StackOverflowError caused by conversion program

Question

Hello all,
I'm a bit new to Java, so please bear with me if the answer to my problem is an obvious one.
I am trying to write a program to convert numbers (floating and negative, too) from the given base to base 10. As this is part of a larger project, what i have already written will no doubt appear as overkill, but the code in question can be found at http://rafb.net/paste/results/YDpaXH25.html (the relevant section is bounded by 5 lines of asterisk comments on top and bottom). In any case, though the current code has no syntax errors, a runtime error does occur when i try to call it like so;
// java code
public class BasemathInterface {
public static void main(String[] args) {
Basemath a = new Basemath();
a.convertBase(10, 23.4, false);
//end java code
a StackOverflowError:
Exception in thread "main" java.lang.StackOverflowError
Press any key to continue . . .
I suspect this has something to do with line 88, where the second "half" of floating-point numbers are handled, since I've heard StackOverflowErrors are often caused by infinite loops, though i'm not sure how the current code would set up such a loop. Any help would be appreciated.
Thanks in advance.

Answer 1

Hello again . . . I changed the method a bit so that a StackOverflowError doesn't happen, but unfortunately that's because two "possible loss of precision error"s (num1 = convertBase(base, num1, false); num2 = convertBase(base, num2, true)) prevent the program from compiling . . . any ideas on why these happen and/or how to fix it would be appreciated.
     public double convertBase(int base, double num, boolean lessone) {
          int negflag = 0;
          int x;
          boolean conflag;
          String convert = "";
          if (contains(Double.toString(num), ".")) {
               int dot = index(Double.toString(num), ".");
               int num1 = Integer.parseInt(Double.toString(num).substring(0, dot));
               int num2 = Integer.parseInt(Double.toString(num).substring(dot+1));
               num1 = convertBase(base, num1, false);
               num2 = convertBase(base, num2, true);
               dot = index(Double.toString(num), ".");
               num2 = Integer.parseInt(Double.toString(num).substring(dot));
               num = Double.parseDouble(Double.toString(num1) + "." + Double.toString(num2));
          else {
               String[] number =  new String[Double.toString(num).length()];
               int[] inumber = new int[Double.toString(num).length()];
               for (int i = 0; i < number.length; i++)
                    number[i] = Double.toString(num).substring(i-1, i);
               if (lessone == false){
                    x = 0;
               else {
                    x = -1;
                    reverse(number);
               reverse(number);
               for (int i = 0; i < number.length; i++) {
                    if (overten.containsKey(number)) {
                         conflag = true;
                         convert = number[i];
                         Integer ovr10 = (Integer)overten.get(number[i]);
                         number[i] = Integer.toString(ovr10.intValue());
                    else conflag = false;
                    if (number[i].equals("-")) {
                         negflag += 1;
                         remove(number, i);
                         continue;
                    else ;
                    if (Integer.parseInt(number[i]) < base) {
                         number[i] = Double.toString(Integer.parseInt(number[i]) * Math.pow(base, x));
                         if (!lessone)
                              x += 1;
                         else x -= 1;
                    else {
                         if (conflag) {
                              System.out.println("Numbers of Base " + base + " Cannot Have '" + convert + "' In Them.");
                         else System.out.println("Numbers of Base " + base + " Cannot Have " + number[i] + "'s In Them.");
               for (int i = 0; i < number.length; i++) {
                    if (!lessone)
                         inumber[i] = Integer.parseInt(number[i]);
                    //else inumber[i] = Double.parseDouble(number[i]);
               if (negflag % 2 != 0)
                    return -1 * sum(inumber);
               return sum(inumber);
          return 1;