Signed-off-by: Caleb Hulbert <cmhulbert@gmail.com>

…nnel when an exception is thrown during `close()`

* getBlockSize should correspond to readBlock / writeBlock
* useful to have an analogue for readChunk / writeChunk

* that deletes blocks or chunks

* add clarifying javadoc
* test blockSize == chunkSize when not sharded
* fix block / chunk equivalence test and comments

* improve testReadChunkVsBlock

createDatasetAccess() can be private because we don't override it
anywhere. (Maybe we did previously in n5-zarr?)

getDatasetAccess() has to be protected for tests only.
It is better for tests to use the canonical DatasetAccess instead of
creating a separate one, as they did before using createDatasetAccess()

…g via FileChannel.

fix: ensure parent directories exist before writing file for Unsafe
Signed-off-by: Caleb Hulbert <cmhulbert@gmail.com>

…ust specify the TRUNCATE_EXISTING OpenOption. It is much faster

Signed-off-by: Caleb Hulbert <cmhulbert@gmail.com>

…ry (isFile -> throws, null -> creates)

Signed-off-by: Caleb Hulbert <cmhulbert@gmail.com>

Signed-off-by: Caleb Hulbert <cmhulbert@gmail.com>

…writes that also fail on closing the file. It's a bit more involved, since we need to flush the write operation, but the logic is the same as for read

Signed-off-by: Caleb Hulbert <cmhulbert@gmail.com>

* and a test

* Default- and Aggregating-
* add tests

…ment

feat: use the aggregate/prefetch logic with VolatileReadData.

By default, `VolatileReadData.from` now uses AggregatingSliceTrackingLazyRead. This is useful to ensure the default VolatileReadData behaves reasonably even for reading many chunks from the same shard.

The wrapped volatileReadData is closed via the wrapper chain
LazyReadData -> AggregatingSliceTrackingLazyRead -> TrackingLazyRead ->
volatileReadData

No need for DelegatingVolatileReadData.

It doesn't do any prefetching, just keeps track of what has been
materialized (and uses that to avoid materializing slices that are
already fully covered).

instead of "...SliceTracking..." which is not their main feature

* add a test