Java Program to print the area of an Triangle

import java.io.*;
import java.util.*;
public class Triangle{
    Scanner scan=new Scanner(System.in);
    double area;
    float s, s1, s2, s3;
    public void input()throws IOException{
        System.out.println("Enter three sides of the triangle: ");
        s1=scan.nextFloat();
        s2=scan.nextFloat();
        s3=scan.nextFloat();
    }

    public void compute(){
        s=(s1+s2+s3)/2;
        area=Math.sqrt(s*(s1-s)*(s2-s)*(s3-2));
    }

    public void display(){
        System.out.println("Three sides are: \n1. "+s1+"\n2. "+s2+"\n3. "+s3);
        System.out.println("Area: "+area);
    }

    public static void main(String[] args)throws IOException{
        Triangle obj=new Triangle();
        obj.input();
        obj.compute();
        obj.display();
    }
}