I was reading an article about Hibernate Caching and one thing jumps to my notice:

"One thing you should know is that the Hibernate cache does not store object instances. Instead, it stores objects in their "dehydrated" form (to use Hibernate terminology), that is, as a set of property values."

My question is why Hibernate cache does not store object instances. Are there any drawbacks with storing obejct instances?

Thanks

Anyone please?

Thanks

#1: if we returned the same object instance to multiple concurrent sessions they would no longer be isolated and you would get hard to find consistency issues

#2: Since we can't return the same object instances to multiple concurrent sessions why should we waste cpu cycles on creating objects we don't need ?

#3 Read Hibernate In Action which explains this (and much more)

for a read-only cache would not it make more sense to have the same object instance to mulitple concurrent sessions? why would i want isolation in this case?

Thanks

For consistency and to shield you from users which might have invoked operations on the cached object that mutates it...

If you know you can handle that then implement Interceptor.getEntity() to keep a cache of precreated objects.