Basics In Java

class boolisp
{
     static int n=16;
     public static void main()
     {
         boolean k=isprime(n-1);
         if(k==true)
         System.out.println("Prime");
         else
         System.out.println("Not");
     }
     public static boolean isprime(int x)
     {
         if(x==1)
         return true;
         else
         {
             boolean k=isprime(x-1);
             if(k==true)
             {
             if(n%x==0)
             return false;
             else
             return true;
             }
             else
             return false;
          }
      }
}