How can we generate automatic id

Question

Hi,
I want a automatic id like
String str="java"+System.currentTimeMillis();
if any other way we will generate automatic id.Please reply me

Answer 1

Hai
If u want to generate a random ID then u can use the Java Random class But we cannot make sure that the generated ID will be unique. But most probably it will not repeat. This problem can be avoided by setting primary key for the ID in the DB. So if the ID exists it will throw an exception , then u can generate the next ID.
Random random = new Random();
          for (int i = 0; i < 100; i++) {
               double d = random.nextDouble();
               long l = random.nextLong();
               l = Math.abs(l);
               System.out.println("l : "+ l + "  d : " + d);
          }