Volatile or synchronized for primitive type?

Question

In Java, assignment is atomic if the size of the variable is less than or equal to 32 bits but is not if more than 32 bits.

What (volatile/synchronized) would be more ef

Answer 1

According to the oracle documentation, you can use volatile to refer to Double object:

volatile Double x = y;

"Writes to and reads of references are always atomic, regardless of whether they are implemented as 32-bit or 64-bit values."