program for display hexa to binary or decimal in java

class hexa_2_decinbinary
{
public static void meth(String s)
{
int g,num=0,a=0;
   
  
int l=s.length();
for(int i=l-1;i>=0;i--)
{
char c=s.charAt(i);
if(c>=65 && c<=70)
{c-=55;
 g=c;

num=num+(g*((int)Math.pow(16,a)));
    }
    else
    {
        c-=48;
         g=c;
        
         num=num+(g*((int)Math.pow(16,a)));
        }
        a++;
    }
  
    int ar[]=new int [15];
    int c=-1;int temp=num,gh=num;
   while(num>0)
   {
       c=c+1;
      
     int  r=num%2;
    ar[c]=r;
    num=num/2;
}

     System.out.println("the decimal value of the haxadecimal number is "+gh);
    for(int i=c;i>=0;i--)
    {System.out.print(ar[i]);
    }
}
    }