Java tutorial
/* * Licensed 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 io.prestosql.orc.writer; import com.google.common.collect.ImmutableList; import com.google.common.collect.ImmutableMap; import io.airlift.slice.Slice; import io.prestosql.orc.OrcEncoding; import io.prestosql.orc.checkpoint.BooleanStreamCheckpoint; import io.prestosql.orc.checkpoint.LongStreamCheckpoint; import io.prestosql.orc.metadata.ColumnEncoding; import io.prestosql.orc.metadata.CompressedMetadataWriter; import io.prestosql.orc.metadata.CompressionKind; import io.prestosql.orc.metadata.RowGroupIndex; import io.prestosql.orc.metadata.Stream; import io.prestosql.orc.metadata.Stream.StreamKind; import io.prestosql.orc.metadata.statistics.ColumnStatistics; import io.prestosql.orc.metadata.statistics.LongValueStatisticsBuilder; import io.prestosql.orc.stream.LongOutputStream; import io.prestosql.orc.stream.LongOutputStreamDwrf; import io.prestosql.orc.stream.LongOutputStreamV2; import io.prestosql.orc.stream.PresentOutputStream; import io.prestosql.orc.stream.StreamDataOutput; import io.prestosql.spi.block.Block; import io.prestosql.spi.type.Type; import org.openjdk.jol.info.ClassLayout; import java.io.IOException; import java.util.ArrayList; import java.util.List; import java.util.Map; import java.util.Optional; import java.util.function.Supplier; import static com.google.common.base.Preconditions.checkArgument; import static com.google.common.base.Preconditions.checkState; import static io.prestosql.orc.OrcEncoding.DWRF; import static io.prestosql.orc.metadata.ColumnEncoding.ColumnEncodingKind.DIRECT; import static io.prestosql.orc.metadata.ColumnEncoding.ColumnEncodingKind.DIRECT_V2; import static io.prestosql.orc.metadata.CompressionKind.NONE; import static io.prestosql.orc.metadata.Stream.StreamKind.DATA; import static java.util.Objects.requireNonNull; public class LongColumnWriter implements ColumnWriter { private static final int INSTANCE_SIZE = ClassLayout.parseClass(LongColumnWriter.class).instanceSize(); private final int column; private final Type type; private final boolean compressed; private final ColumnEncoding columnEncoding; private final LongOutputStream dataStream; private final PresentOutputStream presentStream; private final List<ColumnStatistics> rowGroupColumnStatistics = new ArrayList<>(); private final Supplier<LongValueStatisticsBuilder> statisticsBuilderSupplier; private LongValueStatisticsBuilder statisticsBuilder; private boolean closed; public LongColumnWriter(int column, Type type, CompressionKind compression, int bufferSize, OrcEncoding orcEncoding, Supplier<LongValueStatisticsBuilder> statisticsBuilderSupplier) { checkArgument(column >= 0, "column is negative"); this.column = column; this.type = requireNonNull(type, "type is null"); this.compressed = requireNonNull(compression, "compression is null") != NONE; if (orcEncoding == DWRF) { this.columnEncoding = new ColumnEncoding(DIRECT, 0); this.dataStream = new LongOutputStreamDwrf(compression, bufferSize, true, DATA); } else { this.columnEncoding = new ColumnEncoding(DIRECT_V2, 0); this.dataStream = new LongOutputStreamV2(compression, bufferSize, true, DATA); } this.presentStream = new PresentOutputStream(compression, bufferSize); this.statisticsBuilderSupplier = requireNonNull(statisticsBuilderSupplier, "statisticsBuilderSupplier is null"); this.statisticsBuilder = statisticsBuilderSupplier.get(); } @Override public Map<Integer, ColumnEncoding> getColumnEncodings() { return ImmutableMap.of(column, columnEncoding); } @Override public void beginRowGroup() { presentStream.recordCheckpoint(); dataStream.recordCheckpoint(); } @Override