java - Stateful session beans vs. persistent entities -


stateful session beans illustrated implementing shopping cart. coming outside java ee, inclination handle kind of state persistent model entity: shoppingcart object products , quantities. way, state being maintained database along other state rather application server.

what technical advantages stateful session bean design on "ordinary" persistence? shopping carts in java ee-based web applications indeed written sfsbs, or in other systems more elaborate domain modeling?

there several ways implement shopping cart. main difference between sfsb , db persistence is, well, persistence :)

a stateful session bean "persist" data during session time. if user session becomes inactive (for exemple after 30 minutes of inactivity), shopping cart reset

with database persistence, shopping cart stored permenantly, if user have filled shopping cart, don't visit webshop during 6 months, , visit again, cart still filled

i think first solution used, involving non in-memory database not idea store volatile data. there lot of hard drive i/o overhead data don't need long-term persistence


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