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/**
* Copyright (c) 2016-2022 Deephaven Data Labs and Patent Pending
*/
package io.deephaven.engine.page;
import io.deephaven.util.datastructures.LongSizedDataStructure;
import io.deephaven.chunk.attributes.Any;
import io.deephaven.engine.table.ChunkSource;
import io.deephaven.engine.table.impl.DefaultChunkSource;
import io.deephaven.chunk.WritableChunk;
import io.deephaven.engine.rowset.RowSequence;
import io.deephaven.engine.rowset.RowSet;
import io.deephaven.util.annotations.FinalDefault;
import org.jetbrains.annotations.NotNull;
/**
* Pages are {@link PagingChunkSource PagingChunkSources} that can supply values from a subset of a contiguous block of
* row key space beginning at {@link #firstRowOffset()} and continuing to {@link #firstRowOffset()} +
* {@link #maxRow(long)}. Not all row keys within the range may be valid; that is, pages may be sparse.
*
* Pages may be held within one or more {@link PageStore} instances. The PageStore is responsible for determining which
* row keys in absolute space are mapped to a particular Page. Pages need only concern themselves with lower order bits
* of the row keys they are asked for, after applying their {@link #mask()}.
*/
public interface Page extends PagingChunkSource {
/**
* @return the first row of this page, after applying the {@link #mask()}, which refers to the first row of this
* page.
*/
long firstRowOffset();
/**
* @param rowKey Any row key contained on this page
* @return The first row key of this page, located in the same way as {@code rowKey}
*/
@FinalDefault
default long firstRow(final long rowKey) {
return (rowKey & ~mask()) | firstRowOffset();
}
/**
* @return The offset for the given row key in this page, in [0, {@code maxRow(rowKey)}].
*/
@FinalDefault
default long getRowOffset(final long rowKey) {
return (rowKey & mask()) - firstRowOffset();
}
/**
* Helper defaults for general pages.
*/
interface WithDefaults extends Page, DefaultChunkSource {
@Override
@FinalDefault
default void fillChunkAppend(
@NotNull final FillContext context,
@NotNull final WritableChunk destination,
@NotNull final RowSequence.Iterator rowSequenceIterator) {
fillChunkAppend(context, destination,
rowSequenceIterator.getNextRowSequenceThrough(maxRow(rowSequenceIterator.peekNextKey())));
}
@Override
@FinalDefault
default void fillChunk(@NotNull final FillContext context,
@NotNull final WritableChunk destination, @NotNull final RowSequence rowSequence) {
destination.setSize(0);
fillChunkAppend(context, destination, rowSequence);
}
/**
* Appends the values referenced by {@code orderKeys} onto {@code destination}. {@code orderKeys} are assumed to
* be entirely contained on this {@code Page}.
*/
void fillChunkAppend(@NotNull FillContext context, @NotNull WritableChunk destination,
@NotNull RowSequence rowSequence);
}
/**
* Helper defaults for pages that represent a repeating value, e.g. null or partitioning column regions.
*/
interface WithDefaultsForRepeatingValues extends Page, DefaultChunkSource {
@Override
@FinalDefault
default void fillChunkAppend(
@NotNull final FillContext context,
@NotNull final WritableChunk destination,
@NotNull final RowSequence.Iterator rowSequenceIterator) {
fillChunkAppend(context, destination, LongSizedDataStructure.intSize("fillChunkAppend",
rowSequenceIterator.advanceAndGetPositionDistance(maxRow(rowSequenceIterator.peekNextKey()) + 1)));
}
@Override
@FinalDefault
default void fillChunk(@NotNull final FillContext context,
@NotNull final WritableChunk destination, @NotNull final RowSequence rowSequence) {
destination.setSize(0);
fillChunkAppend(context, destination, rowSequence.intSize());
}
/**
* Appends the values repeating value {@code length} times to {@code destination}.
*/
void fillChunkAppend(@NotNull FillContext context, @NotNull WritableChunk destination,
int length);
}
/**
* Assuming {@code rowSequenceIterator} is position at its first row key on this page, consume all keys on this
* page.
*
* @param rowSequenceIterator The iterator to advance
*/
@FinalDefault
default void advanceToNextPage(@NotNull final RowSequence.Iterator rowSequenceIterator) {
rowSequenceIterator.advance(maxRow(rowSequenceIterator.peekNextKey()) + 1);
}
/**
* Assuming {@code rowSequenceIterator} is position at its first row key on this page, consume all keys on this page
* and return the number of keys consumed.
*
* @param rowSequenceIterator The iterator to advance
*/
@FinalDefault
default long advanceToNextPageAndGetPositionDistance(@NotNull final RowSequence.Iterator rowSequenceIterator) {
return rowSequenceIterator.advanceAndGetPositionDistance(maxRow(rowSequenceIterator.peekNextKey()) + 1);
}
/**
* Assuming {@code searchIterator} is position at its first row key on this page, consume all keys on this page.
*
* @param searchIterator The iterator to advance
* @return The result of {@link RowSet.SearchIterator#advance(long)}
*/
@FinalDefault
default boolean advanceToNextPage(@NotNull final RowSet.SearchIterator searchIterator) {
return searchIterator.advance(maxRow(searchIterator.currentValue()) + 1);
}
}