com.sleepycat.persist

Interface KeySelector<K>

interface KeySelector<K>

This is package-private to hide it until we implemented unsorted access. Implemented to select keys to be returned by an unsorted ForwardCursor.

The reason for implementing a selector, rather than filtering the objects returned by the ForwardCursor, is to improve performance when not all keys are to be processed. Keys are passed to this interface without retrieving record data or locking, so it is less expensive to return false from this method than to retrieve the object from the cursor.

see EntityIndex#unsortedKeys see EntityIndex#unsortedEntities

Author:

Mark Hayes

Method Summary

Methods

Modifier and Type	Method and Description
boolean	selectKey(K key) Returns whether a given key should be returned via the cursor.

Method Detail

selectKey

boolean selectKey(K key)

Returns whether a given key should be returned via the cursor.

This method should not assume that the given key is for a committed record or not, nor should it assume that the key will be returned via the cursor if this method returns true. The record for this key will not be locked until this method returns. If, when the record is locked, the record is found to be uncommitted or deleted, the key will not be returned via the cursor.