Method to format long numbers in GB, MB and KB

formater.java

private String format_long(long number){
	    String formatted;
	    if (number > 1000000000) {
	       String re = "^(.*)\\d{9}$";
	       Matcher m = Pattern.compile(re).matcher(Long.toString (number));
	       if (m.find()) {
	          formatted = m.group(1) + " Gb";
	       } else {
	          formatted = "0";
	       }
	    } else if (number > 1000000) {
	       String re = "^(.*)\\d{6}$";
	       Matcher m = Pattern.compile(re).matcher(Long.toString (number));
	       if (m.find()) {
	          formatted = m.group(1) + " Mb";
	       } else {
	          formatted = "0";
	       }
	    } else if (number > 1000) {
	       String re = "^(.*)\\d{3}$";
	       Matcher m = Pattern.compile(re).matcher(Long.toString (number));
	       if (m.find()) {
	          formatted = m.group(1) + " Kb";
	       } else {
	          formatted = "0";
	       }
	    } else {
	       formatted = Long.toString (number) + " bytes";
	    }
	    return (formatted);
	
	}

formater1.java

public String readableFileSize(long size) {
	    if(size <= 0) return "0";
	    final String[] units = new String[] { "B", "KB", "MB", "GB", "TB", "PB", "EB" };
	    int digitGroups = (int) (Math.log10(size)/Math.log10(1024));
	    String result = null;
	    result = new DecimalFormat("#,##0.#").format(size/Math.pow(1024, digitGroups)) + " " + units[digitGroups];
	    return result;
	}

Output example of formater1.java

142161739776      -->      132,4 GB
1353720004608      -->      1,2 TB
80701554688      -->      75,2 GB
299842404352      -->      279,2 GB
168587952128      -->      157 GB
749740228608      -->      698,2 GB
36377198592      -->      33,9 GB
49928994816      -->      46,5 GB
46920630272      -->      43,7 GB
249913409536      -->      232,8 GB
171773526016      -->      160 GB
1722550321152      -->      1,6 TB