java. lang.ClassCastException：java. Lang. integer cannot be cast to Java lang.Double

I'm running into a problem compiling this code, which gives me an error, Java Lang. integer cannot be cast to Java lang.Double. If someone helped me modify this code, I would be very happy

double x;

 public Double getmethod() {

     HashMap hashmap= new HashMap();

     hashmap = SumCal();

     List  listabc = (List) hashmap.get("abclist");
     int total=(Integer) hashmap.get("all_total");
     x = (Double) listabc.get(0)*100/total;
     return x;
    }

Solution

You can do this, but I'll suggest you go to generics

x = ((Integer) listabc.get(0) * 100 / total);

If you have used the following generics, no projection is required

List<Integer> listabc 
HashMap<String,Integer> hashmap 
x = listabc.get(0) * 100 / total;

In that case, you don't need any casting One of the reasons for introducing wrapper classes such as integer and double is to avoid coercion