How to generate 12 digit sequence number in java

Question

I want to generate 12 digit mobile number. It's start with 910. Ex: 910000000001, 910000000002, 910000000003.

It is possible in java?

Answer 1

It depends on what you want to do.

If you want to just get the nextNumber: I would suggest AtomicLong. https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/atomic/AtomicLong.html#AtomicLong-long-

class GetNextNumber {
    private static AtomicLong numberGenerator = new AtomicLong(910000000000L);

    public static long getNext() {
        return numberGenerator.getAndIncrement();
    }
}

If you need random numbers (with possible duplicated, you can use the ThreadLocalRandom as suggested by Ravi.

Answer 2

It seems like you want to generate all numbers in sequence from 910000000000 to 910999999999?

You could do something like this.

    long counter = 910000000000L;
    while(counter <= 910999999999L) // You can change this constant if you want the loop to break sooner
    {
        //Print, add to list, whatever
        counter++;
    }

Edit: It needs to be long

Answer 3

如果您正在寻找以 9 开​​头的随机数 12 位数字，您可以使用ThreadLocalRandom

System.out.println( ThreadLocalRandom.current().nextLong( 910000000001L, 910999999999L ) );