java.lang.ClassCastException: java.math.BigInteger cannot be cast to java.lang.Long

Question

I want to return number of rows using native sql. But console says me java.math.BigInteger cannot be cast to java.lang.Long. What\'s wrong? This is my method:

Answer 1

Use BigInteger#longValue() method, instead of casting it to Long:

return firstResult.get(0).longValue();

Seems like firstResult.get(0) returns an Object. One option is to typecast to BigInteger:

return ((BigInteger)firstResult.get(0)).longValue();

But don't do this. Instead use the way provided by Nambari in comments. I'm no user of Hibernate, so I can't provide Hibernate specific solution.