io.deephaven.engine.table.impl.sources.ChunkedBackingStoreExposedWritableSource Maven / Gradle / Ivy
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/**
* Copyright (c) 2016-2022 Deephaven Data Labs and Patent Pending
*/
package io.deephaven.engine.table.impl.sources;
import io.deephaven.chunk.ResettableWritableChunk;
import io.deephaven.engine.table.ColumnSource;
import org.jetbrains.annotations.NotNull;
/**
* Writable sources that use simple arrays to back contiguous regions may implement this interface, allowing callers to
* reach directly into their storage in order to fill them without the need for additional array copies.
*/
public interface ChunkedBackingStoreExposedWritableSource {
/**
* Returns true if a given column source exposes a chunked backing store
*
* @param cs the column source to test
* @return true if the column source exposes a chunked backing store
*/
static boolean exposesChunkedBackingStore(ColumnSource cs) {
return cs instanceof ChunkedBackingStoreExposedWritableSource
&& ((ChunkedBackingStoreExposedWritableSource) cs).exposesChunkedBackingStore();
}
/**
* Does this column source provide a chunked exposed backing store?
*
* @return true if this column source provides a chunked backing store, false otherwise
*/
default boolean exposesChunkedBackingStore() {
return true;
}
/**
* Resets the given chunk to provide a write-through reference to our backing array.
*
* Note: This is unsafe to use if previous tracking has been enabled!
*
* @param chunk the writable chunk to reset to our backing array.
* @param position position that we require
* @return the first position addressable by the chunk
*/
long resetWritableChunkToBackingStore(@NotNull ResettableWritableChunk chunk, long position);
/**
* Resets the given chunk to provide a write-through reference to our backing array.
*
* Note: This is unsafe to use if previous tracking has been enabled!
*
* @param chunk the writable chunk to reset to a slice of our backing array.
* @param position position of the first value in the returned chunk
* @return the capacity of the returned chunk
*/
long resetWritableChunkToBackingStoreSlice(@NotNull ResettableWritableChunk chunk, long position);
}