### Question:
MemcachedRegion implements Region { @Override public long nextTimestamp() { long next = hibernateCacheTimestamper.next(); log.debug("region nextTimestamp : {}", next); return next; } MemcachedRegion(CacheNamespace cacheNamespace, OverridableReadOnlyProperties properties, CacheDataDescription metadata, Settings settings,
                           MemcachedAdapter memcachedAdapter, HibernateCacheTimestamper hibernateCacheTimestamper); CacheNamespace getCacheNamespace(); OverridableReadOnlyProperties getProperties(); CacheDataDescription getMetadata(); Settings getSettings(); MemcachedAdapter getMemcachedAdapter(); HibernateCacheTimestamper getHibernateCacheTimestamper(); @Override String getName(); @Override void destroy(); @Override boolean contains(Object key); @Override long getSizeInMemory(); @Override long getElementCountInMemory(); @Override long getElementCountOnDisk(); @Override Map toMap(); @Override long nextTimestamp(); @Override int getTimeout(); static final int UNKNOWN; }### Answer:
@Test public void nextTimestamp() { when(hibernateCacheTimestamper.next()).thenReturn(123L); assertThat(memcachedRegion.nextTimestamp()).isEqualTo(123L); }