Recursion: another example : Recursive Method « Class Definition « Java Tutorial

1. Java Tutorial
2. Class Definition
3. Recursive Method

public class MainClass {
  public static void main(String[] args) {
    double x = 5.0;
    System.out.println(x + " to the power 4 is " + power(x, 4));
    System.out.println("7.5 to the power 5 is " + power(7.5, 5));
    System.out.println("7.5 to the power 0 is " + power(7.5, 0));
    System.out.println("10 to the power -2 is " + power(10, -2));
  }

  // Raise x to the power n
  static double power(double x, int n) {
    if (n > 1)
      return x * power(x, n - 1); // Recursive call
    else if (n < 0)
      return 1.0 / power(x, -n); // Negative power of x
    else
      return x;
  }
}

5.0 to the power 4 is 625.0
7.5 to the power 5 is 23730.46875
7.5 to the power 0 is 7.5
10 to the power -2 is 0.01