Building a library of mathematical functions.

Q:

Implement a class method methods double abs(double) and two overloaded methods double max(double, double) and double max(double, double, double) in a class Math living in a package of your choice:

package de.hdm_stuttgart.de.sd1.math;

/**
 * Some class methods.
 */
public class Math {

  /**
   * Return the absolute value of a given argument
   * @param value The argument to be considered
   * @return the argument's absolute (positive) value.
   */
  public static double abs(double value) {
    ... return ??;
  }

  /**
   * The maximum of two arguments
   * @param a First argument
   * @param b Second argument
   * @return The maximum of a and b
   */
  public static double max(double a, double b) {
    ... return ??;
  }

  /**
   * The maximum of three arguments
   *
   * @param a First argument
   * @param b Second argument
   * @param c Third argument
   * @return The maximum of a, b and c
   */
  public static double max(double a, double b, double c) {
    ... return ??;
  }
}

Provide at at least 8 unit tests.