Format and unformat numbers.

NumberUtils.java

import java.text.DecimalFormat;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class NumberUtils {

    private static final Pattern FORMAT_PATTERN = Pattern.compile("^\\d{1,3}([a-zA-Z]+|\\.\\d{1,2}[\\D]+$)");
    private static final Pattern NUMBER_PATTERN = Pattern.compile("((^\\d{1,3})([.][\\d+]{1,2})?)(\\D+$)?");

    private static final DecimalFormat DECIMAL_FORMAT = new DecimalFormat("#,###.##");
    private static final List<String> FORMATS = Arrays.asList("","K","M","B","T","Q","QQ","S","SS","OC","N","D","UN","DD","TR","QT","QN");

    public static String format(double number) {
        int base = (int) Math.log10(number);
        int index = base / 3;

        if(index < 0) {
            index = 0;
        }

        number = (number / Math.pow(10, index * 3));

        String symbol = index < FORMATS.size() ? FORMATS.get(index) : "";
        return DECIMAL_FORMAT.format(number) + symbol;
    }

    public static boolean isFormatted(String string) {
        return FORMAT_PATTERN.matcher(string).matches();
    }

    public static double unformat(String string) {
        if(!isFormatted(string)) {
            throw new IllegalArgumentException("the value " + string + " is not in a valid format");
        }

        try {
            Matcher matcher = NUMBER_PATTERN.matcher(string);
            if(matcher.find()) {
                String value = matcher.group(1);
                String format = matcher.group(4);

                double number = Double.parseDouble(value);
                int index = FORMATS.contains(format) ? FORMATS.indexOf(format) : 0;

                return number * Math.pow(1000, index);
            }

        } catch (Exception e) {
            e.printStackTrace();
        }

        return 0;
    }
}