How to generate a random value from an input?

I am looking for a way to generate a random value from a given input based of a seed. I'll give a code example for what I'm trying to achieve:

public class Seed {

  public double generateRandom(double input) {
    // What goes in here?
  }

}

This is how an example program could look like:

public static void main(String[] args) {
  Seed seed1 = new Seed(), seed2 = new Seed();

  System.out.println("Result of seed 1 with 69: " + seed1.generateRandom(69));
  System.out.println("Result of seed 2 with 69: " + seed2.generateRandom(69));
  System.out.println("Result of seed 1 with 420: " + seed1.generateRandom(420));
  System.out.println("Result of seed 2 with 420: " + seed2.generateRandom(420));

  System.out.println("Result of seed 1 with 69 is still: " + seed1.generateRandom(69));
  System.out.println("Result of seed 2 with 69 is still: " + seed2.generateRandom(69));
}

The output being:

Result of seed 1 with 69: 0.5
Result of seed 2 with 69: 0.65
Result of seed 1 with 420: 0.2
Result of seed 2 with 420: 0.34
Result of seed 1 with 69 is still: 0.5
Result of seed 2 with 69 is still: 0.65

What would the Seed class look like?