io.deephaven.engine.table.impl.sources.chunkcolumnsource.CharChunkColumnSource Maven / Gradle / Ivy
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/**
* Copyright (c) 2016-2022 Deephaven Data Labs and Patent Pending
*/
package io.deephaven.engine.table.impl.sources.chunkcolumnsource;
import gnu.trove.list.array.TLongArrayList;
import io.deephaven.base.verify.Assert;
import io.deephaven.chunk.attributes.Any;
import io.deephaven.chunk.attributes.Values;
import io.deephaven.engine.table.ChunkSource;
import io.deephaven.engine.table.impl.DefaultGetContext;
import io.deephaven.engine.table.SharedContext;
import io.deephaven.engine.table.impl.AbstractColumnSource;
import io.deephaven.engine.table.impl.ImmutableColumnSourceGetDefaults;
import io.deephaven.chunk.*;
import io.deephaven.engine.rowset.RowSequence;
import io.deephaven.util.QueryConstants;
import io.deephaven.util.SafeCloseable;
import org.apache.commons.lang3.mutable.MutableInt;
import org.jetbrains.annotations.NotNull;
import java.util.ArrayList;
/**
* A column source backed by {@link CharChunk CharChunks}.
*
* The address space of the column source is dense, with each chunk backing a contiguous set of indices. The
* {@link #getChunk(GetContext, RowSequence)}
* call will return the backing chunk or a slice of the backing chunk if possible.
*/
public class CharChunkColumnSource extends AbstractColumnSource implements ImmutableColumnSourceGetDefaults.ForChar, ChunkColumnSource {
private final ArrayList> data = new ArrayList<>();
private final TLongArrayList firstOffsetForData;
private long totalSize = 0;
// region constructor
public CharChunkColumnSource() {
this(new TLongArrayList());
}
protected CharChunkColumnSource(final TLongArrayList firstOffsetForData) {
super(Character.class);
this.firstOffsetForData = firstOffsetForData;
}
// endregion constructor
@Override
public char getChar(final long rowKey) {
if (rowKey < 0 || rowKey >= totalSize) {
return QueryConstants.NULL_CHAR;
}
final int chunkIndex = getChunkIndex(rowKey);
final long offset = firstOffsetForData.getQuick(chunkIndex);
return data.get(chunkIndex).get((int) (rowKey - offset));
}
private final static class ChunkGetContext extends DefaultGetContext {
private final ResettableCharChunk resettableCharChunk = ResettableCharChunk.makeResettableChunk();
public ChunkGetContext(final ChunkSource chunkSource, final int chunkCapacity, final SharedContext sharedContext) {
super(chunkSource, chunkCapacity, sharedContext);
}
@Override
public void close() {
resettableCharChunk.close();
super.close();
}
}
@Override
public GetContext makeGetContext(final int chunkCapacity, final SharedContext sharedContext) {
return new ChunkGetContext(this, chunkCapacity, sharedContext);
}
@Override
public Chunk getChunk(@NotNull final GetContext context, @NotNull final RowSequence rowSequence) {
if (rowSequence.isEmpty()) {
return CharChunk.getEmptyChunk();
}
// if we can slice part of one of our backing chunks, then we will return that instead
if (rowSequence.isContiguous()) {
final long firstKey = rowSequence.firstRowKey();
final int firstChunk = getChunkIndex(firstKey);
final int lastChunk = getChunkIndex(rowSequence.lastRowKey(), firstChunk);
if (firstChunk == lastChunk) {
final int offset = (int) (firstKey - firstOffsetForData.get(firstChunk));
final int length = rowSequence.intSize();
final CharChunk charChunk = data.get(firstChunk);
if (offset == 0 && length == charChunk.size()) {
return charChunk;
}
return ((ChunkGetContext) context).resettableCharChunk.resetFromChunk(charChunk, offset, length);
}
}
return getChunkByFilling(context, rowSequence);
}
@Override
public void fillChunk(@NotNull final FillContext context, @NotNull final WritableChunk destination, @NotNull final RowSequence rowSequence) {
final MutableInt searchStartChunkIndex = new MutableInt(0);
destination.setSize(0);
rowSequence.forAllRowKeyRanges((s, e) -> {
while (s <= e) {
final int chunkIndex = getChunkIndex(s, searchStartChunkIndex.intValue());
final int offsetWithinChunk = (int) (s - firstOffsetForData.get(chunkIndex));
Assert.geqZero(offsetWithinChunk, "offsetWithinChunk");
final CharChunk charChunk = data.get(chunkIndex);
final int chunkSize = charChunk.size();
final long rangeLength = e - s + 1;
final int chunkRemaining = chunkSize - offsetWithinChunk;
final int length = rangeLength > chunkRemaining ? chunkRemaining : (int) rangeLength;
Assert.gtZero(length, "length");
final int currentDestinationSize = destination.size();
destination.copyFromChunk(charChunk, offsetWithinChunk, currentDestinationSize, length);
destination.setSize(currentDestinationSize + length);
s += length;
if (s <= e) {
// We have more of this range to gather from a subsequent chunk.
searchStartChunkIndex.setValue(chunkIndex + 1);
}
}
});
}
@Override
public void fillPrevChunk(@NotNull final FillContext context, @NotNull final WritableChunk destination, @NotNull final RowSequence rowSequence) {
// immutable, so we can delegate to fill
fillChunk(context, destination, rowSequence);
}
/**
* Given a row key within this column's address space; return the chunk index that contains the row key.
*
* @param start the data row key to find the corresponding chunk for
* @return the chunk index within data and offsets
*/
private int getChunkIndex(final long start) {
return getChunkIndex(start, 0);
}
/**
* Given a row key within this column's address space; return the chunk index that contains the row key.
*
* @param start the data row key to find the corresponding chunk for
* @param startChunk the first chunk that may possibly contain start
* @return the chunk index within data and offsets
*/
private int getChunkIndex(final long start, final int startChunk) {
if (start == firstOffsetForData.get(startChunk)) {
return startChunk;
}
int index = firstOffsetForData.binarySearch(start, startChunk, firstOffsetForData.size());
if (index < 0) {
index = -index - 2;
}
return index;
}
/**
* Append a chunk of data to this column source.
*
* The chunk must not be empty (i.e., the size must be greater than zero).
*
* @param chunk the chunk of data to add
*/
public void addChunk(@NotNull final WritableCharChunk chunk) {
Assert.gtZero(chunk.size(), "chunk.size()");
data.add(chunk);
if (data.size() > firstOffsetForData.size()) {
firstOffsetForData.add(totalSize);
}
totalSize += chunk.size();
}
@Override
public void addChunk(@NotNull final WritableChunk chunk) {
addChunk(chunk.asWritableCharChunk());
}
@Override
public void clear() {
totalSize = 0;
data.forEach(SafeCloseable::close);
data.clear();
firstOffsetForData.resetQuick();
}
@Override
public long getSize() {
return totalSize;
}
}