@Override
 public boolean putFromLoad(
     Object key, Object value, long txTimestamp, Object version, boolean minimalPutOverride)
     throws CacheException {
   if (minimalPutOverride && cache.get(key) != null) {
     return false;
   }
   // OptimisticCache? versioning?
   cache.put(key, value);
   return true;
 }
 @Override
 public Object get(Object key, long txTimestamp) throws CacheException {
   return cache.get(key);
 }
 @Override
 public boolean update(Object key, Object value) throws CacheException {
   cache.put(key, value);
   return true;
 }