Random Number Generator in Java

package corejava;

/**An improved random number generator .Gives a set of random integers that does not exhibit

as much correlation as the method used by the Java random number generator.*/

public class RandomIntGenerator

{

 /**Constructs an object that generates random integers in a given range

@param l the lowest integer in the range

@param h the highest integer in the range */

public RandomIntGenerator(int l, int h)

{ 

low = l;

high = h;

}

/**Generates a random integer in a range of integers

@return a random integer */

public int draw()

{ 

int r = low + (int)((high - low + 1) * nextRandom());

return r;

}

/**test stub for the class*/

public static void main(String[] args)

{

 RandomIntGenerator r1 = new RandomIntGenerator(1, 10);

RandomIntGenerator r2 = new RandomIntGenerator(0, 1);

int i;

for (i = 1; i <= 100; i++)

System.out.println(r1.draw() + " " + r2.draw());

}

private static double nextRandom()

{ int pos = (int)(java.lang.Math.random() * BUFFER_SIZE);

if (pos == BUFFER_SIZE) pos = BUFFER_SIZE - 1;

double r = buffer[pos];

buffer[pos] = java.lang.Math.random();

return r;

}

private static final int BUFFER_SIZE = 101;

private static double[] buffer = new double[BUFFER_SIZE];

static { 

int i;

for (i = 0; i < BUFFER_SIZE; i++)

buffer[i] = java.lang.Math.random();

}

private int low;

private int high;

}