@Test
public void testCleanup() throws Exception {

  final DeleteOldOnAccessCache cache = new DeleteOldOnAccessCache( fileSystemCacheBackend );
  cache.setDaysToLive( 1L );
  cache.put( SOME_KEY, SOME_VALUE );
  assertNotNull( cache.get( SOME_KEY ) );
  cache.setMillisToLive( 0 );
  cache.cleanup();
  Thread.sleep( 10 );
  assertNull( cache.get( SOME_KEY ) );
}