Requirements for Transactional Caches

The objects you store in your transactional cache must:

Implement java.io.Serializable—This is required to store cached objects when the cache is distributed in a Terracotta cluster, and it is also required by the copy-on-read / copy-on-write mechanism used to implement isolation.
Override equals and hashcode — These must be overridden because the transactional stores rely on element value comparison. See: ElementValueComparator and the elementValueComparator configuration setting.

Additional restrictions:

Transactional mode with terracotta consistency="strong".
Caches can be dynamically changed to bulk-load mode, but any attempt to perform a transaction when this is the case causes a CacheException to be thrown.
If using "xa_strict", set synchronous writes (in ehcache.xml) to prevent potential loss of unwritten data on the client:
```
<terracotta synchronousWrites="true" />
```