output problems

[straggler]

I created a program to read in a file, transform the given roman numeral, double the numeral, and then output the new roman numeral.

I am not even sure yet if my Roman decrpyt and encrpytion is right because nothing is outputting into the roman.out file??

public class Roman {
 
        public void decryptEncrypt (String inputFileName, String outputFileName)
        {
            try {
                FileReader reader = new FileReader(inputFileName) ;
                Scanner in = new Scanner(reader) ;
                PrintWriter out = new PrintWriter(outputFileName) ;
 
 
                String romanout = " ";
                while (in.hasNext( ) ){
                    String roman = in.nextLine( ) ;
                    //out.print(roman);
                    for(int i = 0; i < roman.length(); i++) {
                        int num = 0;
                        char digit = ' ';
                        digit = roman.charAt(i);
                        while(digit != -1){
                            if(digit == 'I'){
                                num++;
                                if(digit == 'V'){
                                    num = num + 3;
                                }
                                else if(digit == 'X'){
                                    num = num + 8;
                                }
                            }
                            if(digit == 'V'){
                                num = num + 5;
                            }
                            if(digit == 'X'){
                                num = num + 10;
                                if(digit == 'L'){
                                    num = num + 30;
                                }
                                else if(digit == 'C'){
                                    num = num + 80;
                                }
                            }
                            if(digit == 'L'){
                                num = num + 50;
                            }
                            if(digit == 'C'){
                                num = num + 100;
                            }
 
                        }
 
            System.out.println(num);    
                            num = num * 2;
            //System.out.println(num);
 
                    while(num > 0){
                            if(num > 100){
                                num = num - 100;
                                romanout = romanout + "C";
                            }
                            if(num == 90){
                                num = num - 90;
                                romanout = romanout + "XC";
                            }
                            if(num > 50){
                                num = num - 50;
                                romanout = romanout + "L";
                            }
                            if(num == 40){
                                num = num - 40;
                                romanout = romanout + "XL";
                            }
                            if(num > 10){
                                num = num - 10;
                                romanout = romanout + "X";
                            }
                            if(num == 9){
                                num = num - 9;
                                romanout = romanout + "IX";
                            }
                            if(num > 5){
                                num = num - 5;
                                romanout = romanout + "V";
                            }
                            if(num == 4){
                                num = num - 4;
                                romanout = romanout + "IV";
                            }
                            if(num > 1){
                                num = num - 1;
                                romanout = romanout + "I";
                            }
                    }
                    out.print(roman);
                    out.print(romanout);
                    }
 
                }
                in.close( ) ;
                out.close( ) ;    
                }
            catch(IOException e)
            {
                System.out.println(e) ;
            }
        }
 
        public static void main(String [] args){    
            Roman reader = new Roman( ) ;
            reader.decryptEncrypt("roman.in", "roman.out") ;    
        }
}

[JosAH]

In the body of your while loop (starting at line #19) you never re-assign a value to variable digit so if it wasn't equal to -1 to start with that loop never terminates.

kind regards,

Jos