JavaAlgorithms/Maths/AbsoluteValue.java

package Maths;

import java.util.Random;

public class AbsoluteValue {

  public static void main(String[] args) {
    Random random = new Random();

    /* test 1000 random numbers */
    for (int i = 1; i <= 1000; ++i) {
      int randomNumber = random.nextInt();
      assert absVal(randomNumber) == Math.abs(randomNumber);
    }
  }

  /**
   * If value is less than zero, make value positive.
   *
   * @param value a number
   * @return the absolute value of a number
   */
  public static int absVal(int value) {
    return value < 0 ? -value : value;
  }
}