package trianglecalculation;

import java.text.*;
import java.io.*;
import java.util.*;
/* This class uses ArrayList of triangular objects to
   calculate their total area and perimeter.  
*/  
public class Main
{

   /* this method is used to read in the object sides,
   it needs additional validation  */
   public static double input (BufferedReader r, String prompt) throws
IOException
   {
       double side=0.0;
   
       // handle the exceptions
       try {
           System.out.print( "Please enter " + prompt);
           String myString = r.readLine();
           side = Double.parseDouble(myString);
           }

       catch (NumberFormatException nfe)
               {
                   System.out.println("Please enter a number!\n" + nfe);
               }
       return side;
   }       // end of input()

public static double main(String[] args) throws IOException  // Array list
will be used instead of array?!
   {
       ArrayList aList = new ArrayList();    // Created with default size
(10).
       Triangle ob = new Triangle(); // will be used as work object

       int choice = 0;     // for the user choice
       double side1, side2, side3;
       boolean exceptThrown = false; // if exception is thrown
       InputStreamReader isr = new InputStreamReader(System.in);
       BufferedReader br = new BufferedReader(isr);

       do  {
               try {
                       System.out.print(" Please choose a triangular
object to add: ");
                       System.out.println( " 1: General; 2: Equilateral;
3: Right; 0: None ");
                       String myString = br.readLine();   //reads a line
(string) from the buffer br
                       //Parses the string argument
                       choice = Integer.parseInt(myString);
                   }

               catch (NumberFormatException nfe)
                   {
                       exceptThrown = true;
                       System.out.println( "Please enter a number!\n" +
nfe);
                   }

               switch (choice)
               {
                 case 1: side1 = input(br, "side1: " );
                     side2 = input (br, "side2: " );
                     side3 = input (br, "side3: " );      
                     Triangle tri = new Triangle(side1, side2, side3);
                     aList.add((Object) tri); //add to the list
                     break;

                 case 2: side1 = input(br, "side: ");
                       EquilateralTriangle equi = new
EquilateralTriangle(side1);
                       aList.add((Object) equi); //add to the list
                       break;
               
                 case 3: side1 = input(br, "side1: ");
                     side2 = input (br, "side2: ");      
                     RightTriangle rig = new RightTriangle(side1,
side2);
                     aList.add((Object) rig); //add to the list
                     break;

                 case 0: break;
                   default: System.out.println( "\n Wrong choice!" );
                   exceptThrown = true;  
               }
   
           } while (choice != 0 && !exceptThrown);  //repeat the input

       if (!exceptThrown)   // will skip, if an exception was thrown
           {
               double totalA, totalP; // for the total area and
perimeter
               System.out.println("\nObjects \t\t\t area \t\t
perimeter:");
               // To accumulate the total area and perimeter
               totalA = totalP =0.0;
               /* In this loop each object from the array list will be
extracted and its name, area, and perimeter printed out. */

               for(int i = 0; i < aList.size(); i++)
                   {
                       ob = (Triangle)aList.get(i); //casting to
Triangle
                       System.out.print (ob.displayName());
                       System.out.print ( "\t--> " + ob.area());
                       System.out.println ( " \t: " + ob.perimeter());
                       totalA +=  ob.area();
                       totalP +=  ob.perimeter();
                   }

               /*  if you would like to specify the number of fraction
digits,
                 use the NumberFormat abstract class.      */  
                 NumberFormat nf;  // this is not an object
                //Returns a general-purpose number format for the current
default locale      
                 nf = NumberFormat.getNumberInstance();
                 nf.setMaximumFractionDigits(3); // to specify the number
of fraction digits

                String areaTotal = nf.format(totalA); // convert to
String
                String perimTotal = nf.format(totalP);
                System.out.print("\nTotal area and perimeter are:");
                System.out.println("\t\t" +areaTotal+ " :  
"+perimTotal);

               
           } // end if

       
    } // end main - here it says there is a missing return statement
} // end class

I don't need there to be an else, nor do I need an "=" within the if, so
any ideas what I can do to fix this?