Best practice for getting datatype size(sizeof) in Java

Question

I want store a list of doubles and ints to a ByteBuffer, which asks for a size to allocate. I'd like to write something like C's syntax

int size=numDouble*sizeof(double)+numInt*sizeof(int); 

But there is no sizeof in Java. What is the best practice to calculate the size in byte? Should I hardcode it?

Answer 1

See @Frank Kusters' answer, below!

(My original answer here was for Java versions < 8.)

Answer 2

Since Java 8, all wrapper classes of primitive types (except Boolean) have a BYTES field. So in your case:

int size = numDouble * Double.BYTES + numInt * Integer.BYTES; 

Documentation: http://docs.oracle.com/javase/8/docs/api/java/lang/Integer.html