Recursion in Java | Function calls by itself | Java for Beginner | Java Language.

Recursion

Java supports recursion. Recursion is the process of defining something in terms of itself. As it relates to Java programming, recursion is the attribute that allows a method to call itself. A method that calls itself is said to be recursive.

The classic example of recursion is the computation of the factorial of a number. The factorial of a number N is the product of all the whole numbers between 1 and N. For example, 3 factorial is 1 × 2 × 3, or 6. Here is how a factorial can be computed by use of a recursive method:


Program:


// A simple example of recursion.

class Factorial
{
   // this is a recursive method
   int fact(int n)
   {
      int result;
      if(n==1) return 1;
      result = fact(n-1) * n;
      return result;
   }
}
class Recursion
{
   public static void main(String args[])
   {
      Factorial f = new Factorial();
      System.out.println("Factorial of 3 is " + f.fact(3));
      System.out.println("Factorial of 4 is " + f.fact(4));
      System.out.println("Factorial of 5 is " + f.fact(5));
   }
}



The output:

Factorial of 3 is 6
Factorial of 4 is 24
Factorial of 5 is 120