Double value negative after multiplication -Java

Question

In my code i have following line.

double temp=(c12*fileSize);

• Here c12 is double and fileSizeis double
• c12 have a value 1700 and
• fileSize have a value 1944038

but after multiplication i am getting -990102696.

Can any one help me on it? Is that some size limits went wrong?

Answer 1

(int)1700 * (int)1944038 is equal to your -990102696.

Are you sure c12 and fileSize aren't integers? If they are, the multiplication occurs with integer types, integer overflow and it is being promoted to double afterwards.