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Generate Random Numbers in Android

In your apps (especially in game apps) , you may come across the need to generate random numbers. For generation of psuedo random numbers you can use random class from package java.util

First of all you can construct a random number generator using this

        mRandom = new Random(seed);

The seed should be unique for better results. You can use current time for that

                    Time t = new Time();
        t.setToNow();
        mRandom = new Random(t.toMillis(false));

Now to generate a random number from 0 to n, you can use mRandom.nextInt(n). Make sure that n is not zero.
          int rand = mRandom.nextInt(10);

The above line generates a random number between 0 to 9.

Random class also provides other functions such as nextFloat(), nextDouble, nextLong.

Comments

  1. AnonymousJanuary 21, 2013 at 4:07 AM

    Could you please show how the whole java code file looks like with this code implemented. Thanks!

    ReplyDelete
  2. Sohammmm.....!!!February 14, 2013 at 9:25 PM

    How do i make sure that these random numbers r not repeatetive ???

    ReplyDelete
    Replies
    1. UnknownFebruary 14, 2013 at 10:39 PM

      I have been using it many times in my program and I rarely see repeated numbers. When you say something like random.nextInt(100), you do get a random number. If necessary, you can modify the seed by using random.setSeed(long), where you can use the current time as the seed value.

      Delete

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