Question

Often we have to use some of the methods which don’t return anything useful. If I invoke saveOrUpdate() in hibernate , I don’t know whether it has been performed successfully .
I use a implementation like this (which I think is a bit awkward) :

public int saveOrUpdateA(A a) {
        int resultFlag = 0 ;
    try {
        // obtaining session is omitted
        session.saveOrUpdate(a);
        resultFlag = 1 ;    
    } catch (Exception e) {
        e.printStackTrace();
    } 
    return resultFlag ;
}

How do you do this ? Any good idea ?

Exception should be caught in DAO layer or Service Layer ?

Answer 1

The lack of an exception is a success indicator.

If you truly want the indicator, I’d go for a boolean return.

public boolean saveOrUpdateA(A a) {
  boolean success = false;   
  try {
    // obtaining session is omitted
    session.saveOrUpdate(a);
    success = true;

  } catch (Exception e) {
    // log it and swallow exception
    // calling code has to be sure to check on success flag; 
    // otherwise it has no idea something went terribly wrong
  } 
  return success ;
}

Your application will still have to check the return status and handle it appropriately, which is not a whole lot different than handling the potential exception thrown by session.saveOrUpdate().

public void saveOrUpdateA(A a) throws Exception {

  try {
    // obtaining session is omitted
    session.saveOrUpdate(a);
  } catch (Exception e) {
    // log it and rethrow; let calling code figure how to handle
    throw e;
  } 
}