public Table(StorageState storageState, FileData fileData) { _storageState = storageState; try { _fileData = fileData; if (_storageState.Options.MaxBlockCacheSizePerTableFile > 0) { _blockCache = new LruCache<BlockHandle, Block>(_storageState.Options.MaxBlockCacheSizePerTableFile); } if (fileData.Size < Footer.EncodedLength) throw new CorruptedDataException("File is too short to be an sstable"); var footer = new Footer(); using (var accessor = fileData.File.CreateAccessor(fileData.Size - Footer.EncodedLength, Footer.EncodedLength)) { footer.DecodeFrom(accessor); } var readOptions = new ReadOptions { VerifyChecksums = _storageState.Options.ParanoidChecks }; _indexBlock = new Block(_storageState.Options, readOptions, footer.IndexHandle, fileData); _indexBlock.IncrementUsage(); if (_storageState.Options.FilterPolicy == null) return; // we don't need any metadata using (var metaBlock = new Block(_storageState.Options, readOptions, footer.MetaIndexHandle, fileData)) using (var iterator = metaBlock.CreateIterator(CaseInsensitiveComparator.Default)) { var filterName = ("filter." + _storageState.Options.FilterPolicy.Name); iterator.Seek(filterName); if (iterator.IsValid && CaseInsensitiveComparator.Default.Compare(filterName, iterator.Key) == 0) { var handle = new BlockHandle(); using (var stream = iterator.CreateValueStream()) { handle.DecodeFrom(stream); } var filterAccessor = _fileData.File.CreateAccessor(handle.Position, handle.Count); try { _filter = _storageState.Options.FilterPolicy.CreateFilter(filterAccessor); } catch (Exception) { if (_filter == null) filterAccessor.Dispose(); else _filter.Dispose(); throw; } } } } catch (Exception) { Dispose(); throw; } }
internal IIterator CreateBlockIterator(ReadOptions readOptions, BlockHandle handle) { if (_blockCache == null) { Block uncachedBlock = null; IIterator blockIterator = null; try { uncachedBlock = new Block(_storageState.Options, readOptions, handle, _fileData); // uncachedBlock.IncrementUsage(); - intentionally not calling this, will be disposed when the iterator is disposed blockIterator = uncachedBlock.CreateIterator(_storageState.InternalKeyComparator); return blockIterator; } catch (Exception) { if (uncachedBlock != null) uncachedBlock.Dispose(); if (blockIterator != null) blockIterator.Dispose(); throw; } } Block value; if (_blockCache.TryGet(handle, out value)) { return value.CreateIterator(_storageState.InternalKeyComparator); } var block = new Block(_storageState.Options, readOptions, handle, _fileData); block.IncrementUsage(); // the cache is using this, so avoid having it disposed by the cache while in use _blockCache.Set(handle, block); return block.CreateIterator(_storageState.InternalKeyComparator); }