multithreading - Java Multithreaded Transactional service layer -


i have task in have implement transactional service layer manages multiple daos (those daos have crud operations). in order insert database have use multiple daos, need start transaction.

i implemented daomanager class implements singleton pattern. class has methods getnewsdao() return instance of dao. can daomanager , dao classes have single instance per program.

i implemented connectionmanager class has 2 fields - connection pool (used retrieving connection) , connection field.

basically, when call service layer method flow like:

  • get connection connection pool , set connection field inside connection manager
  • call dao methods , pass them connection field connectionmanager method parameter

every service class has daomanager field - singleton , connectionmanager field - connectionmanager not singleton. has instance per service class instance.

the problem comes when multiple threads use service classes. a transaction made single thread have make sure same connection not shared among threads.

should move daomanager , connectionmanager in thread local , make connectionmanager singleton? single instance of daomanager , conenctionmanager per thread , change passing connection method in dao setting in instance field of dao?

or design practice?


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