I am trying to test a java.sql.SQLException handler which unwraps the exceptions like below. However I'm not sure how I would throw this exception in a test.

(-> e
           (.getNextException)
           (.getMessage)
           (.startsWith "ERROR: duplicate key value"))

(throw (SQLException. "ERROR: duplicate key value"))

@hackeryarn use setNextException(): http://docs.oracle.com/javase/8/docs/api/java/sql/SQLException.html#setNextException-java.sql.SQLException-

Ah thank you @seancorfield, looks like a BatchUpdateException is actually thrown before the duplicate key exception and that's why the .getNextException is needed.

That helped me understand how the transaction is run a bit better too.