscending) { + return isAscending && index == Integer.MAX_VALUE ? recordNumber - 1 : index; + } + + + private boolean hasStillRecord(final long currTimestamp, final long currNextTimestamp, final ResultOrder order) { + return order.equals(ResultOrder.ASCENDING) ? currNextTimestamp != nextTimestamp : currTimestamp != minTimestamp; + } + + private boolean hasBeenDeserialized(final boolean isAscending, final int currIndex) { + if (!isAscending) { + return currIndex <= deserIndex; + } + return currIndex >= deserIndex; + } + + private int getValueSegmentIndex(final ResultOrder order, final int currentCumValueSize, final int currValueSize) { + return order.equals(ResultOrder.ASCENDING) ? valuesStartingIndex + (currentCumValueSize - currValueSize) + : segmentValue.length - currentCumValueSize; + } + + private int getTimestampIndex(final ResultOrder order, final int currIndex) { + return order.equals(ResultOrder.ASCENDING) ? valuesStartingIndex - ((recordNumber - currIndex) * (TIMESTAMP_SIZE + VALUE_SIZE)) + : 2 * TIMESTAMP_SIZE + currIndex * (TIMESTAMP_SIZE + VALUE_SIZE); + } + + private void findValuesStartingIndex() { + long currTimestamp = -1; + int currIndex = 0; + int timestampSegmentIndex = 0; + while (currTimestamp != minTimestamp) { + timestampSegmentIndex = 2 * TIMESTAMP_SIZE + currIndex * (TIMESTAMP_SIZE + VALUE_SIZE); + currTimestamp = ByteBuffer.wrap(segmentValue).getLong(timestampSegmentIndex); + unpackedTimestampAndValueSizes.put(currIndex, new TimestampAndValueSize(currTimestamp, Integer.MIN_VALUE)); Review Comment: > We usually use `-1` to indicate "unknown" (not `MIN_VALUE`) In `RocksDBVersionedStoreSegmentValueFormatter` class, `-1` was used for tombstones. That's why I wanted to have something different. should we use `Optional` instead? -- 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. To unsubscribe, e-mail: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
