how to generate unique numbers less than 8 characters long.
- by loudiyimo
hi
I want to generate unique id's everytime i call methode generateCustumerId(). The generated id must be 8 characters long or less than 8 characters.
This requirement is necessary because I need to store it in a data file and schema is determined to be 8 characters long for this id.
Option 1 works fine. Instead of option 1, I want to use UUID. The problem is that UUID generates an id which has to many characters. Does someone know how to generate a unique id which is less then 99999999?
option 1
import java.util.HashSet;
import java.util.Random;
import java.util.Set;
public class CustomerIdGenerator {
private static Set<String> customerIds = new HashSet<String>();
private static Random random = new Random();
// XXX: replace with java.util.UUID
public static String generateCustumerId() {
String customerId = null;
while (customerId == null || customerIds.contains(customerId)) {
customerId = String.valueOf(random.nextInt(89999999) + 10000000);
}
customerIds.add(customerId);
return customerId;
}
}
option2 generates an unique id which is too long
public static String generateCustumerId() {
String ownerId = UUID.randomUUID().toString();
System.out.println("ownerId " + ownerId);
return ownerId
}
