Java IndexHelper.deserializeIndex方法代码示例

import org.apache.cassandra.io.sstable.IndexHelper; //导入方法依赖的package包/类
public IndexedSliceReader(SSTableReader sstable, FileDataInput input, ByteBuffer startColumn, ByteBuffer finishColumn, boolean reversed)
{
    this.file = input;
    this.startColumn = startColumn;
    this.finishColumn = finishColumn;
    this.reversed = reversed;
    comparator = sstable.metadata.comparator;
    try
    {
        IndexHelper.skipBloomFilter(file);
        indexes = IndexHelper.deserializeIndex(file);

        emptyColumnFamily = ColumnFamily.serializer().deserializeFromSSTableNoColumns(ColumnFamily.create(sstable.metadata), file);
        fetcher = indexes == null ? new SimpleBlockFetcher() : new IndexedBlockFetcher();
    }
    catch (IOException e)
    {
        throw new IOError(e);
    }
}
 

import org.apache.cassandra.io.sstable.IndexHelper; //导入方法依赖的package包/类
private void read(SSTableReader sstable, FileDataInput file)
throws IOException
{
    Filter bf = IndexHelper.defreezeBloomFilter(file, sstable.descriptor.usesOldBloomFilter);
    List<IndexHelper.IndexInfo> indexList = IndexHelper.deserializeIndex(file);

    // we can stop early if bloom filter says none of the columns actually exist -- but,
    // we can't stop before initializing the cf above, in case there's a relevant tombstone
    ColumnFamilySerializer serializer = ColumnFamily.serializer();
    try {
        cf = serializer.deserializeFromSSTableNoColumns(ColumnFamily.create(sstable.metadata), file);
    } catch (Exception e) {
        throw new IOException
            (serializer + " failed to deserialize " + sstable.getColumnFamilyName() + " with " + sstable.metadata + " from " + file, e);
    }

    List<ByteBuffer> filteredColumnNames = new ArrayList<ByteBuffer>(columns.size());
    for (ByteBuffer name : columns)
    {
        if (bf.isPresent(name))
        {
            filteredColumnNames.add(name);
        }
    }
    if (filteredColumnNames.isEmpty())
        return;

    if (indexList == null)
        readSimpleColumns(file, columns, filteredColumnNames);
    else
        readIndexedColumns(sstable.metadata, file, columns, filteredColumnNames, indexList);

    // create an iterator view of the columns we read
    iter = cf.getSortedColumns().iterator();
}
 

import org.apache.cassandra.io.sstable.IndexHelper; //导入方法依赖的package包/类
/**
 * This slice reader assumes that slices are sorted correctly, e.g. that for forward lookup slices are in
 * lexicographic order of start elements and that for reverse lookup they are in reverse lexicographic order of
 * finish (reverse start) elements. i.e. forward: [a,b],[d,e],[g,h] reverse: [h,g],[e,d],[b,a]. This reader also
 * assumes that validation has been performed in terms of intervals (no overlapping intervals).
 */
public IndexedSliceReader(SSTableReader sstable, RowIndexEntry indexEntry, FileDataInput input, ColumnSlice[] slices, boolean reversed)
{
    Tracing.trace("Seeking to partition indexed section in data file");
    this.sstable = sstable;
    this.originalInput = input;
    this.reversed = reversed;
    this.slices = slices;
    this.comparator = sstable.metadata.comparator;
    this.rangeTombstonesReversed = reversed ? new ArrayDeque<OnDiskAtom>() : null;

    try
    {
        Descriptor.Version version = sstable.descriptor.version;
        if (version.hasPromotedIndexes)
        {
            this.indexes = indexEntry.columnsIndex();
            if (indexes.isEmpty())
            {
                setToRowStart(sstable, indexEntry, input);
                this.emptyColumnFamily = ColumnFamily.create(sstable.metadata);
                emptyColumnFamily.delete(DeletionTime.serializer.deserialize(file));
                fetcher = new SimpleBlockFetcher();
            }
            else
            {
                this.emptyColumnFamily = ColumnFamily.create(sstable.metadata);
                emptyColumnFamily.delete(indexEntry.deletionTime());
                fetcher = new IndexedBlockFetcher(indexEntry.position);
            }
        }
        else
        {
            setToRowStart(sstable, indexEntry, input);
            IndexHelper.skipBloomFilter(file);
            this.indexes = IndexHelper.deserializeIndex(file);
            this.emptyColumnFamily = ColumnFamily.create(sstable.metadata);
            emptyColumnFamily.delete(DeletionTime.serializer.deserialize(file));
            fetcher = indexes.isEmpty()
                    ? new SimpleBlockFetcher()
                    : new IndexedBlockFetcher(file.getFilePointer() + 4); // We still have the column count to
                                                                          // skip to get the basePosition
        }
    }
    catch (IOException e)
    {
        sstable.markSuspect();
        throw new CorruptSSTableException(e, file.getPath());
    }
}