java - Should annotation based JPA Entity Manager be closed? -


i have used annotation using entity manager instead of using entitymanagerfactory.

@persistencecontext entitymanager entitymanager;

i searched lot regd closing of entitymanager. in places entitymanager being used 

entitymanager em = emf.get().createentitymanager();

and im not sure how closing varies annotation based. use use normal jdbc connection? eg: 

connection conn=databaseconnection.getconnection(); preparedstatement stmt; resultset result; stmt=conn.preparestatement("select * table id = ?  "); stmt.setstring(1,id); result=stmt.executequery(); conn.close();

so, need add begin tran entitymanager, commit , close each method use? or annotation take care of all?

public class someclass{     public somemethod1(){      //use entitymanager - need close each method?     }     public somemethod2(){      //use entitymanager     } }

or getting entirely wrong? please advice.


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