com.hazelcast.cache

Interface CacheMergePolicy

All Superinterfaces:

Serializable

All Known Subinterfaces:

StorageTypeAwareCacheMergePolicy

All Known Implementing Classes:

HigherHitsCacheMergePolicy, LatestAccessCacheMergePolicy, PassThroughCacheMergePolicy, PutIfAbsentCacheMergePolicy

public interface CacheMergePolicy
extends Serializable

Policy for merging cache entries.

Passed CacheEntryView instances wraps the key and value as their original types with convertion to object from their storage types. If user doesn't need to original types of key and value, (s)he should use StorageTypeAwareCacheMergePolicy which is sub-type of this interface.

Method Summary

Methods

Modifier and Type	Method and Description
Object	merge(String cacheName, CacheEntryView mergingEntry, CacheEntryView existingEntry) Selects one of the merging and existing cache entries to be merged.

Method Detail

merge

Object merge(String cacheName,
           CacheEntryView mergingEntry,
           CacheEntryView existingEntry)

Selects one of the merging and existing cache entries to be merged.

Note that as mentioned also in arguments, the CacheEntryView instance that represents existing cache entry may be null if there is no existing entry for the specified key in the the CacheEntryView instance that represents merging cache entry.

Parameters:

cacheName - name of the cache

mergingEntry - CacheEntryView instance that has cache entry to be merged

existingEntry - CacheEntryView instance that has existing cache entry. This entry may be null if there is no existing cache entry.

Returns:

the selected value for merging