Java Resultset Null Pointer Exception. As mentioned in JAVAs API documents Null Pointer Exception is thrown when the null value is used instead of using a reference value. I checked the very informative post about handling NullPointer Exceptions but it didnt really work with assert either.
Its because is conn object is null. Accessing or modifying a null objects field. Java null pointer exception.
At javalangThreadrunThreadjava484 I would expect an SQLException be thrown if there was a problem.
NullPointerException is a RuntimeException. Oracle TopLink - Version 111101 and later. NullPointerException is a runtime exception so we dont need to catch it in program. So should look in constructor itself where the conn is intialised.