append(
abortedTxn: AbortedTxn): UnitTransactionIndex
TransactionIndex is a transaction index of a LogSegment.
TransactionIndex is created when:
-
LogSegmentutility is used to open a log segment -
DumpLogSegments tool is used (to dump a transaction index (of a log segment))
Creating TransactionIndex Instance
TransactionIndex takes the following to be created:
-
Underlying file (Java’s File)
TransactionIndex initializes the internal properties.
While being created, TransactionIndex opens a channel to the file if exists already.
append Method
append…FIXME
|
Note
|
|
truncateTo Method
truncateTo(
offset: Long): UnittruncateTo…FIXME
|
Note
|
truncateTo is used when LogSegment is requested to truncate (to a given offset).
|
deleteIfExists Method
deleteIfExists(): BooleandeleteIfExists…FIXME
|
Note
|
deleteIfExists is used when LogSegment is requested to deleteIfExists.
|
collectAbortedTxns Method
collectAbortedTxns(
fetchOffset: Long,
upperBoundOffset: Long): TxnIndexSearchResultcollectAbortedTxns…FIXME
|
Note
|
collectAbortedTxns is used when LogSegment is requested to collectAbortedTxns.
|
Opening FileChannel — openChannel Internal Method
openChannel(): FileChannelopenChannel uses Java’s FileChannel utility to open a file channel to the underlying file for read and write access (and creating a new file unless it exists already).
openChannel registers the FileChannel with the maybeChannel internal registry.
openChannel sets the file position of the FileChannel to be the very end of the file.
|
Note
|
openChannel is used when TransactionIndex is created (and the underlying file is available) and requested for the FileChannel.
|
channel Internal Method
channel(): FileChannelchannel takes the FileChannel out from the maybeChannel internal registry (if available) or opens a new FileChannel.
|
Note
|
channel is used when TransactionIndex is requested to append and truncateTo.
|