private void setToRowStart(SSTableReader reader, RowIndexEntry indexEntry, FileDataInput input)
throws IOException {
if (input == null) {
this.file = sstable.getFileDataInput(indexEntry.position);
} else {
this.file = input;
input.seek(indexEntry.position);
}
sstable.decodeKey(ByteBufferUtil.readWithShortLength(file));
SSTableReader.readRowSize(file, sstable.descriptor);
}
/**
* Retrieves a local subBlock
*
* @param blockId row key
* @param sblockId SubBlock column name
* @param offset inside the sblock
* @return a local sublock
* @throws TException
*/
private LocalBlock getLocalSubBlock(
String subBlockCFName, ByteBuffer blockId, ByteBuffer sblockId, int offset)
throws TException {
DecoratedKey<Token<?>> decoratedKey =
new DecoratedKey<Token<?>>(StorageService.getPartitioner().getToken(blockId), blockId);
Table table = Table.open(cfsKeyspace);
ColumnFamilyStore sblockStore = table.getColumnFamilyStore(subBlockCFName);
Collection<SSTableReader> sstables = sblockStore.getSSTables();
for (SSTableReader sstable : sstables) {
long position = sstable.getPosition(decoratedKey, Operator.EQ);
if (position == -1) continue;
String filename = sstable.descriptor.filenameFor(Component.DATA);
RandomAccessFile raf = null;
int mappedLength = -1;
MappedByteBuffer mappedData = null;
MappedFileDataInput file = null;
try {
raf = new RandomAccessFile(filename, "r");
assert position < raf.length();
mappedLength =
(raf.length() - position) < Integer.MAX_VALUE
? (int) (raf.length() - position)
: Integer.MAX_VALUE;
mappedData = raf.getChannel().map(FileChannel.MapMode.READ_ONLY, position, mappedLength);
file = new MappedFileDataInput(mappedData, filename, 0);
if (file == null) continue;
// Verify key was found in data file
DecoratedKey keyInDisk =
SSTableReader.decodeKey(
sstable.partitioner, sstable.descriptor, ByteBufferUtil.readWithShortLength(file));
assert keyInDisk.equals(decoratedKey)
: String.format("%s != %s in %s", keyInDisk, decoratedKey, file.getPath());
long rowSize = SSTableReader.readRowSize(file, sstable.descriptor);
assert rowSize > 0;
assert rowSize < mappedLength;
Filter bf = IndexHelper.defreezeBloomFilter(file, sstable.descriptor.usesOldBloomFilter);
// verify this column in in this version of the row.
if (!bf.isPresent(sblockId)) continue;
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 {
ColumnFamily cf =
serializer.deserializeFromSSTableNoColumns(
ColumnFamily.create(sstable.metadata), file);
if (cf.isMarkedForDelete()) continue;
} catch (Exception e) {
e.printStackTrace();
throw new IOException(
serializer
+ " failed to deserialize "
+ sstable.getColumnFamilyName()
+ " with "
+ sstable.metadata
+ " from "
+ file,
e);
}
Integer sblockLength = null;
if (indexList == null) sblockLength = seekToSubColumn(sstable.metadata, file, sblockId);
else sblockLength = seekToSubColumn(sstable.metadata, file, sblockId, indexList);
if (sblockLength == null || sblockLength < 0) continue;
int bytesReadFromStart = mappedLength - (int) file.bytesRemaining();
if (logger.isDebugEnabled())
logger.debug("BlockLength = " + sblockLength + " Availible " + file.bytesRemaining());
assert offset <= sblockLength : String.format("%d > %d", offset, sblockLength);
long dataOffset = position + bytesReadFromStart;
if (file.bytesRemaining() == 0 || sblockLength == 0) continue;
return new LocalBlock(file.getPath(), dataOffset + offset, sblockLength - offset);
} catch (IOException e) {
throw new TException(e);
} finally {
FileUtils.closeQuietly(raf);
}
}
return null;
}