java - How do i properly cache common objects / entities when using JPA? -

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i have web app needs load rows tables in database objects re-used in various places within application.

for instance, might retrieve list of locations change infrequently, want store in memory quicker access later on.

next, in future request, want associate 1 of these entities entity in database; however, jpa throws errors when attempting save, because cached entity detached.

how reattach cached entity can include in current transaction?

i'm using apache openjpa implementation.

calling entitymanager.merge() re-attach detached object.

have @ informative page


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