Field Detail

• cellSetNextRow

  private Cell cellSetNextRow

• snapshotNextRow

  private Cell snapshotNextRow

• cellSetItRow

  private Cell cellSetItRow

• snapshotItRow

  private Cell snapshotItRow

• cellSetIt

  private Iterator<Cell> cellSetIt

• snapshotIt

  private Iterator<Cell> snapshotIt

• cellSetAtCreation

  private CellSkipListSet cellSetAtCreation

• snapshotAtCreation

  private CellSkipListSet snapshotAtCreation

• theNext

  private Cell theNext

• allocatorAtCreation

  volatile MemStoreLAB allocatorAtCreation

• snapshotAllocatorAtCreation

  volatile MemStoreLAB snapshotAllocatorAtCreation

• stopSkippingCellsIfNextRow

  private boolean stopSkippingCellsIfNextRow

• stopSkippingKVsRow

  private Cell stopSkippingKVsRow

• readPoint

  private long readPoint

Constructor Detail

• DefaultMemStore.MemStoreScanner

  DefaultMemStore.MemStoreScanner(long readPoint)

Method Detail

• getNext

  private Cell getNext(Iterator<Cell> it)

  Lock on 'this' must be held by caller.

  Parameters:

  it -

  Returns:

  Next Cell

• seek

  public boolean seek(Cell key)

  Set the scanner at the seek key. Must be called only once: there is no thread safety between the scanner and the memStore.

  Parameters:

  key - seek value

  Returns:

  false if the key is null or if there is no data

• seekInSubLists

  private boolean seekInSubLists(Cell key)

  (Re)initialize the iterators after a seek or a reseek.

• reseek

  public boolean reseek(Cell key)

  Move forward on the sub-lists set previously by seek.

  Parameters:

  key - seek value (should be non-null)

  Returns:

  true if there is at least one KV to read, false otherwise

• peek

  public Cell peek()

  Description copied from interface: KeyValueScanner
  Look at the next Cell in this scanner, but do not iterate scanner.

  Returns:

  the next Cell

• next

  public Cell next()

  Description copied from interface: KeyValueScanner
  Return the next Cell in this scanner, iterating the scanner

  Returns:

  the next Cell

• getLowest

  private Cell getLowest(Cell first,
               Cell second)

• getHighest

  private Cell getHighest(Cell first,
                Cell second)

• close

  public void close()

  Description copied from interface: KeyValueScanner
  Close the KeyValue scanner.

• getSequenceID

  public long getSequenceID()

  MemStoreScanner returns max value as sequence id because it will always have the latest data among all files.

• shouldUseScanner

  public boolean shouldUseScanner(Scan scan,
                         Store store,
                         long oldestUnexpiredTS)

  Description copied from interface: KeyValueScanner
  Allows to filter out scanners (both StoreFile and memstore) that we don't want to use based on criteria such as Bloom filters and timestamp ranges.

  Specified by:

  shouldUseScanner in interface KeyValueScanner

  Overrides:

  shouldUseScanner in class NonLazyKeyValueScanner

  Parameters:

  scan - the scan that we are selecting scanners for

  store - the store we are performing the scan on.

  oldestUnexpiredTS - the oldest timestamp we are interested in for this query, based on TTL

  Returns:

  true if the scanner should be included in the query

• backwardSeek

  public boolean backwardSeek(Cell key)

  Seek scanner to the given key first. If it returns false(means peek()==null) or scanner's peek row is bigger than row of given key, seek the scanner to the previous row of given key

  Parameters:

  key - seek KeyValue

  Returns:

  true if the scanner is at the valid KeyValue, false if such KeyValue does not exist

• seekToPreviousRow

  public boolean seekToPreviousRow(Cell originalKey)

  Separately get the KeyValue before the specified key from kvset and snapshotset, and use the row of higher one as the previous row of specified key, then seek to the first KeyValue of previous row

  Parameters:

  originalKey - seek value

  Returns:

  true if the scanner at the first valid Cell of previous row, false if not existing such Cell

• seekToLastRow

  public boolean seekToLastRow()

  Description copied from interface: KeyValueScanner
  Seek the scanner at the first KeyValue of last row

  Returns:

  true if scanner has values left, false if the underlying data is empty