generate short random number in java?

Question

I want to generate a random number of type short exactly like there is a function for integer type called Random.nextInt(134116). How can I achieve it?

Answer 1

There is no Random.nextShort() method, so you could use

short s = (short) Random.nextInt(Short.MAX_VALUE + 1);

The +1 is because the method returns a number up to the number specified (exclusive). See here

This will generate numbers from 0 to Short.MAX_VALUE inclusive (negative numbers were not requested by the OP)

Answer 2

The most efficient solution which can produce all possible short values is to do either.

short s = (short) random.nextInt(1 << 16); // any short
short s = (short) random.nextInt(1 << 15); // any non-negative short

or even faster

class MyRandom extends Random {
    public short nextShort() {
        return (short) next(16); // give me just 16 bits.
    }
    public short nextNonNegativeShort() {
        return (short) next(15); // give me just 15 bits.
    }
}

short s = myRandom.nextShort();

Answer 3

Java shorts are included in the -32 768 → +32 767 interval.

why wouldn't you perform a

Random.nextInt(65536) - 32768

and cast the result into a short variable ?