example using memcache with jpa entitymanager on JGAE?

any example on using memcache/general 开发者_StackOverflow社区cache with jpa entitymanager on JGAE? or the only way to do it is manually put/set memcache on service layer?

DataNucleus docs define adequately how to use the JDO/JPA L2 cache. http://www.datanucleus.org/products/accessplatform_1_1/jpa/cache.html in the case of GAE/J memcache the L2 cache should be "javax.cache".