To convert binary number into decimal notation

Question 74 : Write a program in Java to convert a binary number into decimal notation.

Java Program : 

class bintodec
{
 static void main(String m)
 {
     String n="";
     int i=0,d=m.length()-1;
     double a=0;
     for(d=m.length()-1;d>=0;d--)
     {
         a=a+(Integer.parseInt(n+m.charAt(d))*Math.pow(2,i));
         i++;
        }
        System.out.print("The decimal value of "+m+" is : "+a);
    }
}