java - Concurrency issue in JPA -


we have deployed our application in 2 application servers(tomcat server) clustering environment. request coming 2 servers @ same time concurrency issue happening means it's creating duplicate entries in database. scenario : 1. request (transaction) update data 2. request (transaction) b update data @ same time 3. 2 row added table. among 1 duplicate.

let's have methods following signature

request a

updatedata() {     //get entity manager   //start transcation tx   //persist   //commit tx }

request b

updatedata() {   //get entity manager   //start transcation tx   //persist   //commit tx }

we want prevent scenarios this. request should persist data table. solve issue. #thanks environment details: jpa 2.1 , oracle database

you should use locking in database, if using typedquery, should put in update methods:

typedquery<mytype> query = entitymanager.createquery("from mytype", mytype.class); query.setlockmode(lockmodetype.pessimistic_write);

this select update, locks entity (database rows) until lock released - so, until end of transaction.


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