How to get a 38 character length number from database /NUMBER(38, 0)/?

Question

I need to store in a database number that is 38 character long, that works fine for me but when I am reading from database using JDBC driver my number I get not that I have putted into database i. e.:
inserted to database: 34028236692093846346337460743176821145
result of reading from database via JDBC driver: 34028236692093800000000000000000000000 (return type is BigDecimal... :/ and I would expect BigInteger...)
my db version is Oracle 10.2.0.4.0 Enterprise Edition
and JDBC driver version is 10.2.0.4.0

Answer 1

no, num.doubleValue() is not exact enough (can lead to different numbers after the decimal point). the only way i have found so far to convert exactly is to use the String constructor of BigDecimal.
the starnge thing is, that the same value as a fixed string works, but not the string value:
    public static BigDecimal toBigDecimal(String string, String pattern) {
        BigDecimal result = null;
        if (string != null) {
            java.text.DecimalFormat df = new java.text.DecimalFormat(pattern);
            Number num = df.parse(string, new java.text.ParsePosition(0));
            if (num != null) {
                try {
                    string = string.replace(',', '.');
                    System.out.println("1: "+new BigDecimal("12.34"));
                    System.out.println("2: "+new BigDecimal(string)); //thorws NumberFormatException, even though string has the value "12.34" (checked with debugger)
                    result = new BigDecimal(string);
                } catch (NumberFormatException nfe) {
                    System.err.println("toBigDecimal():"+ nfe);
        return result;
    }//toBigDecimal()output:
1: 12.34
toBigDecimal():java.lang.NumberFormatException: 1234
where is the decimal point? the debugger shows that 'string' has the value "12.34" (with decimal point)????