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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();
        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.


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

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

    1. 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.


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