How to handle JPA unique constraint violations?

Question

When a unique constraint is violated, a javax.persistence.RollbackException is thrown. But there could be multiple reasons to throw a RollbackException

Answer 1

Use e.getCause() to examine what caused the rollback.

Answer 2

compiler returns the exception SQLIntegrityConstraintViolationException, while trying to violate unique constraint.

Use the following catch block concept, to handle proper exceptions.

catch(SQLIntegrityConstraintViolationException e) 
{
  // Error message for integrity constraint violation
}
catch(Exception e)
{
 // Other error messages
}

Answer 3

You can do like this :

StringWriter writer=new StringWriter(); //remains the message from stack trace.
e.printStackTrace(new PrintWriter(writer));
String message=writer.toString(); // gets the message of full stack trace.

And then view the information of exception.

Answer 4

This might very late for you but here's how I solved it for PostGres.

catch (DataIntegrityViolationException e) {

            for (Throwable t = e.getCause(); t != null; t = t.getCause()) {

                if (PSQLException.class.equals(t.getClass())) {
                    PSQLException postgresException = (PSQLException) t;

                    // In Postgres SQLState 23505=unique_violation
                    if ("23505".equals(postgresException.getSQLState())) {
                        throw new CustomDataAlreadyExistsException("YourErrorCode", e);
                    }
                }
            }
            throw new SomeOtherException("YourErrorCode2", e);

        }

Answer 5

i think printing the stack trace will help you to know this. e.printStackTrace();

Answer 6

You have to catch javax.persistence.PersistenceException. Thrown exception is org.hibernate.exception.ConstraintViolationException.

Exception Message : org.hibernate.exception.ConstraintViolationException: Duplicate entry '893073116V-1234567' for key 'nic_account_no'