public void writeBlock(Block block) { checkState(!closed); checkArgument(block.getPositionCount() > 0, "Block is empty"); // record nulls for (int position = 0; position < block.getPositionCount(); position++) { presentStream.writeBoolean(!block.isNull(position)); } // record values for (int position = 0; position < block.getPositionCount(); position++) { if (!block.isNull(position)) { long value = type.getLong(block, position); dataStream.writeLong(value); statisticsBuilder.addValue(value); } } } @Override public Map<Integer, ColumnStatistics> finishRowGroup() { checkState(!closed); ColumnStatistics statistics = statisticsBuilder.buildColumnStatistics(); rowGroupColumnStatistics.add(statistics); statisticsBuilder = statisticsBuilderSupplier.get(); return ImmutableMap.of(column, statistics); } @Override public void close() { closed = true; dataStream.close(); presentStream.close(); } @Override public Map<Integer, ColumnStatistics> getColumnStripeStatistics() { checkState(closed); return ImmutableMap.of(column, ColumnStatistics.mergeColumnStatistics(rowGroupColumnStatistics)); } @Override public List<StreamDataOutput> getIndexStreams(CompressedMetadataWriter metadataWriter) throws IOException { checkState(closed); ImmutableList.Builder<RowGroupIndex> rowGroupIndexes = ImmutableList.builder(); List<LongStreamCheckpoint> dataCheckpoints = dataStream.getCheckpoints(); Optional<List<BooleanStreamCheckpoint>> presentCheckpoints = presentStream.getCheckpoints(); for (int i = 0; i < rowGroupColumnStatistics.size(); i++) { int groupId = i; ColumnStatistics columnStatistics = rowGroupColumnStatistics.get(groupId); LongStreamCheckpoint dataCheckpoint = dataCheckpoints.get(groupId); Optional<BooleanStreamCheckpoint> presentCheckpoint = presentCheckpoints .map(checkpoints -> checkpoints.get(groupId)); List<Integer> positions = createLongColumnPositionList(compressed, dataCheckpoint, presentCheckpoint); rowGroupIndexes.add(new RowGroupIndex(positions, columnStatistics)); } Slice slice = metadataWriter.writeRowIndexes(rowGroupIndexes.build()); Stream stream = new Stream(column, StreamKind.ROW_INDEX, slice.length(), false); return ImmutableList.of(new StreamDataOutput(slice, stream)); } private static List<Integer> createLongColumnPositionList(boolean compressed, LongStreamCheckpoint dataCheckpoint, Optional<BooleanStreamCheckpoint> presentCheckpoint) { ImmutableList.Builder<Integer> positionList = ImmutableList.builder(); presentCheckpoint.ifPresent( booleanStreamCheckpoint -> positionList.addAll(booleanStreamCheckpoint.toPositionList(compressed))); positionList.addAll(dataCheckpoint.toPositionList(compressed)); return positionList.build(); } @Override public List<StreamDataOutput> getDataStreams() { checkState(closed); ImmutableList.Builder<StreamDataOutput> outputDataStreams = ImmutableList.builder(); presentStream.getStreamDataOutput(column).ifPresent(outputDataStreams::add); outputDataStreams.add(dataStream.getStreamDataOutput(column)); return outputDataStreams.build(); } @Override public long getBufferedBytes() { return dataStream.getBufferedBytes() + presentStream.getBufferedBytes(); } @Override public long getRetainedBytes() { long retainedBytes = INSTANCE_SIZE + dataStream.getRetainedBytes() + presentStream.getRetainedBytes(); for (ColumnStatistics statistics : rowGroupColumnStatistics) { retainedBytes += statistics.getRetainedSizeInBytes(); } return retainedBytes; } @Override public void reset() { closed = false; dataStream.reset(); presentStream.reset(); rowGroupColumnStatistics.clear(); statisticsBuilder = statisticsBuilderSupplier.get(); } }