Java String Leading Character addLeadingZeros(Object number, int places)

Description

add Leading Zeros

License

Open Source License

Parameter

Parameter	Description
number	object representing a number.
places	to the left of decimal to fill with zeros.

Exception

Parameter	Description
NCSAException	if number is not a valid number.

Return

String representation of number with leading zeros added.

Declaration

public static String addLeadingZeros(Object number, int places) throws IllegalArgumentException 

Method Source Code

//package com.java2s;

public class Main {
    /**//from  ww w . j a v a2s.co  m
     * @param number
     *            object representing a number.
     * @param places
     *            to the left of decimal to fill with zeros.
     * @return String representation of number with leading zeros added.
     * @throws NCSAException
     *             if number is not a valid number.
     */
    public static String addLeadingZeros(Object number, int places) throws IllegalArgumentException {
        if (number == null)
            return null;
        if (number instanceof String)
            try {
                Double.valueOf((String) number);
            } catch (Throwable t) {
                throw new IllegalArgumentException(
                        "addLeadingZeros, problem with string value " + number + ": " + t.getCause());
            }
        else if (!(number instanceof Number))
            throw new IllegalArgumentException(number + " is not a Number");

        StringBuffer suffix = new StringBuffer(0);

        long l = 0;
        int start = 0;
        int end = -1;
        int zeros = places;

        suffix.append(number);

        if (suffix.toString().equals("null"))
            throw new IllegalArgumentException("no number string to modify");

        if (suffix.charAt(0) == '-')
            start = 1;
        else
            start = 0;

        while (start < suffix.length() && suffix.charAt(start) == '0')
            suffix.deleteCharAt(start);

        end = suffix.indexOf(".");
        if (end < 0)
            end = suffix.length();

        String intPart = suffix.substring(start, end);

        if (intPart == null || intPart.length() < 1) {
            l = 0;
            if (zeros > 0 || end == suffix.length())
                suffix.insert(start, "0");
        } else
            l = new Long(suffix.substring(start, end)).longValue();

        do {
            zeros--;
            l /= 10;
        } while (l > 0);

        for (int i = 0; i < zeros; i++)
            suffix.insert(start, "0");

        return suffix.toString();
    }
}

Related

1. addLeadingUnixSlash(String fileName)
2. addLeadingZero(byte[] value)
3. addLeadingZero(final int value)
4. addLeadingZero(String aString, int aAmountOfZeros)
5. addLeadingZeroesTo16BitBinaryString(String binaryValue)
6. addLeadingZeros(String deweyCallNum)
7. addLeadingZeros(String number, int maxDigits)
8. addLeadingZeros(String s, int nZeros)
9. addLeadingZeros(String str)